Evidence of Evolution

EQ: What evidence convinced Darwin that species could change over time?

TEK 7ACDE (Supported by 5 branches of science)

E

VIDENCE OF

E

VOLUTION

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The Fossil Record (Paleontology)

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Geographic Distribution of Living Things (Geography)

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Body Structures (Anatomy)

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Similarities in Early Development (Embryology)

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Similarities in Genes and Proteins (Biochemistry)

Evidence for Evolution

-

Paleontology

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The Fossil Record

-Layers of ground show

change

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Similarities

between current and ancient species ● Older fossils,

less like modern species

● Fossil record not complete because

most organisms don’t form fossils

 Gaps filled in as more discovered (Transitional Fossils)

Evidence of Evolution -

Geography

Beaver Muskrat Beaver and Muskrat Coypu Capybara Coypu and Capybara ●

Geographic Distribution of Living Things-

similar environments have similar types of organisms

E VIDENCE OF E VOLUTION

- A

NATOMY

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Homologous Structures

- structures that have different mature forms in different organisms, but develop from the same embryonic tissue ●

similar characteristics resulting from common ancestry

Look at color coding of bone structures!

Evidence for Evolution –

Anatomy

continued…

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Vestigial organs

- organs that serve little or no useful function in an organism ● ● ● remnants of structures that had important functions in ancestors shrink/get smaller over many generations examples: ● snakes: pelvic bone/hindlimbs ● ostrich: wings ● human: appendix

Flightless bird Eyeless Cave Fish

E VIDENCE OF E VOLUTION -

E

MBRYOLOGY

● Compare anatomy of embryos ● Similarities of development or structures that are not obvious in adult ●

Embryos of vertebrates are similar in appearance early in development

, but may grow into

different structures in adult

● Evolution from common ancestor

E VIDENCE OF E VOLUTION - B IOCHEMISTRY

● The more similar the DNA and amino acid sequence in proteins, the more likely it is they diverged from

common ancestor

● Provides evidence when species are so closely related they do not appear to be different …or… ● when species are so diverse that they share few similar structures