Geological Time & Paleobiology

Fossil Mall
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Chart of Geological Time:
Denoting Significant Events in:
Evolution, the Fossil Record,
Paleontology and Paleobiology
"visit links for more information"

 

 

 

 

 




 

 

 

 

 

 

 

 

 

 

Phanerozoic EON
(544 mya to present)

"The age of visible life"

ERA
Periods
EPOCH
Evolutionary Milestones

Cenozoic Era
(65 mya to today)

Quaternary (1.8 mya to today)

Holocene (11,000 years to today) Last major ice age ends. Modern man migrates to the Americas.
Pleistocene (1.8 mya to 11,000 yrs) Neandertals appear and disappear; Homo erectus and Homo sapiens appear.
Tertiary (65 to 1.8 mya)Pliocene (5 to 1.8 mya) Ape-like ancestors of modern humans (Hominids); the Australopithecines appear and disappear. Homo habilis lives from 2.5 to 1.8 mya.
Miocene (23 to 5 mya)Grazing horses, antelopes appear
Oligocene (38 to 23 mya)

Radiation of more modern animals: most modern bird forms have appeared; most modern mammals have appeared.

Eocene (54 to 37 mya)First grasses appear, a resource for herbovores; trees thrive. Some modern mammals appear: advanced primates; camels, cats, dogs, horses & rodents
Paleocene (65 to 54 mya)Flowering plants begin radiation extending through the Eocene. Small mammals radiate
Mesozoic Era
(245 to 65 mya)

Cretaceous (146 to 65 mya)

Divided
as:

Upper;

Middle;

Lower

Major extinction includes dinosaurs and ammonites (K-T)
Appearances include: flowering plants(angiosperms); lizards; placental animals (early mammals); snakes; social insects; marsupial and primitive placental animals
Modern insect forms radiate

Jurassic (208 to 146 mya) Appearances include birds; crabs; frogs and salamanders
Dinosaurs radiate to dominate the land
Triassic (245 to 208 mya) Breakup of Pangaea begins
Major extinction event: tabulate corals and conodonts disappear - ammonites, reptiles and amphibians decimated
Appearances include: dinosaurs; crocodiles; marine reptiles; turtles;
Pterosauria and mammals
Major groups of seed plants appear

 

Paleozoic Era
(544 to 245 mya)

Permian (286 to 245 mya)

Major extinction of invertebrates (P-T). Trilobites fade away forever. All but articulate crinoids dissapear
Seedplants producing large trees

Carboniferous
(360 to 286 mya)
Pennsylvanian (325 to 286 mya) Conifers & many winged insects appear
Mississippian (360 to 325 mya) Reptiles appear. Trilobites become scarce
Devonian (410 to 360 mya)Mass extinction (F-F)
Land colonized by plants and animals
Appearances include: insects; sharks; amphibians (tetrapods); lung fishes and earliest seed plants.
Extensive radiation of fishes.
Silurian (440 to 410 mya)Jawed fish, cartilaginous fish and vascular plants appear. Primitive terrestrial predators: Arachnids.
Ordovician (500 to 440 mya)
Mass extinction
First land plants; bryozoans appear. Trilobites begin to specialize.
Cambrian (544 to 500 mya)Tommotian (530 to 527 mya)Appearance of hard parts and vision - fossils become common. Appearances include: vertebrates; jawless fish; small shelly animals; conodonts; trilobites radiate repeatedly and reach their peak diversity.First major radiation of animals

 

Precambrian Time
(4,500 to 544 mya)

"deep time on earth"

Proterozoic Era
(2500 to 544 mya)
Vendian (650 to 544 mya) or Ediacaran
No Epochs

Extinction at end of Vendian
Macroscopic, soft-bodied organisms radiating.

Oldest metazoans (multicellular animals) - Ediacaran Fauna.

Neoproterozoic (900 to 544 mya) - Late

Macroscopic fossils of soft-bodied organisms.
Chloroblasts arise from cyanobacteria through endosymbiosis.

Stromatolite diminishing.

Mesoproterozoic (1600 to 900 mya) - MiddleSexual reproduction appears (about 1 billion years ago)
First land fungi
Paleoproterozoic (2500 to 1600 mya) - EarlyMore complex single-celled life with aerobic metabolism begin diversification
Rusting of earth, depletion of oceanic Fe in banded iron formations
Peak of stromatolite with cyanobacteria oxygenating the atmosphere

Archaean
(3800 to 2500 mya)

Primitive Eukarya appear
Photosynthesis appears
Oldest fossils - Apex Chert of Australia (3.55 BYA) - Prokaryotes dominate (Eubacteria and Archaea); simple cell forms form stromatolite

First life appears - Heterotrophic, anerobic, Asexual
Oldest sedimentary rocks (3.8 BYA)

Hadean
(4500 to 3800 mya)
Earth's environment extremely hostile to life as we know it