P
H
A
N
E
R
O
Z
O
I
C
E
O
N
|
Paleozoic Era
540-245 MYA
|
Cambrian Period
540-505 MYA
|
Mild climate; extensive seas, spilling over continents.
Shelled marine invertebrates.
Explosive diversification of eukaryotic organisms.
swimming, floating, crawling, clinging, burrowing sea animals.
Trilobites, brachiopods, radiolarians, sponges, echinoderms,starfish, seacucumbers, jellyfish, worms, eurypterids (water scorpions).
Plants only as algae.
|
|
Ordovician Period
505-438 MYA
|
Mild climate.
Shallow seas; retreating from land and spreading back; teeming with life.
continents low; sea covers US.
Limestone deposits.
All plants and animals still restricted to the water.
Agnatha (jawless fishes, first vertebrates).
First primitive fishes (ostracoderms, vertebrates).
Invertebrates dominant.
Crustaceans, trilobites, graptolites, brachiopods, bryozoa, echinoderms, corals, mollusks, cephalopods.
First fungi.
Possible invasions of land by plants.
|
|
438 MYA
|
Mass extinctions
|
|
Silurian Period
438-408 MYA
|
Mild climate.
Continents generally flat; again flooded.
Mountain building in Europe.
Rise of fishes (placoderms) and reef building corals.
Shell-forming sea animals abundant.
Sea lilies (stalked crinoids), eurypterids, land scorpions.
Invasion of land by arthropods.
Earliest vascular plants (psilopsids, lycophytes).
Modern groups of algae and fungi.
|
|
Devonian Period
408-360 MYA
|
Violent change in Terra's landscape by volcanic activity and crustal movements, folding and mountain forming.
Europe mountainous with arid basins.
Mountains and volcanoes in eastern US and Canada.
Rest of north America low and flat.
Sea covers most of land.
Climate became drier.
Age of fishes.
Sharks, rays.
Fishes move into the open seas.
Lunged fishes (paddle-fins).
Amphibians appear.
Mollusks abundant. Extinction of primitive vascular plants.
Origin of modern groups of vascular plants with true leaves, roots and stems (liverworts).
Terra started to look green.
Some plants started to produce seeds, rather than spores.
|
|
367 MYA
|
Mass extinctions
|
|
Carboniferous Period
360-286 MYA
|
Slower Terran movements.
Seabeds began to rise.
Climate warm; conditions like those in subtropical zones; little seasonal variation, water plentiful.
Lands low, covered by shallow seas or great coal swamps.
Mountain building in eastern US, Texas, Colorado.
Age of amphibians.
First reptiles, cotylosaurs.
Variety of insects.
Sharks abundant.
Greatswamps; forests of ferns, gymnosperms (naked seed plants) and horsetails.
|
|
Permian Period
286-245 MYA
|
Extremely violent climate changes: deserts, swamps, ice.
Extensive glaciation in Southern Hemisphere.
Seas drain from land; worldwide aridity.
Urals formed.
Appalachians formed by end of Paleozoic.
Large amphibians.
Reptiles diversify.
Bugs and beetles (metamorphosis).
Age of the seed plants.
Origin of conifers, cycads and ginkgos; possible origin of flowering plants; earlier forest types wane.
At end of period extinctions of many groups: trilobites, eurypterids, many kinds of corals, bryozoa, sea lilies, brachiopods.
Early fishes (placoderms) and many kinds of shark disappeared.
|
|
|
Mesozoic Era
245-66.4 MYA
|
248 MYA
|
Mass extinctions
|
|
Triassic Period
245-208 MYA
|
At first, deserts stretched out over most of the land, slowly giving way to a mild, moist climate with great areas of forested plains.
Continents mountainous and joined in one mass.
Large areas arid.
Eruptions in eastern North America.
Appalachians uplifted and broken into basins.
The age of dinosaurs, on land, in the sea and in between.
Amphibians in freshwater, retreating.
Primitive mammals appear.
