History Of Life Flashcards
(36 cards)
Approximate time it took the earth to cool and form a solid crust?
500 million years
Approximate age of the earth?
4.6 billion years
When first microbial fossil evidence emerged?
3.5 billion years
Force that pulled earth into a spherical shape when it was still molten?
Gravity
Elements pulled to the center of core of the earth? (Heavy/light)
Heavier
Elements stayed near the crust or surface of the earth? (Heavy/light)
Lighter
Earths early atmosphere was formed by?
Volcanic gases
Earths early atmosphere had little to no free _____?
Oxygen
Hypothesis describing how earths early environment formed biological material?
Primordial soup hypothesis
First type of cells on earth?
Prokaryotic
Responsible for creating the ozone and free oxygen?
Prokaryotic
A geological record of earths history?
Geological time scale
Eon?
Billion of years
Era?
100’s of million of years
Period?
10’s of millions of years
Epoch?
Few years (1-9 million years)
Mya?
Year
Movement of several large plates that make up the surface of the earth?
Plate tectonics
Movements of mantle which causes tectonics plates to move?
Convection
Movement of plate tectonics causes what kind of changes which influences life?
Environmental
The era during which the ancestors of most major animal group diversified?
Cambrian explosion
Rock layer between the Cretaceous and Paleogene periods characterized by high levels of the element iridium and an abundance of dinosaurs fossils?
The K-T boundary
Any preserved evidence of an organism?
Fossil
Scientist who studies fossils?
Paleontologist