420-71 Million Years Ago
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420Mil BC - 375Mil BC The climax
of the closure of the Caledonian and Appalacian geosynclines in
Siluro-Devonian times is known as the Caledonian orogeny. At this
time the western and central parts of Laurasia were brought together
in a clinch that lasted until late in the Jurassic period when the
Atlantic rift began. The Ural sea remained open.
417Mil BC - 354Mil BC The Devonian Period
The Caledonian mountains formed in the early half
of this period.
The heyday of the brachiopods was the Devonian
period when they occupied the sea floor in amazing numbers.
In Devonian time the early simple growths of
plants were joined by the first fern-like plants.
By the early Devonian the Appalacian ocean had
been completely squeezed out of existence in the north.
Floating or swimming creatures, such as
graptolites, were plentiful in the Cambrian, Ordovician and Silurian
seas, but together with other shallow-water planktonic forms of life
they became extinct in the Devonian.
In the Devonian there was a veritable explosion
of the scaled and finny. Perhaps the rivers and lakes of the new
Devonian continents became accessible at a time when the fish had
reached a point in evolution where they could adopt to non-salty
Earth movements throughout early Paleozoic times
occurred frequently in Europe and North America and reached a climax
in the Devonian. Known as the Caledonian orogeny, this climax was
accompanied by the intrusion of granites and widespread alteration
of the old geosynclinal sediments. Resting upon the eroded stumps of
the Caledonian rocks are the Old Red Sandstone formations. Boulder
and pebble beds, sands and clays derived from the underlying
formations, these beds contain the remains of strange and armored
The land area that arose in the North Atlantic
region has been called the North Atlantis or the Old Red Sandstone
continent. It spanned what is now the North Atlantic but perhaps the
lines along which it would break in the Mesozoic were already
A continuation of the Caledonian orogeny along
the maritime coast of Canada is called the Acadian earth movement.
Nearly all the continent of N. America was
covered by transgressive seas in the Ordovician and the Devonian,
and again in the Cretaceous.
In eastern Australia a large mobile best lasted
until the Permian period. This, the Tasmanian geosyncline,
experienced many disturbances and volcanic episodes alternating with
415Mil BC The lighthouse at Peggy's Cove in
Halifax, Canada, stands on granite boulders of this age.
(SFEC, 11/28/99, p.T8)
415Mil BC - 360Mil BC In Devonian strata from
Greenland in 1948 there was found the fossil, Ichthyostega, the
earliest and most primitive of known fossil amphibian.
(E&IH, 1973, p.125)
412Mil BC - 354Mil BC The Devonian. Placoderms,
fishes with armored heads and trunks were abundant during the
Devonian but died out towards the end. They moved their tails from
side to side and included Dunkleosteus.
(NH, 6/96, p.24)
400Mil BC Scientists in 2004 reported that an
insect fossil named Rhyniognatha, found in Scotland in the 1920s,
dated to this time and speculated that it had wings and could fly.
(SFC, 2/12/04, p.A2)
400Mil BC Scientists in 2006 reported that an
armored fish from this time called Dunkleosteus terreli grew up to
30 feet, weighed as much as 4 tons, and used its powerful toothless
jaws to tear food apart.
(SFC, 11/29/06, p.A6)
400Mil BC Fossil remains of coelacanth fish have
been identified in deposits dating back nearly 400 million years.
The fish has a rostral organ in its skull, a feature similar to one
that sharks use to detect the weak electric fields given off by
their prey. Living specimens in 1938 were caught off the coast of
East Africa and in 1998 were caught in Indonesian waters. The
females were found to bear live young following internal
(NG, 6/1988, p.833-834)(SFC, 9/24/98, p.A2)
400Mil BC The evolutionary path of sharks and
humans parted about this time.
(NH, 9/96, p.40)
400Mil BC Subduction of the Pacific plate under
the American continent formed the Kalmiopsis wilderness in
(SFEC, 6/20/99, p.T8)
400Mil BC Astronomers in 2002 identified a binary
black hole from this time that resulted from the collision of 2
galaxies and blended to form NGC6240.
(SFC, 11/25/02, p.A6)
400Mil BC - 300Mil BC Mid
Paleozoic: Laurasia formed about this time
consisting of North America, Greenland, the Baltics, France and
400Mil BC - 300Mil BC Pan-African orogenies. This
period of transformation almost doubled the stable crust in Africa.
The previously separate cratons and the newly heated and compressed
mountain root regions between them were fused into a single shield.
Apart from small areas in the north-west, south-east and the Cape
region, the continent had achieved the outline we know today.
397Mil BC Four-legged creatures were mucking
around a muddy basin in what is now Poland about this time. In 2010
scientists reported the discovery of their the fossilized footprints
in the Holy Cross Mountains in southeastern Poland.
390Mil BC In 2007 British scientists reported a
fossilized claw, part of an ancient sea scorpion, that was 8-feet
long, making the entire creature the biggest bug ever. The fossil
was from a Jaekelopterus Rhenaniae, a kind of scorpion that lived
only in Germany for about 10 million years.
385Mil BC A fish species later called
Panderichthys lived about this time.
(Econ, 4/8/06, p.79)
385Mil BC In the Middle Devonian the sea slowly made its way
back into the continental interior of North America. After this slow
start the flooding began to quicken so that in middle Devonian time
it reached across the interior around the Canadian Shield. Only the
Transcontinental Arch, the Ozark Dome and other minor regions were
not covered. To the west the shallow waters spread over an area that
began to warp gently into one of the most remarkable of shelf
basins, the Williston Basin. The deposits of the Williston Sea gave
rise to oil and gas in huge quantities that were preserved in the
porous reef rocks and limestones close at hand.
Real forests of lush plants with well-developed
leaves and fronds had taken root by the Middle Devonian, and at the
end of the period were reaching 7 meters or more in height, towering
over a thick underbrush of ferns, mosses, liverworts and other
385Mil BC Microbranchius dicki, a placoderm fish,
lived about this time. Placoderms were among the first jawed
vertebrates to evolve and are ancestral to humans. Scientists
studying fossils of M. Dicki in 2014 said their physical structure
suggested the fish engaged in copulation.
(Econ, 10/25/14, p.83)
383Mil BC In 2004 paleontologists found fossils of
a primitive fish, named Tiktaalik roseae, on Ellesmere Island in
Canada’s Nunavut territory that dated to about this time. The
fossils showed evidence of ribs, neck, rudimentary ear bones and
(SFC, 4/6/06, p.A1)(Econ, 4/8/06, p.79)
380Mil BC Reconstruction from fossils of North
American Devonian reef formations of life on a coral reef shows:
sponges, corals, lampshells, snails, trilobites, sea lilies,
octopus-like cephalopods, together with fronds of seaweed and moss
380Mil BC Creatures with four limbs began to
(NYT, 6/7/96, p.B1)
380Mil BC In 2008 scientists traced the origin of
fingers and toes to fish-like creatures that roamed the seas about
this time. In 1839 Swiss scientist Louis Agassiz described a fossil
fish that had been found in Permian marl slate near Durham, northern
England. He named it coelacanthus. Over the decades similar fossils
were found dating from around 380 million to 70 million years ago.
(AFP, 9/21/08)(Econ, 12/14/13, IL p.10)
380Mil BC The oldest known insect fossils are tiny
imprints of wingless insects found in sandstone rocks of the
mid-Devonian period dated to this time.
380Mil BC In 2009 Scientists from Australia and
Britain studying 380 million-year-old fossils of the armored
placoderm fish, or Incisoscutum richiei, said embryos in the fish
indicated that sex as we know it, fertilization of eggs while they
are still inside a female, took place as much as 30 million years
earlier than previously thought. They originally thought the fish
laid their eggs before fertilization.
375Mil BC Coralville Lake in Iowa, USA, overflows
a spillway in 1993AD and bares fossils beneath the soil downstream
of creatures of the Devonian period. The fossils indicate that the
area was under water during this period.
(NG, Geographica, Jan, 94)
375Mil BC In 2006 scientists reported the
discovery of a predator fossil fish dating to this time in on
Canada’s Ellesmere Island in the High Arctic. It was later named
Tiktaalik roseae and further analysis found it to have developed a
mobile neck, an important development for living on land. The fish
displayed bones at the ends of its fins suggestive of developing
fingers and toes.
(SFC, 10/16/08, p.A10)(SFC, 5/12/09, p.A8)
370Mil BC Devonian corals are now known to have
secreted skeletons of calcium carbonate, calcite, in a very regular
way., adding tiny rings of it to the top of their skeletal cup as
they grew. The daily increments of regular measure repeat in units
of 400 rather than 365. At that time the day would have bee 21.9
There were protozoans by the
millions. Only when they, too, developed a hard case of calcium
carbonate late in the Devonian period did they bequeath something of
a fossil record. The blankets of sediment from these tiny animals
accumulated with the corals and crinoids to give us the limestone of
370Mil BC Similar corals found in both Morocco and
New York indicate that the two areas were neighbors at this time.
(Nat. Hist., 4/96, p.52)
370Mil BC - 290Mil BC The Variscan or Hercynian
orogeny from Alabama to Newfoundland in eastern North America,
Britain, mainland Europe, and coastal north-west Africa. This was
another geosyncline-like belt.
365Mil BC Acanthostega, the oldest known
tetrapod, was later regarded as an early amphibian. It used its
limbs to paddle along the bottom of shallow bays and estuaries. It
was about 2-feet long and its limbs ended with 8 delicate fingers.
(NH, 6/96, p.39)(Econ, 4/8/06, p.79)
365Mil BC In 2008 scientists unearthed a skull,
dating to about this time, of the most primitive four-legged
creature in Earth's history, which should help them better
understand the evolution of fish to advanced animals that walk on
land. The fossil skull, shoulders and part of the pelvis of the
water-dweller, Ventastega curonica, were found in Latvia.
365Mil BC - 357Mil BC A 2nd known mass extinction
occurred near the end of the Devonian.
(SFEC, 8/22/99, Par p.12)(SFC, 3/19/04, p.A5)
LOWER CARBONIFEROUS: MISSISSIPPIAN PERIOD 360 - 320 Million Years
(E&IH, 1973, p.42)
360Mil BC Towards the end of the Devonian period
the seas drew back from the Gondwana super-continent.
360Mil BC By late Devonian time some bony fish not
only undoubtedly had lungs, but also had stumpy or lobed fins, the
antecedents of legs. The 2-foot long ichthyostega from eastern
Greenland was among the 1st fish to move on land. Bony fish were
restricted to fresh water until about 55 million BC
(DD-EVTT, p.254)(SFC, 9/12/05, p.A4)(Econ,
359Mil BC - 345Mil BC In 2005 it was reported that
tracks of 4-legged terrestrial animals dated to this period were
found at Nova Scotia’s Bay of Fundy.
(NH, 2/05, p.p.16)
c355Mil BC - 344Mil BC In 2002 it was reported
that a 1971 fossil from Scotland, initially believed to be an
extinct fish, was actually a tetrapod, one of the earliest creatures
to have walked on land. It was identified as a member of the
Whatcheeriidae family and named Pederpes finneyae.
(SFC, 7/4/02, p.A3)
354Mil BC - 290Mil BC Carboniferous period. The
first great forests and amphibians appear. This period is broken
into two parts for N. America, the Mississippian and Pennsylvanian).
Hylonomous was one of the first reptiles. It resembled its amphibian
ancestors but laid its eggs on land. Its skull and limb girdles were
more robust than that of an amphibian. Its fossils are found in the
Joggins formation at the base of the upper carboniferous in Nova
350Mil BC Time of the Caledonian orogeny in
350Mil BC The initial uplift that formed the Green
Mountains of the Appalachians took place about this time.
(NH, 7/96, p.54)
350Mil BC Plants first developed seeds about this
(SFC, 11/27/98, p.A2)
350Mil BC Vertebrates colonize land. Edwin H.
Colbert (d.2001), paleontologist, later authored "Colbert’s
Evolution of the Vertebrates."
(NG, V184, No. 4, Oct. 1993, R. Gore, p.124)(SFC,
350Mil BC The oldest order of terrestrial
vertebrates, Caudata, can be traced back to before this time.
(PacDis, Winter ’97, p.36)
350Mil BC Cockroaches have survived basically
unchanged since this time. They represent 40% of the Permian insect
fossils in what has been dubbed the "Age of Cockroaches."
