Evolution and Speciation Flashcards
what is a microevolution?
change in populations allelic frequencies
what is a macroevolution?
- large change in appearance, behavior, physiology
- long period of time
what are the 5 points of darwin’s theory?
- individuals of species may vary
- some variations are heritable
- the more individuals are produced than the environment can support
- competition for resources
- individuals with most favorable traits survive
what are the 2 points of natural selection?
- acts upon phenotypes
- survivors are fit
what are the only changes to dna that can be passed down?
mutations
what is genetic recombination?
sexual reproduction that creates new combinations of genes
what is variation by migration?
individuals remove and add variations when they enter and leave
what are 3 variations?
- morphological variations
- chromosomal variations
- protein variations
what does it mean for a population to be in H-W Equilibrium?
a state of constant gene frequencies in a population
what things keep a population from being in the equilibrium?
- mutations
- migration
- natural selection
- genetic drift
- random mating
how do biologists define a species?
a biological species has members that make fertile offspring
what is allopathic speciation?
- population split into 2 or more populations
- diverse genetically due to selective forces
- migration away
what is sympatric speciation?
- speciation within a population
- nondisjunction of chromosomes
sympatric: what is polyploidy?
chromosomes don’t separate and creat multiple sets of chromosomes in gametes
sympatric: what is autopolyploidy?
doubling of chromosomes number in the population (new species)
sympatric: what is allopolyploidy?
two species donating gametes and the chromosomes double
what are different prezygotic isolating mechanisms?
to remember: take my goofy, beaded hat TMGBH
- habitat differences
- temporal differences
- mechanical differences
- behavioral differences
- gametic differences
what are temporal differences?
breeding during a certain time
what are mechanical differences?
mating is attempted but failed
what are gemete differences?
sperm can’t fertilize other species
what are behavior differences?
attraction barriers
what are habitat differences?
don’t see each other
what are the 3 postzygotic isolating mechanisms?
- zygote doesn’t survive gestation
- offspring sterile
- hybrid break down
what are the dominant frequncies labeled as?
P^2
what are the heterozygote frequencies labeled as?
2pq
what are the recessive frequencies labeled as?
q^2
what are the 5 things needed to design a lab?
- variable
- control
- data collected
- randomization
- multiple trials
