Geologic Periods

Hadean Eon

Spanned from 4.6 BYA to 4.0 BYA.

Eukaryotic Cells Origin

Eukaryotic cells originated around 2.1 BYA.

Devonian Period

Occurred from 416 to 359 MYA.

Cretaceous Period

Spanned from 145.5 to 65.5 MYA.

Atmospheric Oxygen Rise

Caused by photosynthesis by bacteria at the beginning of the Proterozoic Eon.

Stromatolites

First evidence of life appeared in the form of stromatolites around 3.5 BYA.

Paleozoic Era Span

Spanned from 542 to 251 MYA.

Hadean Surface

Characterized by a hot, molten surface.

Archean Eon Span

Spanned from 4.0 BYA to 2.4 BYA.

Hadean Surface Characterization

Characterized by asteroid impacts and volcanoes.

Origin of Life

Likely occurred around 3.9 BYA.

Proterozoic Eon Span

Spanned from 2.5 BYA to 542 MYA.

Ediacaran Fauna Period

Period during which multicellular eukaryotes rose.

Ediacaran Fauna Organisms

Characterized by jellies, anemones, and sponges.

What type or organisms rose during Ediacaran Fauna

Composed of soft-bodied organisms.

Cambrian Period

Occurred from 542 to 488 MYA.

Phanerozoic Eon Fraction

Represents around a ninth of Earth's history.

Span of the Phanerozoic Eon

Began 542 MYA and continues to the present.

Phanerozoic Eon Significance

Notable for most of the history of multicellular organisms.

Cambrian Explosion

Major event associated with a huge increase in diversity and disparity.

Cenozoic Era Periods

Includes Paleogene, Neogene, and Quaternary periods.

Cambrian Explosion Effects

Resulted in a huge increase in diversity and disparity.

Animal Phyla in Cambrian Period

Every extant phylum and some extinct were present.

Cambrian Explosion Contributors

Increased oxygen, bilateral symmetry, hard body structures.

Diversity in Ecology

Refers to the number of species on Earth.

Burgess Shale

Known for Cambrian animals.

Disparity in Ecology

Refers to the variety of body plans.

Silurian Period

Occurred from 444 to 416 MYA.

Ordovician Period

Occurred from 488 to 444 MYA.

Ordovician Fishes

Characterized by Ostracoderms, or armored jawless fishes.

Ordovician Period Abundance

Lots of trilobites were abundant.

Devonian Period Fishes

Characterized by Placoderms, or armored fishes.

Silurian Period Fishes

Included freshwater jawless fishes.

Silurian Evidence of Life

Fungi, arachnids, and centipedes were present.

Carboniferous Fishes

Characterized by ray-finned fishes.

First Land Animals

Tetrapods first began moving onto land during the Devonian Period.

Devonian Plants

Ferns appeared during the Devonian Period.

Carboniferous Period

Lasted from 359 to 299 MYA.

Carboniferous Forests

Developed swampy forests.

Permian Period

Lasted from 299 to 251 MYA.

Tetrapods Significance

Signified origin of amniotes during Carboniferous period.

Carboniferous Environmental Change

Polar ice led to sea level drop.

Swampy Forest Significance

Led to lots of fossil fuels.

Mass Extinction Event

Permian/Triassic extinction marked the end of the Permian period.

Reptiles during Permian

Became diversified during the Permian period.

Dominant Plants of Permian

Gymnosperms became dominant.

Amniotes Composition

Included reptiles, birds, and mammals during Carboniferous period.

Cambrian Period Dates

Spanned from 542 to 488 MYA.

Permian/Triassic Extinction Affected Species

Included trilobites, echinoderms, brachiopods, and some fishes.

Permian/Triassic Extinction Significance

Biggest mass extinction in Earth’s history.

Ordovician Period Dates

Spanned from 488 to 444 MYA.

Permian/Triassic Extinction Causes

Possibly caused by volcanic activity and methanogenic bacteria.

Species Affected by Permian/Triassic Extinction

Mostly marine species were affected.

Percentage of Extinctions in Permian/Triassic

90% of species went extinct.

Volcanic Activity Result

Resulted in climate change during the Permian/Triassic extinction.

Paleozoic Era Periods

Included Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and Permian periods.

Triassic Period Dates

Occurred from 251 to 199.6 MYA.

what animals originated in the triassic period?

Dinosaurs and mammals originated.

Mesozoic Era Periods

Included Triassic, Jurassic, and Cretaceous periods.

Jurassic Period Dates

Lasted from 199.6 to 145.5 MYA.

Cretaceous Period Dates

Included within the Mesozoic Era.

Percentage of Extinctions Cretaceous/Paleogene

80% of species went extinct.

Famous Dinosaurs of Jurassic

Included Tyrannosaurus rex, triceratops, velociraptor, and gallimimus.

Hominins Relation to Species

Hominins are not our species.

Jurassic Dinosaurs Diversification

Dinosaurs continued to diversify.

Second Biggest Mass Extinction

Cretaceous/Paleogene extinction.

Neogene Period Dates

Spanned 23 to 2.6 MYA.

Hominin Ancestors

Hominins appeared during the Neogene period.

Paleogene Period Dates

Spanned 65.5 to 23 MYA.

La Brea Tar Pit Animals Age

Less than 40,000 years old.

Quaternary Period Dates

Spans from 2.6 MYA to present.

Homo Sapiens Appearance

First appeared around 200,000 years ago.

Cretaceous/Paleogene Extinction Cause

Impacts by objects from space that caused climate change.

Paleogene Period Diversification

Mammals, birds, flowering plants, and pollinating insects diversified.

Non-Avian Dinosaurs Extinction

Extinguished during the Cretaceous/Paleogene extinction.

Extinct Species in Cretaceous/Paleogene

Included non-avian dinosaurs, pterosaurs, mosasaurs, and many other species.

Triassic Period Life

Survivors of extinction spread and flourished.

Jurassic Flying Reptiles

Pterosaurs lived during the Jurassic period.

Jurassic Marine Reptiles

Included plesiosaurs and ichthyosaurs.

First Bird Species

Archaeopteryx originated during the Jurassic period.

Dinosaurs Diverse in Jurassic

Included sauropods, brachiosaurs, and stegosaurs.