kill me (it's not complete yet)
VIDA
variation
inheritance
differential survival + reproduction
adaptation
Natural selection
prolific rep. of individuals w/ favorable traits that survive environmental change bc of those traits
“inherited modifications”
only known mech. for adaptive evolution
2 main mechanisms of genetic diversity
mutation & sexual reproduction
Mutation
change in DNA
outcomes of mutation
reduced fitness
beneficial effect on fitness
no effect on fitness (neutral mutations)
how sexual reproduction leads to genetic diversity
2 parents = unique combination of alleles —> unique genotypes + thus phenotypes in offspring
Adaptation
hereditable trait that helps an organisms’s survival and reproduction in present environment
Divergent evolution
two species that evolve in diverse directions from a common point —> variation in form + function
ex. flowers all have a common ancestor
Convergent evolution
similar traits evolve independently in species that do not share a recent common ancestry
trait in 2 species came to be similar in structure + have the same fuction but did so independently
ex. bats + incests can fly
Evidence of evolution
fossils
anatomy + embryology (bones)
biogeography
molecular biology
Homologous structures
bones shape + sizes change but they maintain the same overall layout
Vestigial structures
unused structures w/out function
ex. tailbone in humans
Analogy aka homoplasy
when similar characteristics occur bc of environmental constraints and not due to close evolutionary relationship
happens bc of selection pressure
embryology
study of anatomy of an organism’s development into it’s adult form
some organisms have structures in their embryonic form that disappear when they reach adult or juvenile form
biogeography
study of geographic distribution of organisms across the planet
species can be region specific based on WHEN they developed (pre or post continental divide)
molecular biology
DNA’s universality + structural differences in ribosomes + membranes reflect common ancestry + decent w/ modification
gene duplication in evolution
allows new protein functions to evolve while maintaining the original function
Things to note
INDIVIDUALS DO NOT EVOLVE
IT ISN’T THE ORIGIN OF LIFE
EVOLUTION IS NOT GOAL DIRECTED
3 primary sources of genetic variation
mutation
gene flow
sex
Gene flow
any movement of genetic material from one population to another
Fitness
how good a particular genotype is @ levaing offspring in the next generation relative to otehr genotypes
artificial selection
when people select which organisms get to reproduce (instead of nature)
ex. farmers and breeders choosing traits
Thomas Malthus
economist who published essay explaining competition for resources among humans —> influenced Darwin + Wallace
Georges Cuvier
He established proof that many species had become extinct in past ages and that after catastrophes new species had been created —> influenced Darwin + Wallace
Charles Lyell
Geologist who provided geological and fossil evidence to support Darwin’s theory (long time span proven). He proposed that Earth is extremely old and processes that changed the Earth in the past are still @ work today
Charles Darwin
If you don’t already know what he did ur cooked. Biggest name in evolution EVER
Alfred Russel Wallace
Same thing as Darwin at the same time just doesn’t get credit
Modern synthesis
the coherent understanding of the relationship btwn natural selection and genetics
Microevolution
a change in gene frequency within a population (small scale)
Macroevolution
process that gave rise to new species + bigger taxonomic groups w/ widely divergent characters
evolution of groups larger than an individual. Macroevolution encompasses the grandest trends and transformations in evolution, such as the origin of mammals and the radiation of flowering plants
population genetics
study how selective forces change a pop. through changes in allele and genotypic frequencies
gene pool
sum of all the alleles in a population
genetic drift
when allele frequencies in a population changes randomly with no advantage to the pop. over existing allele freq.
founder effect
an event that initiates an allele freq. change in an isolated part of the pop. which is not typical of the original pop.