define..
define artificial selection
humans can affect diversity within a population
what specific species did darwin use to support his theory of evolution
galapagos island finches
geographical isolation
answer varies but definition is change in climate or geographical change over time that splits an originally single population
what's a vestigial structure
anatomical feature or behavior that doesn't have a purpose
non random mating
living things don't mate at random
evolutionary fitness
how well a species is able to survive and reproduce in its environment
fill in the blank: natural selection acts on ______ while evolution acts on _________.
1. individuals
2. populations
give an example of a prezygotic barrier
emporal, habitat, behavioral, mechanical, or gametic isolation
define difference in microevolution & marcoevolution
macro: if two populations can no longer interbreed,new species are born
mutation
random changes to dna; errors in mitosis and meisos
sexual selection
selecting mates based on advantegous traits
what's the difference between a prezygotic barrier and a postzygotic barrier?
prezygotic prevents mating or fertilization between species and postzygotic barrier reduces viability or reproductive capacity of hybrid offspring
people taking airplanes to diff countries
what are the 5 agents of evolutionary change
1. mutation
2. gene flow
3. nonrandom mating
4. genetic drift
5. selection
rapid speciation
new spcies filling new niches, because they inherited successful adaptions
define the founder and bottleneck effect of genetic drift
founder: occurs when a few populations become isolated from a larger population; small group splinters off and starts a new population
bottleneck: some factor (disaster) reduces population to small number and then the population recovers and expands again
what's the difference between convergent and divergent evolution?
convergent is when unrelated species become similar over time
divergent is when related species become more different as a result of artificial selection or adaptive radiation
give an example of how darwin & lamarck implied their theories
lamarck & darwin example is comparison of giraffes
how many evidences are there of evolution - define 4-5
10;
biochemistry, similar genes, comparative anatomy, homology, vestigial structures, fossil record, transitional fossils, geography, antibiotic resistance, & embryonic development
adaptive radiation
diversification of a group of organisms into forms filling different ecological niches; many different species from one common ancestor
define darwin's theory and lamarck's theory of evolution and how they're different (who's right?)
darwin: competition for limited resources results in differential survival so individuals with more favorable phenotypes are more likely to survive and produce more offspring, thus passing traits to further generations
lamarck: organisms adapted to their environment by aquired traits through use and disuse
darwin theory is right
what's the difference between phyletic gradualism and punctuated equilibrium?
equilibrium: not lots of change/evolution but then disruptive events prompt rapid evolution
give an example of stabilizing, disruptive, and directional selection
answer varies
define and explain the three different types of selection
1. directional - shifts overall makeup of the population by favoring variants that are one extreme of the distribution
2. disruptive - favors variants at both ends of the distribution
3. stabilizing - removes extreme variations from the population and preserves intermediate types
how did darwin use finches to prove his theory (also incorporate the 2 scientists whoefw researched the finches after the drought we learned in class)
natural selection of beaks; more finches w certain types of beaks came in population bc of drought that caused food sources to lack