(PacDis, Spring/'94, p. 45)
c350Mil BC - 320Mil BC Romer’s Gap. The fossil
record for tetrapods was empty. [see 354-344 Mil]
(SFC, 7/4/02, p.A3)
350Mil BC - 270Mil BC The amphibians, newts,
salamanders and frogs are all that remain today of a group that
became highly successful and varied in the Carboniferous and Permian
periods. The rise of the insects provided a generous food supply.
The amniote egg allowed the animal to develop to a stage resembling
a fully grown adult gave freedom from the watery environment.
The first amniotes were small, apparently
secretive insect eaters. The remains of the earliest representatives
were found inside fossilized trunks of hollow Nova Scotia logs.
(NH, 6/96, p.41)
Over vast area of the Carboniferous sea floor the
crinoids, the delicate, stalked, flower-like group of echinodermata,
lived by the millions, raising their fragile calyces as much as a
meter from the bottom.
From an atmosphere rich in carbon dioxide the
growth of the Carboniferous forests may have removed much of it in
exchange for oxygen.
In North America forests covered about 260,000
sq. km. of the mid-continent; in Europe perhaps 100,000 sq. km.
Early in Carboniferous time the North American
continent seems to have slid quietly under the waves to an extent
scarcely matched before or since. For a very brief period there was
stagnation... and it became an expanse of dead, still water. Slowly
the waters became populous again... and from the North-west
territories of Canada to Mexico and from the Pacific ocean to east
of the Mississippi there was once again a shallow sea, the Madison
Sea. This was the last of the great Paleozoic floodings of the N.
It was a period during which the plant kingdom
reached an unprecedented luxuriance. Periodic salt water flooded
coastal marshes and killed off the plant growth. Accumulation of
carbonaceous material settled over time to produce peat, lignite and
coal in turn. Multiple cycles of climate and or earth movement
caused a varying proportion of marine and non-marine sediment to
accumulate, which can be measured and which suggest where land and
sea lay. The cycles are called cyclothems.
350Mil BC - 200Mil BC Glacial conditions during
the Permo-Carboniferous times laid down a series of rock sediment in
all the southern continents, Australia, Antarctica, India, Africa,
and South America. It is called the Dwyka series in Africa and
occurs over much of the country between the southern cape and the
equator. In many places they are 600 meters thick. A continental
polar region answers the demands nicely with glaciers carrying
debris off radially from around the pole.
The Gondwana glaciations and the Glossopteris
forests stretched into what is now eastern India where, again, the
ice was moving northwards. In South and East Africa the ice spread
northwards as far as Lake Victoria on the present equator. There may
have been as many as five major glacial ages with warmer spells
between. Between the long cold periods, Glossopteris forest occupied
the well-watered lower regions in South America as it did on the
eastern side of Gondwanaland.
As many as eleven successive old moraine
deposits, one upon another, are known in Australia. The Paleozoic
glacial chill may have lasted 20 million years.
345Mil BC - 320Mil BC Mississippian Period.
345Mil BC - 280Mil BC A hypothesis was proposed by
Gans et al of the Univ. of Michigan that an oxygen pulse occurred
during the late Paleozoic. An increase of atmospheric oxygen
concentrations from 15-35% may have lasted for about a 100 million
years. Today the atmosphere contains about 21% oxygen. The idea is
supported by the extraordinary number of new species documented
during this period. A dense atmosphere would promote insect flight
and primitive lung effectiveness.
(LSA., Fall 1995, p.20)
345Mil BC - 230Mil BC Mississippian,
Pennsylvanian, Permian. Bear Valley Ranch in Inverness ridge:
Quarry, white limestone. Road cuts 12 miles south of Carmel along
Highway 1: white limestone. Road cuts between Big Sur and Lucia
along Highway 1: mica-rich metamorphic rocks. Metamorphic rocks of
Calaveras Formation at the Geologic exhibit along Yosemite Highway 6
miles east of Briceburg.
330Mil BC The body impressions of salamander-like
creatures, estimated to be 330 million years old, were later found
in sandstone rocks collected in eastern Pennsylvania and stored in
the museum in Reading, Pa.
UPPER CARBONIFEROUS: PENNSYLVANIAN PERIOD 320 - 280 Million Years
(E&IH, 1973, p.42)
320Mil BC Reversing Falls in the Bay of Fundy, New
Brunswick, Canada, dates to this time and is where at high tide
surging salt water reverses the fresh water of the St. John River up
48 feet at high tide.
(SFEC, 5/25/97, p.T7)
320Mil BC - 280Mil BC Pennsylvanian Period.
320Mil BC - 240Mil BC The male Y and female X
chromosomes evolved from ordinary chromosomes over this period.
(SFC, 6/19/03, p.A11)
315Mil BC In 2007 scientists dated plant and
insect specimens from a limestone cave in Illinois to about this
312Mil BC Spider-like creatures called
trigonotarbids lived during this time. They had 8 legs but lacked
spinnerets. In 2009 their images were extracted from rock using
high-resolution X0ray micro-tomography.
(Econ, 8/8/09, p.70)
310Mil BC Animals developed that produced eggs
with watertight membranes that allowed reproduction on land.
(NYT, 6/7/96, p.B1)
310Mil BC The common ancestors of birds and
mammals diverged about this time. A report in Nature, Apr 30, 1998,
traced development back using a "molecular clock."
(SFC, 4/30/98, p.A1,13)
310 Mil BC Fossils of 2 spider species from
Coseley, England, Eocteniza silvicola and Protocteniza britannica,
dated to about this time.
300Mil BC Indiana was a sea floor upon which
rained the skeletons of fossils that later formed into limestone.
(Nat. Hist., 4/96, p.50)
300Mil BC In 2009 researchers in Kansas found the
fossilized brain of an iniopterygian fish dating to about this time.
The fish is a relative of modern ratfishes, also known as ghost
(SFC, 3/3/09, p.A5)
300Mil BC A shark from the Edestus genus swam the
seas over what later came to be known as Kentucky, USA. A fossilized
black jawbone, believed to be from the shark, was found in 2011 in a
central Kentucky mine.
300Mil BC The waters of the Rio Negro rise in the
Guinea shield of northern South America, which is more than 300
million years old.
(Hem, 9/04, p.32)
300Mil BC The fossil record later indicated that
cycad plants have been around since at least this time.
(SFC, 11/14/07, p.G2)
300Mil BC The Helicoprion (spiral saw), a
cartilagenous fish with a tooth whorl, inhabited the seas around
(NH, 3/1/04, p.76)
300Mil BC - 250Mil BC Evidence of widespread
former glaciers occurs in strata of this age in eastern South
America, southern Africa, India and Australia. Similar evidence
occurs in Antarctica. This suggests that all these continents were
formerly parts of a single continent which broke into pieces.
(E&IH, 1973, p.93)
Late Carboniferous Much of southern Africa and the
other southern continents was capped by an ice sheet of gigantic
proportions in the late Carboniferous. Between glacial spells of the
Carboniferous, the Glossopteris and other trees covered the land.
290Mil BC A small lizard, later named Eudibamus
cursoris, became the 1st to run on 2 legs. It lived the Laurasia
continent and was discovered in 2000 in Germany.
(SFC, 11/3/00, p.A1)
290Mil BC If there had ever been a Paleozoic
proto-Atlantic it would seem to have been closed up by about 290
million years back.
290Mil BC A fish called Acanthodes bronni, part of
the acanthodian group of fish, which included the earliest
vertebrate animals with jaws, lived about this time. This fish was
among the first to split from sharks, whose bones are made of
cartilage, to evolve into a line of tough-boned species that later
included everything from bony fish to human beings.
Permian Period 290 - 248 Million Years Ago
Lower Permian Red Beds in Texas and Oklahoma have
fossils of the fin-backed reptile, Dimetrodon, which belong to the
group called pelycosaurs. They were probably the first stage in the
development of mammals from reptiles. These meat eater had teeth of
different sizes, long at the front and short in back. The sail-like
fin was probably was probably an early stage in the development of
c285Mil BC The southern part of the Appalacian
ocean and the Hercynian ocean were closed in the late Carboniferous
and Permian periods.
280Mil BC Early Permian in mountains near Las
Cruces, New Mexico, where a tidal flat at the edge of an inland sea
allowed fossil footprints to form and leave tracks of over 50
(NG, March 1990, Geographica)
270Mil BC - 210Mil BC The Karoo Basin in South
Africa, first took shape in the late Carboniferous and lasted about
60 million years. It is filled with fluvial, lake and swamp deposits
including coals. At the end of this period were great outpourings of
basalt in the region, when lava flows covered much of the basin to a
depth of 1,000 meters, the Drakensberg lavas.
On top of the glacial formations comes a coal
measure sequence. The Ecca formations are about 1800 meters in total
thickness and contain many beds of thick coal. These were deposited
in the Permian.
This basin subsided beneath layer upon layer of
sedimentary deposits. At least 7000 meters of continental sediments
were deposited here between late Carboniferous and mid-Triassic
270Mil BC - 225Mil BC Reptiles arrived during the
Only a few species of trilobites were alive in
the Permian period and none are known from later rocks.
In Permian times there was a progressive drying
up of the whole continental area (of Gondwanaland). Wide areas of
the old shields in Australia and South America were flooded by the
shallowest of seas, and when from time to time these were cut off
and desiccated, deposits of dolomite, anhydrite and salt were left
behind. The ice persisted later in Australia where it stayed till
late Permian time.
The Appalachian orogeny seems to have been
concentrated into the Permian period in North America. The fierce
volcanic activity widespread in Europe was not extended into the
west. All of Europe and North America became land. In central Europe
and parts of Russia, in the high Arctic areas of Canada and Siberia
and parts of the southern USA there were limited shallow, very salty
seas. Coral and algal reefs and shell banks sprang up in some parts
of the seas, notably in Texas and new Mexico, and in the lagoons
deposits of gypsum and salt were precipitated.
Upper Permian Beaufort sandstones of South Africa
have fossils of the mammal-like reptile Lycaenops. Its body was
dog-like with its legs under its body. It had long killing teeth at
the front and shearing teeth at the back. It was a large group with
size ranging from a few cm. to some as large as a cow. The larger
ones tended to be plant eaters.
270Mil BC - 180Mil BC Wandering over the
Permo-Triassic countryside were different kinds of mammal-like
reptiles that did not survive the Triassic period. Mesosaurus, a
small aquatic reptile, is present in Permian rocks in both South
Africa and South America.
260Mil BC Scientists in 2011 reported the
discovery of the remains of a saber-toothed vegetarian. The
leaf-crunching animal, about the size of a large dog, lived 260
million years ago in what is now Brazil. Its upper canine teeth were
nearly 5 inches long.
260Mil BC The earliest dicynodonts known are from
remains discovered in Russia and South Africa and date back to this
time. They were the first vertebrates to have become diverse and
efficient herbivores. They were the first to evolve sliding jaws for
crushing plant tissue. The contemporary sail-finned pelycosaurs were
also herbivores but they could only chop off pieces of plants and
bolt them down.
(Nat. Hist., 3/96, p.52-53)
260Mil BC - 250Mil BC In 2005 scientists reported
that a steady decline in the number of living species occurred
during this period followed by a sudden plunge 250 million years
ago. The interval corresponded to a period of prolonged volcanic
activity over a third of Siberia.
(SFC, 1/21/05, p.A4)
260Mil BC - 240Mil BC In 2005 scientists reported
that plummeting oxygen levels over a period of 20 million years
directly contribute to the “Great Dying” centered around 250 million
(SFC, 4/15/05, p.A2)
255Mil BC At the end of the Permian a total of 35
dicynodont genera are known to have existed.
(Nat. Hist., 3/96, p.54)
c255Mil BC Most of some 25 groups of distinctive
echinoderms perished before the age of dinosaurs.
(NH, 12/98, p.41)
255Mil BC Proganochelys, the most primitive turtle
known, appeared in the Triassic at about the same time as the
(NH, 6/96, p.38)
255Mil BC - 63Mil BC The Tethys Sea separated a
northern super continent (Holarctica) from a southern super
continent (Gondwana) through much of Mesozoic time.
(LSA, Spg/97, p.6)
254.7Mil BC In 2012 scientists dated the 40km
Araguainha crater, on the border of Brazil’s Mato Grosso and Goias
states, to this time. They believed that the release of oil and gas
from the impact of a meteorite led to the great Permian extinction.
(Econ, 7/27/13, p.64)
253Mil BC In 2008 scientists reported finding
cellulose dating back to this time, along with some possible ancient
DNA, in salt crystals from an underground nuclear waste dump in
southern New Mexico.