Forests of gymnosperms and ferns.
|
|
208 MYA
|
Mass extinctions
|
|
Jurassic Period
208-144 MYA
|
Warm climate without significant seasonal changes.
Continents low, with large areas covered by seas.
Mountains rise from Alaska to Mexico.
Oxygen levels 50% higher than present day, allowing sauropods to reach their largest sizes.
Dinosaurs' zenith overall.
Flying reptiles, small mammals and birds appear.
Many ammonites and other mollusks dominate the sea.
Gymnosperms, especially cycads and ferns.
First flowering plants (angiosperms).
|
|
Cretaceous Period
144-66.4 MYA
|
Tropical to subtropical climate.
Elevation of Rocky Mountains at end of period.
Africa and South America separate.
In warm, shallow seas, vast layers of chalk laid down by marine organisms.
Birds well developed.
Marsupials, insectivores and flowering plants become abundant.
At end of period extinction of dinosaurs, belemnites, ammonites and most cycads.
Fish survived, mammals and some reptiles.
Angiosperms dominate the land flora, colonize most land and diversify as global temperatures cool.
Ice caps begin to form as the Cretaceous comes to a close, and temperatures drop below
40° C
for extended periods for the first time in millions of years.
|
|
|
Cenozoic Era
65MYA to present
|
Tertiary Period
66.4-1.6 MYA
|
Paleogene
65-25 MYA
|
65 MYA
|
Mass extinctions
|
|
Paleocene Epoch
65-55 MYA
|
Mild to cool climate.
Wide, shallow continental seas largely disappear.First known primitive primates and mammal carnivores.
|
|
Eocene Epoch
55-38 MYA
|
Mild to very tropical climate.
Many lakes in western North America.
Australia separates from Antarctica; India collides with Asia.
Primitive horses, tiny camels, marsupials; modern and giant types of bird.
Most groups now well formed; barnacles, oysters, cuttlefish, crabs, sponges, freshwater snails.
Formation of grasslands.
|
|
Oligocene Epoch
38-25 MYA
|
Rise of Alps and Himalayas.
Lands generally low.
Volcanoes in Rocky Mountains.
South America separates from Antarctica.
Forests decline to make way for grasslands.
Large browsing animals; monkey-like primates appear.
Fish: eel, barracuda, seahorse, cod, trout.
Reptiles: turtles, tortoises, lizards, snakes, crocodiles.
Birds: flightless and flying.
Origin of many modern families of flowering plants.
|
|
|
Neogene
25-2 MYA
|
Miocene Epoch
25-5 MYA
|
Moderate climate; extensive glaciation begins again in Southern Hemisphere.
Moderate uplift of Rocky Mountains.
Whales, apes, grazing mammals.
Spread of grasslands as forests contract.
|
|
Pliocene Epoch
5-2 MYA
|
Cooler climate; continued uplift and mountain building, with widespread glaciation in Northern Hemisphere.
Uplift of Panama joins North and South America.Large carnivores.
First known appearance of hominids (humanlike primates)
|
|
|
|
Quaternary Period
1.6MYA to present
|
Pleistocene Epoch
1.6-0.01 MYA
|
Climate fluctuating cold to mild .
The era of ice ages.
Numerous glacial advances and retreats; fiords formed.
Uplift of the Sierra Nevada; deserts on large scale; Sahara formed.
Ten major ice ages of 100ky each between 1MYA and 100KYA.
Last ice age from 100KYA to 10KYA.
Planetary spread of Homo Sapiens over Eurasia; extinction of many species due to the ice ages; extinction of many large mammals and birds due to humans.
|
|
Holocene Epoch
10KYA to present
|
The last major ice age ends and the sea level rises by 80-110m worldwide, causing new continental margins, dunes and beaches.
Climate still fluctuates in ten little ice ages.
Humans spread across America and all islands.
Major extinctions of large animals and birds due to humans.
|
|
AD 1350-1800 Little Ice Age.
since then a warming trend.
Major habitat changes and deforestations caused by humans.
A major extinction wave due to introduced pests and habitat destruction.
|
|
|
|
|
|