Evolution Flashcards
Diff modes of natural selection: stabilizing vs directional vs disruptive selection on graphs
phenotype on x axis, # of individuals on y axis; middle peak (towards mean) vs left or right peak vs 2 peaks at end
divergent vs parallel vs convergent evolution
organisms evolve w/ diff characteristics but share common ancestor vs organism evolve w/ similar characteristics to adapt to environ vs organisms evolve w/ similar characteristics but diff common ancestor
Pre vs post zygotic mechanisms and examples
preventing formation of zygote (ex: behavioral like diff style of courtship, temporal like breeding at diff times, mechanical like looking diff, living in diff habitats, gametic like sperm can’t fertilize egg) vs zygote forms but not viable (ex: reduced hybrid viability like hybrids can’t survive, reduced hybrid fertility like sterile hybrids, hybrid breakdown like mating hybrids produce sterile offspring)
Bottleneck effect vs founder effect
When pop is reduced by a great amount due to environmental changes vs when new pop is formed after old pop is isolated
What is vestigial apparatus?
something needed in past species but not current species (think appendix and wisdom teeth)
All chordates possess a?
- Hollow dorsal nerve cord aka spinal cord (this evolved from the notochord)
- pharyngeal slits (ex: fish gills)
- post-anal tail (we used to have tails)
Assortive mating vs disassortive mating
wanting to mate w/ those who share similar traits as you –> offspring = more similar to e/o vs wanting to mate w/ those who have diff traits as you –> offspring = more diff to e/o
allopatric vs sympatric speciation
when 2 groups of animal in same species evolve into diff species due to geographical separation –> no gene flow vs when 2 groups of animal in same species evolve into diff species but NOT due to geographical separation; these groups have to overcome pre/post zygotic barriers
