UF BSC 2010 Exam 3Questions with
Verified Answers
parsimony principle - ANSWERS1.) simplest explanation
2.) tree with the fewest character transition
3.) fewest homoplasies
artificial selection - ANSWERS1.) breeding for desirable traits
2.) humans determine an organisms fitness through selective breeding
natural selection - ANSWERS1.) differential reproductive success of certain individuals
with more or less desirable traits
2.) acts on heritable variation in a way that favors the traits that lead to reproductive
fitness and promotes adaptive evolution
3.) only acts on existing variation
4.) DOES NOT act on genotypes, favor the perfect phenotype, or create genetic
variation
heritable - ANSWERScan be passed from parent to offspring
differential reproductive success (DRS) - ANSWERSindividuals with more desirable
traits will be more likely to pass those traits to future generations
evolution - ANSWERSchanges in biological populations (NOT individuals) over time
3 things necessary for natural selection to occur - ANSWERS1.) Variation in the trait
2.) Heritability
3.) Impact on reproductive success
gene pool - ANSWERSsum of all of the alleles for a particular locus in a population
adaptation - ANSWERS1.) beneficial mutation favored by natural selection
2.) refers to both the favored trait and the process by which the trait emerges in the
population
mutation - ANSWERSchange in the nucleotide sequence (random)
2 sources of phenotypic variation - ANSWERSV(g) - genetic variation
V(e) = environmental variation
V(p) = V(g) + V(e)
heritability - ANSWERS1.) (h^2) = V(g)/V(p)
2.) Fraction of variability NOT fraction of trait that is genetic
, parent-offspring regression line - ANSWERSrelates traits of offspring to biological
parents
ex: slope 0f 0.5 -> 1/2 of the variability is due to the parents
Breeder's equation - ANSWERS1.) quantify response to natural selection in terms of
heritability and selection differential (S)
2.) R = (h^2)(S)
selection differential (S) - ANSWERSmeasure of the intensity of selection on a particular
trait
fitness - ANSWERSgenotype and phenotype's contribution to the genetic composition of
future generations; which organisms are more likely to survive AND reproduce
Directional selection - ANSWERSone extreme phenotype is the fittest
mean changes, variance does not
ex: TX longhorns
Stabilizing selection - ANSWERS1.) aka purifying selection
2.) stabilize around intermediate trait as genetic variation decreases
3.) Fitness is highest at average phenotype
4) mean doesnt change, variance changes
ex: human birth weight
Disruptive selection - ANSWERS1.) trait tends toward BOTH extremes
2.) Causes the emergence of two species
3.) bimodal distribution leads to eventual sympatric speciation
4.) rarest of all the selections
ex: bird beaks
frequency-dependent selection (FDS) - ANSWERSoccurs when a phenotype's fitness
depends on how common it is in the population
positive FDS - ANSWERSmost common phenotype is favored
negative FDS - ANSWERSrare phenotype is favored in the poulation
fixation - ANSWERSa given allele is the only allele in the population and all other
variations have been lost
sexual selection - ANSWERS1.) non-random mating in which an organism's phenotype
impacts its choice of mating
2.) traits favored are often costly to males
Verified Answers
parsimony principle - ANSWERS1.) simplest explanation
2.) tree with the fewest character transition
3.) fewest homoplasies
artificial selection - ANSWERS1.) breeding for desirable traits
2.) humans determine an organisms fitness through selective breeding
natural selection - ANSWERS1.) differential reproductive success of certain individuals
with more or less desirable traits
2.) acts on heritable variation in a way that favors the traits that lead to reproductive
fitness and promotes adaptive evolution
3.) only acts on existing variation
4.) DOES NOT act on genotypes, favor the perfect phenotype, or create genetic
variation
heritable - ANSWERScan be passed from parent to offspring
differential reproductive success (DRS) - ANSWERSindividuals with more desirable
traits will be more likely to pass those traits to future generations
evolution - ANSWERSchanges in biological populations (NOT individuals) over time
3 things necessary for natural selection to occur - ANSWERS1.) Variation in the trait
2.) Heritability
3.) Impact on reproductive success
gene pool - ANSWERSsum of all of the alleles for a particular locus in a population
adaptation - ANSWERS1.) beneficial mutation favored by natural selection
2.) refers to both the favored trait and the process by which the trait emerges in the
population
mutation - ANSWERSchange in the nucleotide sequence (random)
2 sources of phenotypic variation - ANSWERSV(g) - genetic variation
V(e) = environmental variation
V(p) = V(g) + V(e)
heritability - ANSWERS1.) (h^2) = V(g)/V(p)
2.) Fraction of variability NOT fraction of trait that is genetic
, parent-offspring regression line - ANSWERSrelates traits of offspring to biological
parents
ex: slope 0f 0.5 -> 1/2 of the variability is due to the parents
Breeder's equation - ANSWERS1.) quantify response to natural selection in terms of
heritability and selection differential (S)
2.) R = (h^2)(S)
selection differential (S) - ANSWERSmeasure of the intensity of selection on a particular
trait
fitness - ANSWERSgenotype and phenotype's contribution to the genetic composition of
future generations; which organisms are more likely to survive AND reproduce
Directional selection - ANSWERSone extreme phenotype is the fittest
mean changes, variance does not
ex: TX longhorns
Stabilizing selection - ANSWERS1.) aka purifying selection
2.) stabilize around intermediate trait as genetic variation decreases
3.) Fitness is highest at average phenotype
4) mean doesnt change, variance changes
ex: human birth weight
Disruptive selection - ANSWERS1.) trait tends toward BOTH extremes
2.) Causes the emergence of two species
3.) bimodal distribution leads to eventual sympatric speciation
4.) rarest of all the selections
ex: bird beaks
frequency-dependent selection (FDS) - ANSWERSoccurs when a phenotype's fitness
depends on how common it is in the population
positive FDS - ANSWERSmost common phenotype is favored
negative FDS - ANSWERSrare phenotype is favored in the poulation
fixation - ANSWERSa given allele is the only allele in the population and all other
variations have been lost
sexual selection - ANSWERS1.) non-random mating in which an organism's phenotype
impacts its choice of mating
2.) traits favored are often costly to males