252Mil BC The worst mass extinction in Earth’s
history occurred about this time. 90% of Permian genera of sponges,
corals and brachiopods vanished. 70% of land animals disappeared
within a million years due to a suspected asteroid impact. This was
later called the "Permian-Triassic Extinction" and "The Great
Dying." Scientists later suspected that an eruption of flood basalt
in Russia, the Siberian Traps, caused the massive extinction. In
2004 scientists suggested that the extinction was caused by a
meteorite that hit the north coast of Pangea, forming a crater known
as the Bedout High, later a part of the Australian continent. In
2005 evidence was presented that the extinction was caused by
massive and prolonged volcanic activity. [see 260, 225 and 200
(Econ, 11/8/03, p.78)(SFC, 5/14/04, p.A1)(SFC,
1/21/05, p.A4)(Econ, 2/23/08, p.100)
250Mil BC In 2006 an apparent crater as big as
Ohio was found in Antarctica. Scientists thought it was carved by a
space rock that caused the greatest mass extinction on Earth about
250Mil BC South China at this time was a large
island just north of the equator with a tropical climate. In 2010 a
smattering of fossil land plants from a mountain in Luoping
suggested that the local marine community lived near a conifer
250Mil BC Onychophorans, velvet worms, become land
dwellers and survive today in dark, moist habitats like the floor of
the Costa Rican forest. Probably related to the Burgess shale
Aysheaia. The onychophorans are among the few animals other than
mammals with placentas, and give live birth.
(NG, V184, No. 4, Oct. 1993, R. Gore, p.136)
250Mil BC Coiled tubes in the 250 million year old
rocks of the Karoo region of South Africa indicate the presence of
Diictadon galeops, a far-distant relative of mammals. The adults
were the size of small dogs with long slinky bodies and are thought
to have made the burrows along river banks for brooding. They
belonged to a group of animals known as dicynodonts, and most were
squat, barrel-bodied, lumbering beasts that ranged from rat to hippo
size. The Karoo region at this time was a vast plain crisscrossed by
rivers the size of the Mississippi.
(Nat. Hist., 3/96, p.50,52)
250Mil BC The fossil of the first known reptile to
fly, Coelurosauravus jaekeli, revealed a membrane that stretched
between hollow rods that grew out from the skin on its sides. In
every other animal that flies wing support draws on the normal
(SFC, 3/7/96, p.A9)
250Mil BC It was reported in 2000 that scientists
had brought to life 4 strains of bacteria entombed in salt crystals
of New Mexico rock for 250 million years.
(SFC, 10/19/00, p.A1)
250Mil BC - 200Mil BC The Chinle Formation of
sedimentary rock was laid down by rivers in much of New Mexico and
Arizona during this period. In 2007 scientists reported that fossil
bones found in the Chinle Formation indicated that dinosaurs and
their early relatives lived side by side for millions of years
before the relatives died off leaving dinosaurs to dominate.
(SFC, 7/20/07, p.A4)
250Mil BC - Present: Marine scientists say that 8 extinctions
occurred in the seas over this period at intervals of about 26
(SFEC, 9/7/97, Z1 p.5)
c248Mil BC In 2003 Richard Ellis authored "Sea
Dragons," which focused on ocean life of this time.
(WSJ, 10/24/03, p.W8)
248Mil BC - 206 Million Years Ago Triassic Period
The 1st period of the Mesozoic
248Mil BC - 65Mil BC Mesozoic Era
245Mil BC The reconstruction of a scene from this
period is featured and shows 2 grazing Lystrosaurus and a lurking
Moschorhinus in an environment of a fern and cycad lined river.
(Nat. Hist., 3/96, p.47)
245Mil BC At the beginning of the Triassic, the
sole dicynodont genus that persisted was Lystrosaurus.
(Nat. Hist., 3/96, p.54)
245Mil BC Researchers in 2006 said floodwaters
likely overflowed river banks in parts of Antarctica about this
time, sending water and sand across the landscape and into various
animal homes, such as burrows. No animal bones or remains were found
inside the burrows, suggesting the burrow dweller must have escaped
the deluge. The burrows' sizes and shapes, along with associated
scratch marks, are nearly identical to tetrapod burrows found in
South Africa also dating to the Triassic.
245Mil BC In 2012 dinosaur hunters searching
through museums discovered fossils of Nyasasaurus parringtoni from
eastern Africa that dated to about this time. The creature was
slightly larger than a Labrador retriever, but with a tail over 5
(SFC, 12/18/12, p.A1)
240Mil BC Fossils of Atopodentatus unicus, an
aquatic reptile, roamed the seas about this time. It was identified
in 2014 from fossils found in the Luoping formation of China’s
(Econ, 3/29/14, p.86)
230Mil BC A small 4-foot-long, 10-15 pound
dinosaur, later named Eodromaeus (dawn runner), inhabited South
America. Its fossils were discovered in the 1990s in northeastern
(SFC, 1/14/11, p.A6)
c230Mil BC It was reported in 1999 that dinosaur
fossils, found 4 years earlier in Madagascar, might be the oldest
known. The creatures were long-necked prosauropods from about this
(SFC, 10/22/99, p.A1)
230Mil BC The Panthalassa Ocean covered much of
what later became the western United States. Sediments later called
the Luning Formation were deposited in what later became the
mountain ranges of central Nevada. Fossil ichthyosaurs included
230Mil BC A long-necked dinosaur called
Dinocephalosaurus orientalis, dated to this time, was discovered in
China in 2004. Scientists speculated that the long neck might have
functioned like a vacuum to suck up unsuspecting fish.
(SFC, 9/24/04, p.A2)
228Mil BC Paleontologist Paul Sereno led a team in
the Andes that discovered a small dinosaur species called Euraptor.
(SFC, 5/17/96, p.A-3)
225Mil BC Icthyosaur fossils first found in 1928
by prof. Seimon W. Muller of Stanford 150 miles SE of Reno, dated to
this time. An inland sea linked to the Pacific and submerged
California and Nevada during the Triassic.
225Mil BC A 3rd known and most violent mass
extinction ended the Paleozoic Era. Some 95% of all species vanished
including the trilobites. This was the time that Pangea formed with
declining sea levels and massive volcanic eruptions. [see c251 &
(SFEC, 8/22/99, Par p.12)
225Mil BC - 65Mil BC Dinosaurs were both numerous
and varied in California. In 2003 Richard P. Hilton authored
“Dinosaurs and Other Mesozoic Reptiles of California.” California
was under water at the beginning of the Mesozoic (255-63). By the
end of the era roughly the eastern third of the state had emerged.
(PacDis, Summer ’97, p.26)(CW, Winter 04, p.51)
220Mil BC In Kyrgyzstan the fossil of a birdlike
reptile from this time was found around 1970. The reptile was named
Longisquama insignis and its evolution appeared to precede the
development of dinosaurs. The imprint of feathers and hollow shafts
related it to modern birds. The feather imprints were later claimed
to just thick scales.
(SFC, 6/23/00, p.A1)(SFC, 11/23/00, p.A14)
220Mil BC Eomaia scansoria (eomaia = dawn mother),
a primitive shrewlike creature, may have diverged from the
monotremes and marsupials about this time. [see 125 Mil]
(SFC, 4/25/02, p.A2)
220Mil BC Bacteria and single-celled animals and
plants from this period became encased in tree resin on the northern
edge of the Tethys Ocean. Scientists in 2006 studied the organisms
in amber of this time from a town in the Italian Dolomites. Ciliates
and amoeba in the amber appeared identical to modern examples.
(Econ, 12/16/06, p.84)
215Mil BC In 2009 paleontologists reported
the discovery of a small feathered dinosaur that lived about this
time in New Mexico. The carnivorous beast was about 28 inches tall
and about 6 feet long and contained air sacs along its backbone,
neck and head. It was named Tawa hallae after a Hopi Indian sun god
and amateur paleontologist Ruth Hall.
(SFC, 12/11/09, p.A15)
215 Mil BC The rocks of northern Tennessee began
to bend under the pressure of continental collision. Oil migrated
from deep in the earth into cracks and folds in the rocks.
(SFC, 9/3/04, p.W4)
210Mil BC By the end of the Triassic after 50
million years on Earth, the dicynodonts were gone. Most likely
climactic changes that caused increased aridity as Pangea drifted
northward toward the equator led to their demise. Only the distant
cousins, the cynodonts, left descendants.
(Nat. Hist., 3/96, p.54)
210Mil BC Scientists in New Mexico in 1947
uncovered fossil rock from this period. In 2005 a close examination
revealed that the fossils looked like a 6-foot long, 2-legged
dinosaur. It was named Effigia okeeffeae and identified as a
reptile, an ancient relative to modern alligators and crocodiles.
(SFC, 1/26/06, p.A2)
210Mil BC The Plateosaurus, a peaceful herbivore
measuring up to 10 meters from head to tail, roamed river deltas in
large herds about this time, when most of Switzerland was covered
with desert and its landscape may have looked much like the estuary
of the Nile now.
208Mil BC - 142Mil BC The reptile called a
Thalattosuchian roamed a tropical environment in Asia about this
time. The amphibious creature represents an early milestone in
evolutionary history, marking a transition during which these
reptiles moved from being semi-aquatic to wholly ocean species.
Scientists In 2007 uncovered the remains of the six- to
eight-foot-long reptile in Jurassic rock on private property in the
Snowshoe Formation of the Izee Terrane, a rock formation in Oregon.
The rock-entombed animal migrated eastward via continental drift.
206Mil BC - 144Mil BC Jurassic
In 1996 a Jurassic dinosaur fossil was found in a
limestone block in Saltrio, Italy, near the Swiss border. The
saltriosaur, a 3-fingered, meat-eater, was 26.4 feet long and
weighed over a ton.
(SFC, 11/10/00, p.A14)
Almost all the road cuts in San Francisco:
sandstone, shale, chert, dark igneous rock, serpentine date to the
Jurassic. Roads north of Golden Gate and in Mt. Tamalpais State
Park: sandstone, shale, chert, basalt. Skyline Drive from Milbrae
turnoff south to Woodside: Sandstone, shale, dark igneous rock,
serpentine. Mariposa slates near Mariposa in the Sierra Nevada.
201.4Mil BC A mass extinction occurred about this
time. In 1999 it was reported that a titanic volcanic eruption
occurred about this time and split an ancient super-continent. This
process began the formation of the Atlantic Ocean. Half of all
marine species died in a few million years. [see 252 and 225 mil]
(SFC, 4/23/99, p.A3)(Econ, 11/8/03, p.78)(Econ,
200Mil BC Teleosts, ray-finned fishes, first
(NH, 6/96, p.37)
200Mil BC Quarter-inch-long saw flies were members
of a family that remained unchanged since this time.
(PacDis, Winter/’96, p.43)
200Mil BC A fossil of the winged Icarosaurus
siefkeri reptile, dating to about this time, was found in a black
shale New Jersey quarry in 1961. It was sold at auction in 2000 for
$167,500 and donated to the American Museum of Natural History in
(SFC, 7/17/00, p.A1)(SFC, 8/28/00, p.A1)
200Mil BC In 1983 Paul C. Sereno first viewed
fossils of Pegomastax, a member of the heterodontosaur family and
one of the smallest dinosaurs that ever lived, in a slab of red rock
that was collected in the early 1960s by scientists working in South
Africa. In 2012 Sereno, a paleontologist at the Univ. of Chicago and
a dinosaur specialist, described the strange anatomy of the
specimen, which dated back some 200 million years, and gave the new
species the name Pegomastax africanus (thick jaw from Africa).
198Mil BC In 2002 scientists presented research
that indicated a cataclysm about this time in the Triassic due to a
comet or asteroid that killed of species competing with dinosaurs.
Iridium deposits and fern spores were cited as evidence.
(SFC, 5/27/02, p.A6)(SFC, 3/19/04, p.A5)
197Mil BC In 2009 Scientists in South Africa said
that a newly discovered dinosaur species that roamed the Earth about
this time may help explain how the creatures evolved into the
largest animals on land. The Aardonyx celestae was a 23-foot-
(7-meter-) long small-headed herbivore with a huge barrel of a
chest. The species walked on its hind legs but could drop to all
197Mil BC - 190Mil BC A bed of
embryo lufengosaurus bones in southern China, reported in 2013,
dated to this period.
(SFC, 4/19/13, p.D7)
c195Mil BC A tiny animal the size of a paper clip
from fossil beds in China’s Yunnan province dated to this time. It
was named Hadrocardium wui in 2001 and was considered as a possible
ancestor to all living mammals.
