Week 2 Flashcards
A record of life forms and geological events in Earth’s history.
Geological time scale
are a set of principles that describe how rock layers are deposited and change over time. These laws are used to identify strata and understand Earth’s history.
Stratigraphic laws
Remnant, impression, or trace of an animal or plant of a past geologic age that has been preserved in Earth’s crust.
Fossils
Major geological events
Eons
Era
Periods
Epoch
Eon
Hadean
Archean
Proterozoic
Phanerozoic
Era
Paleozoic
Mesozoic
Cenozoic
Periods
Cambrian
Ordovician
Silurian
Devonian
Carboniferous
Triassic
Jurassic
Cretaceous
Tertiary
Quarternary
Epochs
Paleocene
Eocene
Oligocene
Miocene
Pliocene
Pleistocene
Holocene
__, The largest division of geologic time scale; -__to nearly __ of years.
Eons
Half billion
Billions
Eons is divided to two
Precambrian
Phanerozoic
Precambrian
__% of the Earth’s History
Composes of
88%
Hadean
Archean
Proterozoic
derived from the word Hades (god of the underworld in Greek mythology)
Hadean eon
__, Presence of __ due to the emergence of __.
Proterozoic eon
Oxygen
Cyanobacteria
Present eon
Phanerozoic Eon
Phanerozoic is subdivided into 3 eras
Paleozoic
Mesozoic
Cenozoic
__, periods of __ to __ years.
Era
Tens
Hundreds of million
Paleozoic era is also called__, started __ million years ago.
Ancient or old life
540
Peiods are no more than __
Million of years
Explosion of new kinds of organisms
Cambrian period
__, Many types of primitive animals called __ evolved
Cambrian
Sponges
__, Small ocean invertebrates (Animals without backbones) called __.
Cambrian
Trilobites
The ocean were filled with invertebrates of many types.
Ordovician
The first fish evolved.
Ordovician
Plants colonized the land for the first time, but animals still remained in water.
Ordovician
In the oceans, corals appeared and fish continued to evolve.
Silurian
The first seed plant evolved.
Devonian
Seeds had a protective coat and stored food to help them survive. Seed plants eventually the most common type of land plants.
Devonian
__, Fish with __ evolved. They could breathe air when they raise their heads above water.
Devonian
Lobe fins
With special tissues to circulate water and other materials, they could grow larger than earlier. Non vascular plants.
Silurian
Widespread forests of huge plants left massive deposits of carbon that eventually turned to coal.
Carboniferous
The first amphibians evolved to colonize land, but they had to return to the water to reproduce.
Carboniferous
The first reptiles evolved. They were the first animals that could reproduce on dry land.
Carboniferous Period
All the major land masses collided to form the supercontinent.
Permian
Temperatures were extreme, and the climate was dry.
Permian
Temperatures were extreme, and the climate was dry.
Plants and animals evolved adaptations to dryness, such as waxy leaves or leathery skin to prevent water loss.
Permian
The first dinosaurs branched off from the reptiles and colonized and colonized the land, air, and water.
Triassic Period
Huge seed ferns and conifers dominated the forests, and modern corals, fish, and insects evolved.
Triassic
The Supercontinent started to separate.
Triassic
Dinosaurs reached their peak in size and distribution.
Cretaceous Period
Earth’s overall climate was warm; even the poles lacked of ice.
Cretaceous
This period ended with the dramatic extinction of the dinosaurs.
Cretaceous Period
The continents were close to their current location today.
Cretaceous Period
__, “Recent Life”; started __ million years ago and continues up to the present.
“Age of Mammals”
Cenozoic era
65
Earth’s climate was generally warm and humid.
Mammals evolved
Tertiary Period
