Evolution an the Origin of Species

Evolution

the origin of species and how organisms change over time.

Evolution

change in organisms across generations.

Theory of evolution

Alfred Russel Wallace and Charles Darwin.

Evolution

change over time.

Natural Selection

mechanism of change.

How does Evolution occur?

natural selection, mutation, random genetic drift, and migration.

Theory of Natural Selection

1. variation among individuals.

2. heritable traits.

3. only small fraction will survive

4. populations will change & become adapted, well suited traits survive and reproduce, passing traits to future generations.

Natural selection

process of choosing based on the organism’s traits.

Evolution

is not random.

Endemic Species

native species that do not exist anywhere else.

Darwin Hypothesized

that south-American species had colonized the Galapago’s island.

Allopatric Speciation

the formation of a new species in geographic isolation.

Names of the 3 rivers

Owens, Amargosa, Mojave.

Phylogenetic Tree

A graph that shows the evolutionary relationship between species.

Allopatric Speciation Ocurs

when populations become geographically isolated.

3 Eras

1. Cenozoic (66 mya) ongoing

2. Mezoic (245 mya) 65mya

3. Paleozoic (70mya) 244 mya

Which Era was dominated by reptiles including dinosaurs?

Mesozoic Era.

Eras are divided into?

Periods.

Periods of the Mesozoic era

Cretaceous, Jurassic, Triassic.

Paleozoic Era

Tribolites, belong to phylum Antropoda.

Mesozoic Era

Tyrannosaurus rex

Cenozoic Era

Sabre-tooth cat

“missing link”

the fossil record is incomplete.