(SFC, 5/25/01, p.D8)
190Mil BC In 2008 scientists discovered numerous
dinosaur footprints dating to this time at the Vermilion Cliffs
National Monument along the Utah and Arizona state border.
(SFC, 10/22/08, p.A4)
190Mil BC A 4th mass extinction occurred at the
end of the Triassic. Lake Manicouagan in Quebec, a 60-mile crater,
was formed by a cosmic impact that may be related to the extinction.
Cotylosaurs, a possible missing link between mammals and reptiles,
(SFEC, 8/22/99, Par p.12)
190Mil BC Dinosaur embryos from this time were
unearthed in South Africa in 1973. They belonged to a plant-eating
group called prosauropods named Massospondylus (bulky vertebrae)
first discovered by Richard Owen in 1854.
(SFC, 7/29/05, p.A2)
180Mil BC Fish shared the seas with marine
crocodiles and plesiosaurs and were hunted by winged pterosaurs.
(NH, 6/96, p.41)
180Mil BC Sediments of this time from a deep sea
habitat teeming with life were later pushed up into what became
known as the Glasenbach Gorge in the Austrian Alps.
(Econ, 5/24/14, p.74)
180Mil BC - 135Mil BC The plesiosaurs were a group of swimming
reptiles that developed early in the Jurassic into to main lines,
the elasmosaurs and pliosaurs. The elasmosaurs were described by
Dean William Buckland as "snakes threaded through turtles." The
pliosaurs had big heads with short necks and their bodies reached
immense sizes. The pliosaur Peloneustes lived rather like today’s
toothed whales, feeding mainly on large cephalopods.
180Mil BC - 135Mil BC Pangaea, however, was
short-lived. With the extension of the great ocean, Tethys, it split
into Laurasia and Gondwanaland. Then in Jurassic and Cretaceous
times the Atlantic ocean made its appearance while Gondwana broke up
180Mil BC - 135Mil BC A branch gulf had
begun to open and edge north-western Spain away from Brittany. There
was new growth of the ocean floor between North America, South
America and Africa. Much of the western half of the continent was
flooded by shallow seas.
180Mil BC - 135Mil BC Along the western
coastal area of North America it seems likely that for part of the
time there was a long, narrow island running parallel to the edge of
the continent from Alaska to Mexico. Dinosaurs and marine reptiles
have left their bones in this region. The Nevadan orogeny was now
180Mil BC - 135Mil BC In Antarctica there is
a Jurassic legacy of volcanic rocks and some sand-stones remarkably
full of plant remains.
180Mil BC - 135Mil BC Great piles of
volcanic lavas and ashes in parts of western North America and
around the Red Sea occur from the Jurassic.
180Mil BC - 135Mil BC The Mesozoic reef
builders did not appear until as late as the Jurassic in most parts
of the world.
180Mil BC - 135Mil BC Along the eastern
seaboard of Brazil and the west coast of Africa are several thick
deposits of late Jurassic and early Cretaceous date. The sedimentary
characters and fossils (ostracods, tiny active creatures with a
bivalve shell) in these rocks indicate bodies of fresh water.
180Mil BC - 135Mil BC During the Jurassic
period the shells of the ammonites grew in some cases to 50 or 60
cm. and were strengthened and corrugated by all manner of ribs,
ridges and knobs.
180Mil BC - 135Mil BC The more efficient
pterodactyls or pterosaurs of the Jurassic had wing membranes
supported by the tremendously long fourth fingers.
180Mil BC - 70Mil BC Dinosaur fossils of this age
were later found in the El Chocon region of Patagonia, Arg. They
included the plant-eating Gasparinisaura.
(NG, 12/97, p.123)
175Mil BC The EETA 79001 meteorite, identified to
be from Mars, was estimated to be this age. It blasted from Mars
into space about 600,000 BC.
(SFC, 11/1/96, p.A16)
170Mil BC In 2004 scientists reported the
discovery in Antarctica of primitive sauropod, a plant-eating
dinosaur, from this time.
(SFC, 2/27/04, p.A2)
170Mil BC In northern California magma burbled up
through older, softer rock and formed a granite pluton. Wind and
water over the next 100 million years scrubbed the area which later
became known as Castle Crags.
(SSFC, 5/14/06, p.G8)
170Mil BC The semi-aquatic platypus is thought to
have split off from a common ancestor shared with humans
approximately about this time. In 2008 scientists laid bare the
platypus genome of 2.2 billion base pairs spread across 18,500
166Mil BC Monotremes split off from ancestral
mammals about this time.
(Econ, 3/31/07, p.88)
165Mil BC Scientists in 2005 announced that tracks
of a previously unknown swimming dinosaur have been found along the
shores of an ancient sea in Wyoming. The tracks reveal an event when
a six-foot-tall, two-legged dinosaur waded into the inland sea and
gradually lost touch with the ground. It was about the size of an
ostrich, and it was a meat-eater.
165Mil BC Middle Jurassic Oxfordian Beds have
fossils of Metriorhynchus. It was a marine crocodile of the group
Thalattoschia. Its legs had become swimming paddles and its body had
become long and sinuous. It did not have bony plates and its tail
flattened out at the end to support a triangular swimming fin.
165Mil BC Madagascar broke away from the
continent of Africa. [see 160 mil BC]
(SFC, 1/15/98, p.A10)
165Mil BC The spider named Nephila jurassica dated
to this time. A fossil of the spider, about as large as its modern
relatives, was discovered buried in ancient volcanic ash in Inner
Mongolia, China. Tufts of hairlike fibers seen on its legs showed
the arachnid to be the oldest known species of the largest
web-weaving spiders alive today, the golden orb-weavers, or Nephila,
which are big enough to catch birds and bats, and use silk that
shines like gold in the sunlight.
165Mil BC-125Mil BC Fossils of fleas, from this
period in China, were described in 2012 as being nearly an inch long
and having a proboscis with serrated edges for biting and feeding.
(SFC, 3/1/12, p.A2)
164Mil BC In 2006 a fossil from
this time found in Inner Mongolia in China was reported to have been
a mammal with a flat, scaly tail like a beaver, vertebra like an
otter and teeth like a seal that swam in lakes eating fish. The new
animal, about the size of a small female platypus, is not related to
modern beavers or otters but has features similar to them. The
researchers named it Castorocauda lutrasimilis.
163Mil BC - 144Mil BC Rhamphorhynchus, a
crow-sized flying reptile species, had a 3-foot wing span and 4-inch
skull and lived in Europe during this period.
(SFC, 10/30/03, p.A5)
160Mil BC A crested dinosaur with probable
feathers inhabited northwestern China about this time. A fossil of
the 10-foot long relative of Tyrannosaurus rex, later named Guanlong
wucaii, was found in 2004.
(SFC, 2/9/06, p.A5)(WSJ, 2/9/06, p.A1)
160Mil BC A flying reptile called Darwinopterus
modularis, later discovered in China’s Liaoning province, dated to
this time. It was believed to be an example of a flying reptile in
transition from a more primitive long tailed form exemplified by
Rhamphorhynchus and the tailless creatures typified by Pteranodan.
In 2011 the specimen was identified as a female carrying an egg
seemingly designed for burial.
(Econ, 10/17/09, p.96)(Econ, 1/22/11, p.96)
160Mil BC The fossil of 10-foot dinosaur of this
time was later discovered in northwestern China. In 2010 scientists
said that the Haplocheirus sollers (simple, skillful hand) had short
forearms, massive claws, 3 toes, a long beak, a keel-shaped chest
and was a member of a family, the Alvarezsaurs, that evolved into
(SFC, 1/30/10, p.A10)
160Mil BC Madagascar broke away from the
continent of Africa. [see 165 mil BC]
(WSJ, 9/8/00, p.W6)
160Mil BC A collision likely occurred in the
asteroid belt orbiting the sun about 100 million miles from Earth.
One of these asteroids was later named Baptistina. In 2007 US and
Czech researchers used computer simulations to calculate that there
was a 90 percent probability that the collision of two asteroids,
one about 105 miles wide and one about 40 miles wide, was the event
that precipitated the Earthly disaster of 65Mil BC, when an asteroid
hit the Earth on Mexico’s Yucatan peninsula. They said another
fragment likely created the Tycho crater on the moon at about 110Mil
(Reuters, 9/5/07)(SFC, 9/6/07, p.A14)(Econ,
155Mil BC - 150Mil BC In mid-Jurassic rocks of
Germany occurred the very rare remains of Archaeopteryx, widely
considered as the earliest known bird. It was about the size of a
dove, had a long, reptile-like tail but with real feathers, not
scales, and it possessed teeth in its beak. The first Archaeopteryx
fossil turned up in 1861.
(Econ, 11/10/07, p.101)(SFC, 7/28/11, p.A8)
154Mil BC Holger Luedtke, an amateur fossil
hunter, found in 1998 the fossils of small dinosaurs in a quarry in
Germany’s Hartz mountains. They were later identified as a new
species from this time and named Europasaurus holgeri.
(SFC, 6/8/06, p.A7)
152Mil BC In 2004 a Swiss paleontologist said
hundreds of dinosaur prints dating back this time had been
discovered in the Jura mountains in the northwest of Switzerland.
150Mil BC A small, chipmunk-sized mammal named
Fruitafossor windscheffeli lived in Colorado. It developed heavy
forearms for digging in the ground to feed on insects and termites.
(SFC, 4/1/05, p.A4)
150Mil BC Upper Jurassic Morrison Formation in
Colorado has fossils of Apatosaurus, once known as Brontosaurus. Its
name means headless lizard because early specimens lacked a head. It
roamed forested plains and swamps in herds but probably spent most
of its time in shallow waters. Tiny peg-like teeth were used for
water weeds. It reached 20 m in size and weighed as much as 30 tons.
A head was finally found in 1979 and was found to be quite long and
slender. O.C. Marsh, paleontologist, described a large dinosaur in
1877 that he called Apatosaurus ajax (deceptive lizard) based on a
newly discovered vertebral column. In 1879 he discovered the bones
of a larger beast that he named Brontosaurus (thunder lizard). In
1903 Elmer Riggs showed that Apatosaurus was just a younger
(TE-JB, p.64-65)(SFEC, 5/30/99, Par p.12)
150Mil BC Upper Jurassic Morrison Formation in
Colorado and Wyoming has fossils of Ceratosaurus. It is also found
in East Africa. It was a flesh-eating carnosaur that stood on two
feet with the body held forward and balanced by the long stiff tail.
It had a battery of fierce teeth, a horn on its nose, heavy ridges
above the eyes, and a jagged crest down the back. Great claws on the
hind limbs and smaller ones on the fore limbs were used to kill its
prey which it hunted in packs. It stood 6 m.
150Mil BC Upper Jurassic Morrison Formation in
Colorado has fossils of Stegosaurus. The array of plates down its
back were not attached to the main skeleton but only embedded in the
skin and could have lain flat or upright, in pairs or alternate.
Their function is not understood. It was 9 m long and stood 2.5 m at
150Mil BC The small dinosaur Fruitadens haagarorum
lived about this time in Colorado. It weighed less than 2 pounds and
measured 28 inches from its little jaws to the end of its tail. Its
fossils were found in the late 1970s near Fruita, Colo.
(SFC, 10/21/09, p.D2)
150Mil BC Upper Jurassic Morrison Formation in
Utah has fossils of Diplodocus. Its 28 m length included a 14 m tail
and an 8 m neck. It stood 4 m at its hips. Its vertebrae combined
struts and hollows making it light and strong. The rear feet had
three claws and the front had one. It was a plant-eater and also
found near Thermopolis, Wyo.
(TE-JB, p.66)(SFEC, 4/27/97, p.T1,5)
150Mil BC In 2008 the Bureau of Land Management in
Utah announced a dinosaur find, calling the quarry near Hanksville
"a major dinosaur fossil discovery." An excavation revealed at least
four plant-eating dinosaurs and two carnivorous ones dating back to
about 150 million BC.
150Mil BC In 1989 a fossil egg from this time in
Utah was found by CAT scan to contain the oldest dinosaur embryo.
150Mil BC Upper Jurassic Morrison Formation in
Wyoming has fossils of Coelurus, a member of the Coelurosauria. It
had three fingers and stood 2 m and was once called Ornitholestes
(bird-robber) for it is thought to have pounced after birds.
