Chapter 15/16- Evolution Flashcards
Natural selection acts upon ___
Phenotypes
Evidence of evolution (5)
- homologous structures
- analogous structures
- vestigial structures
- embyologic similarities
- macromolecules
Chemosynthetic
Use organic molecules as a source of energy instead of the sun light
Convergent evolution
Appear similar but aren’t closely related
Similar environments select similar traits
Homologous structures
Similar features
Share a common ancestor
When the bell curve kinda splits down the middle… Higher in the extreme areas ( n -> m)
Disruptive selection
When the bell curve narrows it’s ____
Stabilizing selection
How many mass extinctions have their been
5
Species :
- physically similar
- successfully interbreed
Postzygotic isolation
Barrier between interbreeding
Embryological similarities
Show genes organisms have in common
Genetic drift
Several alleles r lost in the population due to a random event
(Tree falling over/storm)
Analogous structure
Similar features
Don’t share common ancestors
(Proves that environments select certain abilities)
Vestigial structures
Organisms still have
No longer useful
When the bell curve shifts to another side
Directional selection
Variation
Any difference between organisms
Evidence for evolution
- fossils
- biochem
- vesiigial
Natural selection ___ evolution
Drives
A process called _____ allows new species to be made
Speciation
4 steps of Darwinian Natural selection
- Over production
- Variation
- Competition
- reproduction
Directional selection
One extreme form of the trait is best
Divergent evolution
Related populations or species become less and less like
Coevolution
Two or more species in a close association work with one another and change together
-predator/prey
Darwin theory
-descent with modification due to natural selection
