Evolution Flashcards
What is evolution?
Change in frequencies of alleles in a population over
Allele- variant of a gene, all diploid organisms have 2 alleles
Ex) cystic fibrosis or different hair color
Population
Organisms of the same species that live together in the same area
Ex) when the environment favors some traits, alleles code for those traits in frequency over time
Origin of earth
4,600,000,000/ 1,000 sheets of toilet paper
Evidence for evolutionary change
1) fossil record
2) comparative anatomy
3) comparative embryology
4) molecular data
5) evolution in action
1) fossil record
Changes over time
Layers of rock contain fossils- new layers cover old ones
Shows series of organisms that lived on earth over a period of time
Fossilize well vs. do not fossilize well
Well- shells, bones, teeth, exoskeletons
Not well- soft tissue, jellies, skin
2) comparative anatomy
Have diff structures but tells store of common ancestor
Homologous structures
Come from same origin
Analogous structures
Look similar
Same function
Diff origin
No evolutionary relationship
Convergent evolution
Not the same, closely related but evolved similar traits
3) comparative embryology
Ex) all vertebrate embryos have all gill pouch at one stage of development
Vestigial structures
No apparent function, but ancestors did posses them
Ex) tons less, appendix, tail bone
4) Molecular record
Compare common genes and proteins
5) evolution in action
Artificial selection - everything we eat, and even dogs