150Mil BC Fossils of a sauropod named Suuwassea
emileae (ancient thunder) were found in southern Montana in 1998. It
was about 50 feet long and related to Diplodocus.
(SFC, 5/21/04, p.A2)
150Mil BC In 2005 archeologists in Montana worked
to unearth a sauropod believed to be from this time making it about
twice as old as most dinosaur skeletons found in the state. It
seemed to represent a missing link in the evolution of the
150Mil BC Upper Jurassic Oxford Clay has fossils
of Cryptocleidus, one of the smaller of the elasmosaurs, swimming
reptiles with snaky necks.
150Mil BC Upper Jurassic Oxford Clay has fossils
of Opthalmosaurus, an ichthyosaur that became very dolphin-like. It
had huge eyes that were supported by a ring of bone that helped it
withstand changes in pressure. Detailed remains show that it gave
birth to live young. It had no teeth and it is supposed that it
caught slow-moving or sleeping prey.. Skin tissues indicate that it
was tortoiseshell colored.
150Mil BC In 1861 upper Jurassic lithographic
limestone at Solenhofen, southern Germany, was found to have fossils
of Archaeopteryx, the feathered dinosaur. It had teeth in its jaws,
claws on its wings and a long bony tail. Its bones were hollow and
light but its muscles were weak and it was not a very good flyer.
Aerodynamic analysis in 1999 indicated that Archaeopteryx could
possibly run to 5 mph and flap enough to glide for some 100 yards.
(TE-JB, p.61)(Hem., 10/97, p.130)(SFC, 5/6/99,
150Mil BC Upper Jurassic Lithographic Limestone of
Bavaria and south-east France has fossils of Compsognathus. It was a
small, meat-eating, coelurosaur dinosaur. It had three toes on long
hind legs and two fingers and was the size of a domestic hen.
150Mil BC Upper Jurassic lithographic limestone at
Solenhofen, southern Germany, has fossils of Pterodactylus, a
pigeon-sized descendant of Podopteryx. Its wings were supported on
elongated and thickened fourth fingers. The effective area of each
wing could be controlled by the spread of the hind limbs. The body
and limbs were covered by a fine fur indicating some sort of body
heat control. A more primitive group was the Rhamphorynchoidea,
which had narrower wings and a long stiff tail. Pterosaurs were
widespread and have been found on all continents except Antarctica.
Pterodaustro scooped plankton from the water. Anurognathus ate
insects. Dimorphodon ate meat. Pteranodon caught fishes. Up to this
time insects with wingspans of more than 2 feet ruled the skies.
(TE-JB, p.62)(SFC, 6/6/12, p.A9)
150Mil BC A small dinosaur later named Juravenator
starki inhabited southern Germany. It was found near Solnhofen and
was similar to coelurosaurs in China, but did not show signs of
(SFC, 3/16/06, p.A5)
150 Mil BC Upper Jurassic Purbeck beds widespread
in England, Europe, Mongolia, N. Africa and N. America show fossils
of Iguanodon. It had a pointed beak and grinding teeth that indicate
that it was a plant-eater.
150Mil BC In 2009 paleontologists in eastern
France reported the discovery of some of the largest dinosaur
footprints ever documented, measuring about 1.4 meters to 1.5 meters
(4.6 feet to 4.9 feet) in diameter. The well-preserved footprints
dating to about this time were found high in the Jura mountains, a
literal sauropod stomping ground.
150 Mil BC In 1999 Norwegian scientists discovered
an undersea meteor crater in the Arctic Ocean 125 miles north of
Norway that dated to this time. It measured 25 miles wide. The
meteor was estimated at 1 1/4 mile wide traveling at 18,600 mph.
(SFC, 2/9/99, p.A10)
150Mil BC In 2006 researchers in Norway announced
the discovery of the remains of a short-necked plesiosaur, a
prehistoric marine reptile the size of a bus, that they believe is
the first complete skeleton ever found. The 150 million year old
remains of the 33-foot ocean going predator were found on the remote
Svalbard Islands of the Arctic. Researchers in 2008 said it was the
biggest of its kind known to science with dagger-like teeth in a
mouth large enough to bite a small car.
(AP, 10/5/06)(Reuters, 2/27/08)
150Mil BC In 2006 scientist reported finding
fossils of a large sauropod in Spain from this period. It was named
Turiasaurus riodevensis, and estimated to have weighed between 40
and 48 tons.
150Mil BC In 2008 scientists said footprints,
dating from about this time, showed sauropods traveling at the same
speed along a river in Yemen, the first discovery of dinosaur
footprints on the Arabian peninsula.
150Mil BC - 145Mil BC The Santiago Peak Volcanics
took place in southern California.
150Mil BC - 145Mil BC Most of the dinosaur fossils at Thermopolis,
Wyo., were from this period. The area had a humid, tropical climate
with many streams. Diplodocus, Monolophosaurus, and Camarasaur, a
60-foot-tall plant-eater, were some of the creatures found.
(SFEC, 4/27/97, p.T1,5)
148Mil BC Marsupials parted company with placental
about this time.
(Econ, 3/31/07, p.88)
146Mil BC The great sauropods dwindled by the end
of the Jurassic, at least in North America, and were supplanted by
smaller ornithischian (bird-hipped) dinosaurs, such as the
hadrosaurs and ceratopsians.
(NG, 12/97, p.129)
145Mil BC Late in the Jurassic there was
widespread uplift along the west coast of South America, and it was
a signal for vigorous volcanic uproar.
145Mil BC The Late Jurassic ended as the
present-day continents began to split off from Pangaea.
(SFC, 5/17/96, p.A-3)
145Mil BC Long necked dinosaurs, the sauropods,
dominated North America and ate large amounts vegetation. They
clear-cut large areas and left the land open to flowering plants and
low shrubs conducive to squat grazers.
(SFC, 10/14/97, p.A9)
145Mil BC The seas over Nevada receded.
(SFC, 12/2/06, p.A6)
145Mil BC - 65Mil BC CRETACEOUS
145Mil BC - 65Mil BC Researchers in 2009 said
fossils from this period, unearthed in what later became the Sahara
desert, revealed a once-swampy world divided up among a half-dozen
species of unusual and perhaps intelligent crocodiles. They lived
during the Cretaceous period, when the continents were closer
together and the world warmer and wetter. They were given snappy
names, such as: BoarCroc, RatCroc, DogCroc, DuckCroc and
142Mil BC In 1998 a fossilized flower was
discovered near Baipiao, China. It indicated pea pods containing
seeds, the fruit of a flower.
(SFC, 11/27/98, p.A2)
140Mil BC Masses of peridotite rock heaved onto
the sea floor from the earth’s crust about this time. It mingled
with seabed sediment and merged with an oceanic plate that slid
toward the Sierra foothills and the Klamath region of northern
California until it hit the North American plate. The peridotite
turned to serpentine under pressure and rose to parallel the San
(CW, Fall ‘03, p.42)
140Mil BC A coelacanth fossil of this age was
found in a quarry in southern West Germany.
(NG, 6/1988, p.833)
140Mil BC Older [DNA] samples have been extracted
from amber--which dates back 140 million years.
(WSUAN, Fall/95, p.5)
140Mil BC The fossil record of the Chinese
sturgeon below the Gezhouba Dam on the Yangtze River dates back at
least this far.
(NH, 7/96, p.38)
140Mil BC Fossils of feathered birds, later called
Confuciusornis, were found in 2002 in Liaoning province, China. They
had bird-like short tales. In 2009 Chinese paleontologists reported
that a small dinosaur named Tianyulong Confuciusi, which lived
during the Cretaceous period, was covered with feather-like
structures -- long before anything like feathers had been believed
to have started developing.
140Mil BC In 2014 researchers said a dinosaur
tooth found in Malaysia is at least 140 million years old and
belongs to a new species within the "bird-hipped" Ornithischian
140Mil BC - 120Mil BC The Archaeoraptor
Lianingensis, a feathered dinosaur, lived about this time.
(SFC, 10/15/99, p.D6)
140Mil BC - 65Mil BC Cretaceous
Road cuts along Route 28 in the Vaca Mountains
(Middle California) are: sandstone, shale and conglomerate; road
cuts in Niles Canyon are: sandstone and shale; the Coast Highway
between Devil’s Slide and Moss Beach: granite; Inverness Ridge:
136Mil BC In 2006 scientist used DNA from spider
proteins trapped in amber, that dated to about 110 million BC, and
concluded that araneoid and deinopoid spiders evolved from a common
ancestor 136 million years earlier. Araneoids produce web strands
with sticky glue. Deinopoids produce dry but strong and entangling
(SFC, 6/23/06, p.A8)
135Mil BC In 1999 scientists reported that
flowering plants known as angiosperms began to thrive about this
time and that the shrub Amborella trichopoda was believed to
represent the earliest species of flowering plants.
(SFC, 8/28/99, p.A4)
135Mil BC In 1999 scientists led by Paul Sereno
reported that they had assembled the fossils of the dinosaur named
Jobaria tiguidensis, a 20-ton Sauropod with spoon-shaped teeth found
in the Sahara Desert of Niger.
(SFC, 11/12/99, p.A4)
135Mil BC A fierce marine crocodile, with a
dinosaur head and a fish-like tail, inhabited a vast southern ocean
that covered much of what became Argentina. Discovery of a fossil
skull with 52 jagged teeth was reported in 2005 for a 12-foot
specimen nicknamed “Godzilla” and chico malo.” It was named
(SFC, 11/11/05, p.A2)(WSJ, 11/11/05, p.A1)
135Mil BC A meat-eating dinosaur species, named
Spinostropheus gautieri, inhabited Niger.
(LSA, Fall/04, p.9)
135Mil BC In 2002 US Astronomers reported sighting
a supernova dubbed SN2002bj, reported to be 135 million light years
away and unique in that it died away in days rather than months.
(SFC, 11/6/09, p.A7)
135Mil BC - 70Mil BC Cretaceous
period. Widespread seas. Coccoliths, tiny fossils composed of
calcium carbonate, in countless million make the pure whitish
limestone "chalk," are extremely widespread in to the early
The grasses did not arrive until the Cretaceous
Nearly all the continent of N. America was
covered by transgressive seas in the Ordovician and the Devonian,
and again in the Cretaceous.
Lower Cretaceous Wealdon Marls on the Isle of
Wright in England have fossils of Hypsilophodon. It was 2 m long and
had bumpy lumps down its back. It had a pointed beak at the front
and grinding teeth at the back that indicate that it was a
plant-eater. Its leg structure indicates that it was well adopted
Lower Cretaceous Cloverly Formation in Montana
has fossils of Deinonychus. It was lightly-built, able to run
swiftly, and had a pair of sickle-shaped claws. It was 3 m long and
grouped remains indicate hunting in a pack. It walked on its third
and fourth toes only. The second carried a huge claw that could be
swung through a 180’. Its remains were found grouped around a plant
Africa, Arabia and India were moving towards the
Tethyan Trench and the Tethys ocean was narrowing rapidly.
Both North and South America reached western
north-south trench system. The effects of this encroachment were
vigorous upheavals in which the Mesozoic ocean sediments were
transformed and began to rise as the great Cordillera.
The super-continent of Laurasia had by the end of
the Cretaceous almost ceased to exist. As the continents separated
so, it seems, were they to suffer what possibly were the most
extensive transgressions to occur in Phanerozoic time.
East from Africa through Turkey, Iran and into
the site of the great Himalayas today, Tethys continued
130Mil BC Afrovenator abakensis, a 27 foot, hunter
(allosaurus) dinosaur thrived in the tropical paradise of what is
now the Sahara desert. The name means "African hunter from In
Abaka," an area of Niger where bones were found c1994. A second
dinosaur, a long-necked grazer, was 60 feet long. It was a sauropod,
akin to a brontosaurus, and similar to animals that lived earlier in
N. America and Asia.
(AP Las Vegas Review, 10-14-94, p.7a)(Video Doc.
The New Explorers, WTTW, Chicago, Skeletons in the Sand, Dr. Paul
130Mil BC Stegosaurus dinosaurs left footprints
near Broome, Australia. The herbivorous dinosaur was 9 feet tall and
26 feet long with a double plated backbone and spiny tail.
(SFC, 10/16/96, p.A10)
130Mil BC Ants emerged from earlier insect forms
with a distinct metapleural gland to fight off fungi and bacteria.
(SFC, 1/29/98, p.A2)
130Mil BC The fossil Sinovenator (Chinese hunter)
dated to at least this time. A member of the troodontid dinosaurs,
it was about the size of a chicken and represented a possible link
to birds. It was discovered in Liaoning province in 2002.
