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exam format

18-20 multiple choice (skip 2)

6-7 definition

3-4 short answers (3-5 sentences/bullets)

1-2 longer answer/required (6-8 sentences)

Evidence of Evolution

C. Biogeography

Biogeographical evidence

fossils that are most similar to living organisms found in the same region
adaptive radiation - evolutionary process in which a lineage shows rapid diversification (speciation) in response to open ecological niches
Hawaiian honeycreepers
convergent evolution - similar selective pressures in different environments have led to selection for similar adaptation

D. Homologies

homology - traits of 2 or more organisms that share a common ancestry
Analogy - traits of 2 or more organisms that share a common function
Evolutionary trees are diagrams that reflect hypotheses about the relationships among different groups
homologies form nested relationships in trees
Different types of data can be used to construct trees (DNA, anatomy, fossils)
analogous traits are not useful in trees

Vestiges as evidence

vestigial structures - structures or organs that no longer perform the function for which they evolved
- ex: wings of flightless birds
- eyes of blind organisms (burrowers and cave dwellers)
- hind limbs or organisms (snakes, whales, and dolphins)
- appendix

Atavisms as evidence

atavism - sporadically expressed remnants of ancestral traits
unlike vestigial structures, not present in every individual
- ex: tail bone in humans
Some can be produced in a lab
genes that produce traits do not necessarily disappear when the trait is reduced or becomes nonfunctional
pseudogenes - genes that are nonfunctional descendant species that functioned to produce a specific trait in the ancestral species

Embryological Evidence

Genetic Evidence

Bad Design as evidence for evolution