(SFC, 2/14/02, p.A6)
130Mil BC A small Tyrannosaurus rex from this
time, named Dilong paradoxus, was discovered in China in 2004 with
evidence that its body was covered in downy “protofeathers.”
(SFC, 10/8/04, p.A2)
130Mil BC A mammal called Repenomamus robustus
roamed China about this time. In 2005 it was reported that a fossil
of one, the size of an opossum, was found containing the remains of
a young 5-inch psittacosaur in its stomach.
(SFC, 1/13/05, p.A2)
130Mil BC Lines leading to mice and men separated
about this time.
(Econ, 5/31/14, p.71)
130Mil BC - 120Mil BC In 1996 it was reported that
fossils bone were found in a jungle streambed in northeastern
Thailand of a 21 foot tyrannosaur. It was named Siamotyrannus
isanensis. The finding added to evidence that tyrannosaurs evolved
(SFC, 6/20/96, p.C12)
128Mil BC In 2003 scientists reported a 4-winged,
theropod dinosaur from China’s Liaoning province, which they named
(SFC, 1/23/03, p.A2)
128Mil BC - 121Mil BC Chinese paleontologists
found the fossil of a bird-like beast with the impression of
feathers. The feathered dinosaur, a therapod, was about 3-feet long
(SFC, 10/18/96, A9)(SFC, 3/7/02, p.A2)
2 turkey-sized, fossil
dinosaurs with feathers were found in China in 1997 in Liaoning
province. They were distinctly older than archaeopteryx. The birds
were therapods and could not fly. They were named Protarchaeopteryx
robusta and Caudipteryx zoui.
(SFC, 6/24/98, p.A4)
125Mil BC In 2004 Canadian geologists reported the
discovery of dinosaur tracks and a fossilized turtle shell,
estimated to be about 125 million years old, north of Terrace,
125mil BC In 2010 US scientists announced the
discovery of a small, feathered raptor-like dinosaur thought to be
125 million years old in eastern Utah. The Geminiraptor suarezarum
was bipedal and, like other raptors, had a large head.
125Mil BC The 12-foot dinosaur named Falcarius
utahensis of this time was discovered in 2005 in south central Utah
near the town of Green River. It was a primitive member of the
therizinosaurs found in fossil bed in China.
(SFC, 5/5/05, p.A2)
125Mil BC Meat-eating dinosaurs, known as
ceratosaurs, lived in Australia about this time. They represented
globe-trotting groups which spread out across the world before the
continents began to separate. In 2006 a ceratosaur ankle bone was
found near the coastal town of San Remo by an amateur
125Mil BC Eomaia scansoria, a tiny shrewlike
creature, lived in China’s Liaoning province. It was the earliest
known representative of the Eutheria lineage. It’s fossils led
researchers in 2002 to believe that it might be the direct ancestor
of true placental mammals.
(SFC, 4/25/02, p.A2)(SFC, 12/5/02, p.A23)
125Mil BC In 2009 paleontologists reported that a
new dinosaur called Raptorex kriegsteini lived about this time. The
nearly complete fossil had been found in northeastern China. It was
about 9-feet long and weighed about 150 pounds and appeared to be a
miniature prototype of T. Rex, which came some 35 million years
(SFC, 9/18/09, p.A25)
125Mil BC In 2010 British and Chinese scientists
reported that Sinosauropteryx, a squirrel-sized dinosaur from this
period, was covered in complex feathers colored in a subdued palette
of chestnut and white stripes. It was first discovered in China in
1996 in fossil beds dated to 124.6-122 million years ago, during the
late Barremian to early Aptian stages of the Early Cretaceous.
125Mil BC In 2005 Farmers in Inner Mongolia found
a fossil of a small mammal from about this time that displayed
evidence of being able to glide. It was named Volaticotherium
antiquius. Tests for age ranged as far back as 164Mil BC.
(SFC, 12/14/06, p.A15)
125Mil BC - 113 Mil BC The Aptian stage of the
lower Cretaceous. It succeeds the Barremian and precedes the Albian.
125-90Mil BC In 1998 the discovery of the
Suchomimus tenerensis dinosaur was announced by Paul Sereno of the
Univ. of Chicago. It was found in the Tenere Desert of central Niger
where a vast lake was located at this time. The dinosaur was 36 feet
long and stood 12 feet high at the hip.
(SFC, 11/13/98, p.A3)
c124Mil BC A meat-eating dinosaur called
Sinornithosaurus, dated to this time, was found in Liaoning
province, China, around 2002. The skin was covered with fibers but
it had no wings.
(SFC, 7/25/02, p.A3)
124Mil BC - 110Mil BC The fossil of a full-fledged
bird named Jeholornis prima, found in 2002 in Liaoning province,
China, was dated to this time.
(SFC, 7/25/02, p.A3)
120Mil BC In 2007 researchers from Karlsruhe's
Natural History Museum found a 3-millimetre-long (0.118 inch) ant in
the Amazon rainforest and dated its origin back to about this time,
making it the oldest still inhabiting the earth.
120Mil BC Scientists reported in 2008 that a
sparrow-sized pterodactyl, which they named Nemicolopterus
crypticus, inhabited China’s Liaoning province about this time.
(SFC, 2/12/08, p.A5)
120Mil BC A fossil of Protopteryx from this time
in China indicated feathers that were held to have evolved from
(SFC, 12/8/00, p.D4)
120Mil BC Microraptor was one of many small,
feathered dinosaurs, lived in China about this time in time early
120Mil BC A new species of a carnivorous dinosaur
from this time was found in 1997 in southern England. At 26-feet it
was larger than a velociraptor but smaller than a tyrannosaurus rex.
(SFC, 1/24/97, p.A15)
120Mil BC The dinosaur Eotyrannus lengi roamed
Britain. In 2001 a 15-foot skeleton was discovered.
(WSJ, 5/10/01, p.A1)
120Mil BC The middle of what later became the USA
was covered by the Niobrara Sea.
(SFC, 8/10/00, p.A16)
117Mil BC - 116Mil BC The Aptian extinction, an
extinction event of the early Cretaceous Period, dated to about this
time. It has sometimes been termed the mid-Aptian extinction event
as a result.
115Mil BC Dinosaur bones from the Budden Canyon
Formation of western Shasta Ct., Ca., dated to this time of the
Cretaceous. It was a small bipedal herbivore about the size of a
deer. It seemed similar to a group known as hypsilophodonts, small a
primitive members of the suborder Ornithopoda. The region was a
seafloor west of the coastline of this time.
(PacDis, Summer ’97, p.26)
115Mil BC In 2006 scientists identified two
ancient reptiles that swam in icy waters off Australia about this
time. The discoveries, dubbed Umoonasaurus and Opallionectes,
belonged to a group of animals called plesiosaurs, long-necked
marine reptiles that lived during the time of the dinosaurs. Both
creatures lived in a freezing polar sea that covered what is now
Australia, when the continent was located much closer to Antarctica.
115Mil BC In 2007 scientists reported that large,
carnivorous dinosaurs roamed southern Australia about this time,
when the continent was joined to the Antarctica. The 12-foot
dinosaurs were padded with body fat to survive temperatures as low
as minus 30 degrees Celsius. Their findings were based on fossil
115Mil BC - 105Mil BC Dinosaur tracks were made in
Australia during this period when it was connected to Antarctica and
was located much closer to the South Pole, as a part of the
paleogeographic continent of Gondwana. The average temperature of
the area was around 68 degrees Fahrenheit (20 degrees Celsius). In
2011 printed slabs of sandstone were found along the rocky and
remote Milanesia Beach in Otways National Park, west of Melbourne.
113Mil BC A juvenile dinosaur fossil from
Benevento Province in southern Italy was discovered in the 1980s. It
was named Scipionyx samniticus and showed some preservation of soft
parts. [see 110 Mil]
(SFC, 3/26/98, p.A11)
112Mil BC - 99Mil BC Most of Nevada was a flood plain and supported
dinosaurs including the raptor dromaesaur, sauropods,
tyrannosauroids and iguanodonts.
(SFC, 12/2/06, p.A6)
110Mil BC The ancestors of modern elephants began
(SFC, 4/30/98, p.A13)
110Mil BC In 2002 a pterosaur fossil from this
time was discovered in Brazil that indicated it skimmed over water
for food and had a huge bony crest on its head.
(SFC, 7/19/02, p.A5)
110Mil BC The Australia Daintree rain forest of
North Queensland dated to this time.
(SSFC, 6/9/02, p.C7)
110Mil BC In 2006 Chinese researchers reported
nearly complete fossils of Gansus yumenensis, a grebe-like waterbird
from this time, making it the oldest for the group Ornithurae.
110Mil BC The carnivorous dinosaur Microraptor
zhaoianus lived in China about this time along with the fish-eating
bird Yanornis martini. A forged fossil in 1999 linked the 2 as one
(SFC, 12/5/02, p.F2)
110Mil BC In Oklahoma the plant eating
Tenontosaurus roamed the area along with the meat-eating
Deinonychus. Fossils of both together were found in 1999.
(SFC, 2/23/99, p.A4)
110Mil BC Fossils of Sauroposeidon proteles, a
60-ton, 60-foot tall dinosaur, were found in 1994 near Antlers,
(SFC, 11/4/99, p.A8)
110Mil BC An ankylosaur, a plant-eating dinosaur
with powerful limbs, armor plating and a club-like tail inhabited
northern Alberta. Its fossils, discovered in 2011, were not supposed
to be there because the area at this time was covered by water.
110Mil BC Fossils of the Nigersaurus taqueti,
a plant-eating sauropod dinosaur from Niger, was reported in
1999 by a team led by Paul Sereno.
(SFC, 11/12/99, p.A4)
110Mil BC The giant Sarcosuchus imperator,
"flesh-eating crocodile emperor," lived about this time in what
later became the Tenere Desert of Niger.
(SFC, 10/26/01, p.D6)
110Mil BC A well preserved baby fossil of the
therapod Scipionyx from this time was later found in Italy. It was
reported in 1999 to have had a hepatic piston breathing system good
for sustained activity and swift movement. [see 113 Mil]
(SFC, 1/22/99, p.A4)
110Mil BC In 2007 the fossils from Nigersaurus
taqueti, a dinosaur of this time with a strange jaw designed to
hoover-up food grazed in what became the Sahara Desert, went on
display in Washington, DC.
110Mil BC Univ. of Chicago paleontologist Paul
Sereno unearthed Kryptops palaios, a short-snouted, hyena-like
beast, and Eocarcharia dinops, a shark-toothed, bony-browed killer,
during an expedition in the Niger Desert in 2000. The fish-eating,
sail-backed Suchomimus or "crocodile mimic," was found in 1997. The
animals originally lived in the southern landmass that was known as
(Reuters, 2/13/08)(AP, 2/14/08)
110Mil BC - 80Mil BC The Pacific Plate collided with the North
American Plate at the southern end of the Sierra Nevada and in the
process created the Farallon Islands, which then slowly moved north
some 300 miles to stand off the coast of San Francisco.
(SFC, 5/25/13, p.C1)
104Mil BC In 1914 Romanian Baron Franz Nopcsa
(1877-1933) found fossils of small dinosaurs in Romania that dated
to about this time in the Cretaceous period.
(SFC, 6/8/06, p.A7)
100Mil BC No deep ocean floor or volcanic oceanic
islands have yielded rock more than about this age.
100Mil BC Some microbe colonies became locked in
subterranean abodes and separated from the rest of life on Earth
from about this time or earlier. Bacillus infernus was later named
as representative of this group that can tolerate temperatures of
110-185 degrees F.
(SFC, 8/22/97, p.A10)
100Mil BC In 2011 it was reported that the
discovery of a single sauropod vertebra on James Ross Island in
Antarctica reveals that these behemoths, which included Diplodocus,
Brachiosaurus and Apatosaurus, lived on the continent about 100
million years ago.
100Mil BC We can date the salt deposits to this
time and that may have been the time when the sea began to creep in
between the uplands of Africa and those of South America.
100Mil BC Australia split from Gondwana about this
time and began drifting north away from what is now Antarctica,
pushed by the expansion of a rift valley into the eastern Indian
100Mil BC A snake, later named Wonambi, emerged in
Australia about this time. It was believed to have gone extinct
about 50,000 BC.
(SFC, 2/16/06, p.A4)
100Mil BC Pterodaustro, a freshwater pterosaur,
flew over a fresh water lake in what is now a corner of the
Argentine province of San Luis.
(NH, 11/96, p.34)
100Mil BC In 2000 It was reported that researchers
had unearthed a pack of large predatory dinosaurs in Patagonia that
dated back to this time. The fossils were found in Neuquen province
and were named Mapusaurus roseae.
(SFC, 3/11/00, p.A1)(SFC, 4/18/06, p.A3)
100Mil BC The Brazilian state of Ceara was at the
bottom of a vast ocean whose sea floor was rich in phosphates. The
phosphates turned the carcasses of primitive, bony fish to stone in
a matter of days, before the natural decaying process set in.
Calcite nodules are so common in Ceara that they are used to pave
roads. Inside the nodules are some of the best preserved fossils in
(SFME, 5/7/95, P.5)
100Mil BC A cricket-like insect of the genus
Schizodactylus lived in Brazil about this time. In 2011 it was
reported that a contemporary version of the creature had an almost
identical body plan.
(Econ, 2/12/11, p.88)
100Mil BC Researchers estimate that the major
orders of birds and mammals evolved from about this time. They
believe that the breaking up of the ancient continents may have may
have been the major cause.
(SFC, 5/16/96, p.A-7)
100Mil BC A report in Nature Apr 30, 1998, traced
mammals back to around 100 million years using a "molecular clock."
[see 110 million]
(SFC, 4/30/98, p.A1)
100Mil BC Dinosaurs native to Asia traveled about
this time over to North America according to fossil evidence in
(SFC, 4/27/99, p.A2)
100Mil BC Fossils of a predator dinosaur that
lived about this time in Utah were discovered in 2008. Scientists in
2013 named it Siats meekerorum, and said it was related to
(SFC, 11/23/13, p.A10)
100Mil BC Spinosaurus, a 55 foot, 8 ton dinosaur
with crocodile-like jaws lived during this time in Argentina,
Morocco, Tunisia, Algeria.
100Mil BC Africa became geographically isolated
about 100 million years ago.
(SFC, 5/17/96, p.A-3)
100Mil BC Land masses collided about this time and
(SFC, 4/27/99, p.A2)
100Mil BC The oldest known penis is about 100
million years old. It belongs to an ostracod, an early crustacean
related to crabs, shrimps and water fleas, and was found in a fossil
sample unearthed in Brazil.
100Mil BC About this time a cluster of stars
crashed into a larger cluster at about 5k km. per second. This was
later considered as the highest energy cosmic event since the Big
Bang. Winds generated by the collision created a bullet-shaped cloud
of hot gas later named 1E0657-556 (the bullet cluster).
(Econ, 8/26/06, p.65)
100Mil BC In 2008 astronomers witnessed the start
of an explosion of a star, about the same size in diameter as the
sun, that was only about 10 million years old. The supernova in
galaxy NGC2770 was about 100 million lights years distant. The
observation was made while observing another star well into its
100Mil BC - 84Mil BC During this period of the
Cretaceous temperatures rose to 38 degrees in the tropical waters
off Suriname, compare to 26-28 degrees in 2006.
(Econ, 2/25/06, p.82)
100Mil BC - 65Mil BC Late Cretaceous granites
provided the gold of the Mother Lode quartz veins. Erosion of these
granites released the mineral orthoclase and orthoclase-rich
sediments and may be observed today in roadcuts along California
Highway 128 about 2.8 miles southwest of Monticello Dam on Lake
99Mil BC-96 Mil BC A saber-toothed, squirrel-like
creature lived about this time. Fossils of the animal, named
Cronopio dentiacutus, were discovered in 2011 in the Rio Negro
region of Argentina.
98.4Mil BC In 1999 it was reported that ankylosaur
dinosaur (fused lizards) fossils from this time were found in Utah.
Fossils of the nodosaur, a primitive ankylosaur lacking a tail club,
were also found.
(SFC, 4/27/99, p.A2)
98Mil BC In Utah volcanic ash just above a large
deposit of fossils was dated to this time.
(SFC, 10/14/97, p.A9)
97Mil BC - 94Mil BC A giant dinosaur lived in Patagonia about this
time. Its first fossils were found in 1987 and later named
Argentinosaurus. It is among the largest known dinosaurs.
95Mil BC Gigantosaurus, a 47 foot, 8 ton dinosaur
with 8-inch-long serrated teeth lived during this time in Argentina.
95Mil BC About this time birds that were the
ancestor of modern birds, evolved an improved sense of smell. In
2011 studies used fossils of Bambiraptor to determine that birds
inherited a good sense of smell from dinosaurs, and then improved
the faculty. Bambiraptor, dating to this time, was a fast-moving,
non-flying critter about the size of a dog.
95Mil BC A dinosaur fossil named Rugops primus
(first wrinkle face), unearthed in Niger in 2000, dated to this
time. It belonged to a group of southern dinosaurs called
abelisaurids, also found in South America, Madagascar and India and
indicated the Africa was still connected to Gondwana at this time.
95Mil BC Fossils of Carcharodontosaurus
iguidensis, a meat-eating dinosaur from this time, was first found
in Morocco in the 1920s. Better fossils were found in Niger in 1997.
The upright-walking creature grinned with a mouth full of
banana-sized teeth, stood taller than a double-decker bus and
weighed more than two standard-sized cars. "It seems that shallow
seas divided Morocco and Niger, promoting evolutionary separation of
the species living in the two regions."
95Mil BC The 3-foot-long snake Pachyrhachis
problematicus lived in a shallow sea over Israel about this time. It
had short, well-developed hind limbs and may have been related to
mosasaurs, giant swimming reptiles.
(SFC, 4/16/97, p.C14)
94Mil BC Amber of this age has been found in the
Atlantic Coastal Plain of New Jersey.
(PacDis, Winter/’97, p.13)
94Mil BC In 2001 fossils of a large sauropod were
discovered in Egypt near the remote Bahariya oasis. A Univ. of
Pennsylvania team named it Paralititan stromeri (tidal giant of
Stromer) after a German scientist who had studied the area.
(SFC, 6/1/01, p.A1)
93Mil BC A therizinosaur dinosaur, dubbed
Nothronychus graffami, lived about this time. Fossils of the
pot-bellied dinosaur were discovered in southern Utah. When alive,
the animal would have stood at 13 feet (4 meters) and sported a
beaked mouth and forelimbs tipped with 9 inch- (22 cm)-long sickle
93Mil BC From cliffs in the region Kem at the edge
of the Sahara in Morocco, paleontologist Paul C. Sereno and team
unearthed a 5-foot-4-inch skull of Carcharodontosuarus saharicus and
much of the skeleton. Previous fragments of this dinosaur had been
unearthed 50 years ago by German researchers, but the bones were
destroyed during World War II. Also found was the previously unknown
species of smaller carnivore they named Deltadromeus agilis (agile
delta runner). It was 27 feet long and would have weighed 3-4 tons.
(SFC, 5/17/96, p.A-3)
92Mil BC The New Jersey region was a moist,
coastal area of swamps, lagoons and cedar forests. In 1998 a 170
pound piece of amber was found with hundreds of various insect
species embedded that included ants with a distinct metapleural
gland that secreted acid for killing fungi and bacteria.
(SFC, 1/29/98, p.A2)
90Mil BC The ancestors of modern horses began
(SFC, 4/30/98, p.A13)
90Mil BC Scientists in 2011 reported the discovery
a previously unknown, plant-eating dinosaur in Angola that dated to
about this time. It was named Angolatitan adamastor. The fossil was
found along with fish and shark teeth in what would have been a sea
bed 90 million years ago.
(SFC, 3/17/11, p.A2)(http://tinyurl.com/4k4vtum)
90Mil BC Mudstone of this age from Plaza Huincul
in Patagonia revealed fossil pieces in 1996 of the huge Megaraptor.
(NG, 12/97, p.134)
90Mil BC Scientists in 2005 announced the
discovery in Argentina of a rooster-size fossil named Buitreraptor
gonzalezorum. It dates back 90 million years and closely resembles
fossils from the North. It was part of the class called dromaesaurs
believed to have originated 180 million years ago in Laurasia. The
new find was evidence that dromaesaurs originated in Pangea, before
it broke apart to form Laurasia and Gondwanaland.
90Mil BC The Baurusuchus salgadoensis lived in an
area of southeastern Brazil known as the Bauru Basin, some 700
kilometers (450 miles) west of modern-day Rio de Janeiro. The
fossilized skeletons appear to be closely related to another ancient
crocodile species, the Pabwehshi pakistanesis discovered in
90Mil BC The fossil of a snake that lived in
Patagonia at this time was found in 2006 with 2 small rear legs. The
snake, under 3 feet long, was named Najash rionegrina.
(SFC, 4/20/06, p.A2)
90Mil BC In 2001 Paul Sereno, a paleontologist,
helped lead an expedition to China that uncovered the fossilized
remains of the 25 young sinornithomimus near Suhongtu, a tiny,
remote village in the Gobi desert about 370 miles (600 kilometers)
west of Hohhot.
90Mil BC - 89Mil BC The granite of Montara
Mountain on the San Francisco peninsula and the granite of the
Farallon Islands have been shown by radioactive potassium dating to
be about 90 million years old.
(GH-ADH, p.20)(SSFC, 7/3/05, p.E3)
90Mil BC - 70Mil BC Paleontologists in 1997 found
an area in Patagonia, Arg., over a mile square that was once a
dinosaur nesting site of this period. Fossilized embryos revealed a
delicate skin of reptilian scales.
(SFC, 11/18/98, p.A4)
88Mil BC In 2000 Scientists in Argentina began
uncovering the skeleton of what is believed to be a new dinosaur
species, a 105-foot plant-eater that is among the largest dinosaurs
ever found, has been uncovered in Argentina. They named it
Futalognkosaurus dukei after the Mapuche Indian words for "giant"
and "chief," and for Duke Energy Argentina, which helped fund the
skeleton's excavation. The skeleton dated to 88 million years BC.
98Mil BC Scientists in 2009 confirmed for the
first time that Australia was once home to a dinosaur of this time
that was big, fast and terrifying. Australovenator wintonensis was a
1,100 pound (500 kilogram) meat-eating predator with three slashing
85Mil BC Tylosaurus, a predatory marine lizard, on
exhibit at the American Museum of Natural History.
(NH, 6/96, p.33)
85Mil BC The ancestors of modern cows began
(SFC, 4/30/98, p.A13)
85Mil BC In 2005 Chinese researchers discovered a
bird-like dinosaur that lived about this time. The feathered but
flightless Gigantoraptor erlianensis weighed about 1.4 tons and had
a beak but no teeth.
85Mil BC - 70Mil BC Canadian scientists in 2011
reported the discovery of 11 feathers preserved in amber that dated
to about this time.
(Econ, 9/17/11, p.88)
85Mil BC - 65Mil BC California dinosaur fossils of
the Cretaceous have been found in the Moreno and upper Panoche
Formations of western Fresno Ct., the Point Loma Formation near San
Diego, and the Ladd and Williams Formations of Riverside Ct. These
include the Saurolophus, a large bipedal "duckbill" dinosaur.
(PacDis, Summer ’97, p.28)
c84Mil BC Garnet-rich crustal rock called eclogite
formed below an area that later became the Sierra Nevada of
(SFC, 7/30/04, p.A4)
84Bil BC - 66Bil BC An 85-foot-long dinosaur lived during this
period in a region later known as Patagonia, Argentina. Fossils of
the dinosaur were discovered in 2005. In 2014 the giant and a
smaller speciman were dubbed Dreadnoughtus schrani, after a
battleship and Adam Schram, an entrepreneur who financed the
(SFC, 9/5/14, p.A7)
84Mil BC - 82Mil BC In 2000 scientists reported
that the Earth tilted as much as 16-21 degrees over this period when
vast chunks of crust dove deep into the viscous mantle.
(SFC, 1/21/00, p.A3)
80Mil BC Scientists in 2005 reported that,
titanosaurian suaropods, plant eaters from this time, dined on a
variety of grasses previously believed to have evolved 10 million
years after dinosaurs disappeared.
(SFC, 11/18/05, p.A4)
80Mil BC Dinosaurs roamed the Sierra foothills. A
therapod bone fossil was found in Placer Ct. in 1997, in a
geological region called the Chico formation. Here sediment was laid
down by the Pacific Ocean whose tides washed the cliffs of the
(SFC, 6/20/97, p.A1)
80Mil BC Upper Cretaceous terrestrial siltstones
and sandstones in Big Bend National park, Texas, has fossil of
Quetzalcoatlus. It is the largest known Pterosaur with a wingspan of
12 m. It was probably a scavenger and was covered with hair.
80Mil BC Upper Cretaceous Judith River and Two
Medicine Formations in Montana have fossils of Palaeoscincus. It was
squat, tank-like, with heavy armor over the back and spikes
projecting from the sides. It was 5m long, broad and sprawling. It
belongs to the group Ankylosauria, one of the four sub-orders of
Ornithiscia. Two other were Silvisaurus and Scolosaurus.
80Mil BC Upper Cretaceous Hell Creek Formation in
Montana has fossils of Tyrannosaurus. It stood 12m and could only
take short steps due to its leg joint and foot structure. It had
15cm long teeth that were saw edged, thin, and easily broken. All
this indicates that it was most likely a scavenger. Its skull was
loose jointed and it could dislocate its jaws like a snake and gulp
down great chunks of meat. In 2002 computer modeling limited its
speed to 25 mph at most.
(TE-JB, p.89)(WSJ, 2/28/02, p.A1)
80Mil BC Upper Cretaceous Lance Formation in
Montana, Wyoming and S. Dakota has fossils of Pachycephalosaurus
(thick-headed lizards). They stood on two feet and were herbivorous.
They had a dome-like development on the skull made of solid bone,
most likely used in combat as a battering ram. It stood 5m and had
spikes on its nose and around the back of its skull.
(TE-JB, p.91)(Econ, 10/27/12, p.81)
80Mil BC Hadrosaurs such as Brachylophosaurus
Canadensis lived in Montana. Biochemical evidence from a fossilized
femur later suggested an evolutionary link of such duck-billed
dinosaurs to birds.
(SFC, 5/5/09, p.A8)
80Mil BC Upper Cretaceous Lance Formation in
Wyoming, Colorado, Montana and Saskatchewan has fossils of
Triceratops. It was the largest and one of the last of the
ceratopsians. it had three long horns on its head and a solid bone
shield that swept backwards over its shoulders. They were
plant-eaters with hooked beaks.
80Mil BC A Cretaceous era creature known as the
maiasaur roamed what is today the northern United States. Multimedia
simulations by the Royal Ontario Museum have brought the creature
back to life.
(Wired, Dec. '95, p.58)
80Mil BC In 2013 scientists in Utah unveiled the
bones of a dinosaur discovered in 2009. It was named Lythronax
argestes, or "king of gore," for its large teeth and apparent
dominance as a predator. They dated it to about 80 million BC.
80Mil BC Fossil eggs and embryos of titanosaurs
and apatosaurus of this age were later found in the Patagonian
badlands of Argentina.
(SFC, 9/28/01, p.D8)
80Mil BC A land-bound reptile, described as a
possible link between prehistoric and modern-day crocodiles, roamed
arid and hot terrain that became Brazilian countryside about this
time. A fossil of Montealtosuchus arrudacamposi was found in 2004
and displayed in 2008.
80Mil BC Upper Cretaceous Oldman and Edmonton
formation in Alberta, Canada, has fossils of Struthiomimus. It was
typical of the "ostrich dinosaurs," the last of the coelurosaurs.
Their forelegs had three-fingered grasping hands. The body was long,
horizontal, and balanced by a long rigid tail.
80Mil BC Upper Cretaceous Oldman Formation at Red
deer River, Alberta, Canada, has fossils of the crested duck-billed
Lambeosaurus. It had a massive array of grinding teeth, strong hind
legs with three toes tipped with hoofs and stood 7 m. The smaller
front legs had four toes, two of which had hoofs. There were webs
between the fingers and its tail was flattened from side to side.
Other crested, duck-billed dinosaurs include Corythosaurus,
Saurolophus, and Parasaurolophus. Nests of Maiasaura discovered in
Montana in 1979 have a number of young an advanced stage of
development that indicate adult supervision of the young.
80Mil BC Upper Cretaceous Bahairia Formation in
Egypt and Niger have fossils of Spinosaurus. It had fins on its back
supported by strong spines projecting up from the vertebrae. It was
the largest of the fin-backed dinosaurs and the spines were about
1.8 m long.
80Mil BC Caverns at the Grutas de Cacahuamilpa
National Park south of Mexico City date to this time.
80Mil BC An eighty million-year-old egg was found
in Mongolia’s Gobi desert by paleontologists who claim it is the
first embryo ever found of a meat-eating dinosaur called oviraptor.
A report on the discovery appears today in the journal Science.
(WSJ, 11/4/94, p.1)(SFC, 2/14/02, p.A6)
80Mil BC Bones from a velociraptor in Mongolia’s
Gobi desert indicated that the dinosaur had a wishbone. The
wishbone, fused collarbones, later provided attachment points for
muscles that allow birds to fly. Also found was a placental mammal
with epipubic bones, structures that had been only associated with
marsupials and monotremes. In 2007 scientists reported evidence of
feathers on the velociraptor uncovered in 1998.
(SFEC, 10/5/97, p.A20)(Reuters, 9/20/07)
80Mil BC The Ukhaa Tolgod basin of Mongolia had
fossils from the late Cretaceous. The site was first discovered by
Roy Chapman Andrews during his 1923 Gobi Desert expedition. The
25-foot tall, 85-foot long Nurosaurus qaganesis was of this period.
(THM, 4/27/97, p.L4)
80Mil BC The fossil record later indicated that
palms have been around since at least this time.
(SFC, 11/14/07, p.G2)
80Mil BC - 75Mil BC In Utah rocks dating to this
period contained burrows fossilized in sandstone. Scientists in 2010
speculated that signs of digging around the burrows were evidence of
dinosaurs digging for small mammals.
(Econ, 7/31/10, p.66)
80Mil BC - 70Mil BC Late Cretaceous to Early
80Mil BC - 70Mil BC The Laramide orogeny of the
late Cretaceous was largely responsible for the major features in
the structure of the Western Cordillera.
80Mil BC - 70Mil BC The north-west
states of Washington, Idaho and Oregon at
this stage became the site of a flood of basalt lavas from many
local fissures. By the time it was over, some 1500 meters of lava
flows had accumulated, covering about 512,000 sq. km.
80Mil BC - 70Mil BC It might be said that for
South America the orogenic crunch came in the late Cretaceous. At
that time the giant bathyliths of the Andes were intruded and the
whole region was raised.
80Mil BC - 70Mil BC Only one family of flowering
plants is known from the earliest late Cretaceous, but by the end of
that period at least 67 families existed.
80Mil BC - 70Mil BC South-west of Delhi and
covering much of the north-western half of the Indian shield are
thousands of square kilometers of flat-lying floods of late
Cretaceous and early Cainozoic basalt, the Deccan traps.
80Mil BC - 70Mil BC During India’s passage
northward its western margin seems to have crossed a hot spot on the
crust. This resulted in the release of floods of basalt over the
western part of the subcontinent.
80Mil BC - 70Mil BC The Mesozoic era closed with
the continents apparently emerging from the waters once again.
80Mil BC - 70Mil BC To what extent climactic
change set off the train of extinctions at the close of the Mesozoic
era is uncertain. The cycads and about half the species of early
flowering plants died out and the conifers began to extend their
realm little by little from the cooler areas. Floating,
single-celled, algal plants became very abundant and secreted the
minute limey platelets, known as coccoliths, which built up as
chalk. Their photosynthetic activity may have tilted the abundance
of the atmosphere in favor of oxygen and depleting it of carbon
dioxide generating a reverse "greenhouse effect."
80Mil BC - 70Mil BC Among the typically Paleozoic
groups to fade away at the end of the Mesozoic were certain large
protozoans or foraminifera, the trilobites, the strange segmented
eurypterids, the rugose corals, many bryozoa, echinoderms and
80Mil BC - 70Mil BC By the end of the Mesozoic the
ammonites became extinct and only a few species of their hardy but
possibly more primitive relatives, the nautiloids, survived.
80Mil BC - 70Mil BC The squid-like belemnites
together with some families of bryozoa, echinoids and floating
foraminifera all disappeared.
80Mil BC - 70Mil BC A dinosaur the size of a
gigantic turkey lived in Europe during the late Cretaceous. In 2010
Romanian fossil hunters unearthed the remains of the velociraptor
and named it Balaur Bondoc (stocky dragon). Europe at this time was
an archipelago of islands.
(SFC, 8/31/10, p.A4)
78Mil BC Fossil bones of a plesiosaur that lived
about this time were unearthed at a Kansas ranch in 1968. The
15-foot dinosaur was believed to have given birth to live young
78Mil BC A dinosaur species of this time, later
found in Canada and named Albertaceratops nesmoi, was a plant-eater
with yard-long horns over its eyebrows, suggesting an evolutionary
middle step between older dinosaurs with even larger horns and the
small-horned creatures that followed.
77Mil BC In 2005 it was reported that
paleontologists had identified a new dinosaur species, an early
relative of Tyrannosaurus rex that roamed what is now the
Southeastern US about this time. The scientists made the
identification from hundreds of fossilized fragments collected
mostly in Montgomery County, Ala., and southwestern Georgia. They
named the new dinosaur Appalachiosaurus montgomeriensis, which means
"the Appalachian lizard from Montgomery County." The 25-foot-long
creature roamed the earth 10 million years before T. rex and was
smaller and more primitive, with a narrower snout.
76Mil BC The Point Loma Formation near Carlsbad,
CA., contained a nodosaurid, a quadrupedal herbivorous dinosaur with
an extensive covering of bony armor.
(PacDis, Summer ’97, p.30)
76Mil BC The horned dinosaur Spinops
sternbergorum, which comes from the same herbivore family as the
Triceratops, lived about this time. It remains were discovered in
1916 in a quarry known as the "bone bed" in Alberta, Canada. In 2011
scientists identified the bull-size dinosaur as a new species of the
76Mil BC The 15-foot dinosaur Nasutoceratops
titusi lived about this time. Fossils of the 2.5 ton big-nosed,
horned-faced dinosour were discovered in Utah in 2013.
(SFC, 7/18/13, p.A6)
75Mil BC The Birthday Site of northwestern Montana
features 3 types of hadrosaurs: the Prosaurolophus, the Gryposaurus,
and the Hypacrosaurus. The Daspletosaurus (a 30-foot carnivorous
dinosaur) and the human sized Troodon were also here. The site was
shallow lake water and the array of bones indicates some type of
(NH, 4/97, p.66)
75Mil BC In 1994 the fossil of a birdlike dinosaur
was found in Montana. It was about 3 feet long and weighed about 7
pounds. It was named Bambiraptor feinbergi.
(SFC, 3/18/00, p.A10)
75Mil BC The ornithominids of this time were
long-necked, birdlike dinosaurs that evolved beaks with comb-like
structures to strain nutrients from water.
(SFC, 8/30/01, p.A4)
75Mil BC The 30-foot dinosaur Majungatholus atopus
lived in Madagascar about this time. It was similar to creatures
whose fossils were found in Argentina and India. The horned dinosaur
was a remote cousin of T. rex and had sharp serrated teeth. In 2003
scientists determined that 2-ton, 30-foot creatures were cannibals.
(SFC, 5/15/98, p.A2)(SFC, 4/3/03, p.A2)
75Mil BC - 71Mil BC Fossils from Ukhaa
Tolgod, Mongolia, of this period later provided the richest
assemblage of vertebrates in the world.
(NH, 7/00, p.51)
75Mil BC - 50Mil BC Teleost diversity exploded
over this period.
(NH, 6/96, p.37)
74Mil BC In the Manson Impact a meteorite hit what
is now Manson Iowa at an estimated 60,000 mph and formed a crater 24
miles wide with an impact 3 1/2 miles deep.
(SFEC, 7/5/98, p.A10)
72Mil BC A helmet-crested, duck-billed dinosaur
lived about this time in northeastern Mexico. In 2008 the species
was named Velafrons coahuilensis.
71Mil BC The Earth's continents were clustered
together and sea level was much higher. The Atlantic Ocean was
small, the Pacific was enormous and covered half the Earth. The
Tethys Sea, a shallow, salty body of warm water separated the
northern and southern hemispheres. Enriquetta Barrera, using
evidence from one-celled foraminifera, has found indications of a
gradual high-latitude cooling and a rapid and sharp decrease in deep
ocean temperatures in conjunction with a 150 foot drop in sea level.
This lasted about a million years, when sea levels went back up.
(MT, Dec. '95, p.7)
Go to 70 Mil BP