Darwinian Evolution
This is the process by which populations accumulate genetic changes over generations.
What is evolution?
In the Hardy-Weinberg equation, the frequency of all alleles at a particular locus must add up to this number.
What is 1?
This describes evolutionary change occurring within a population over relatively short periods of time.
What is microevolution?
Scientists find the same basic arrangement of bones in a human arm, whale flipper, bat wing, and cat forelimb. These features are said to be this type of structure.
What are homologous structures?
Geographic isolation is an example of this category of reproductive barrier.
What is a prezygotic barrier?
A farmer repeatedly breeds only cows that are large producers of milk. After many generations, milk production in the herd is high and continues to increase as a result of this type of selection.
What is artificial selection?
If the frequency of allele A is 0.7, this is the frequency of allele a.
What is 0.3?
Bottlenecks are an example of this microevolutionary process, which is more common in small populations.
What is genetic drift?
In this type of evolution, two distantly related organisms independently evolve similar characteristics based on similar environmental pressures.
What is convergent evolution?
This type of reproductive isolation occurs when multiple species live in the same habitat, but one species reproduces in the spring while another reproduces in the fall.
What is temporal isolation?
Darwin observed that the organisms on these islands resembled those of mainland South America, but also differed between nearby islands.
What are the Galapagos Islands?
A population has an allele frequency of 0.8 for A and 0.2 for a. According to the Hardy-Weinberg equation (shown below), this is the expected frequency of the Aa genotype.
p2 + 2pq + q2 = 1
What is 0.32?
A few individuals establish a new population on a remote island. This phenomenon describes changes in allele frequency of a new population from the original population.
What is the Founder Effect?
Scientists compare the same DNA sequence in several species. The scientists determine how closely related the species are based on this type of evidence.
What is molecular evidence for evolution?
Mules being sterile are an example of this type of postzygotic barrier.
What is hybrid sterility?
These are the four observations that form the basis of Darwin's mechanism of evolution by natural selection.
What are variation, struggle/limits to population growth, overproduction, and differential reproductive success?
A population is experiencing incoming migration from a different population. As a result, this condition of the Hardy-Weinberg equilibrium is being violated.
What is no gene flow?
In this microevolutionary process, members of a population of birds choose mates based on the shade of the male birds' feathers.
What is nonrandom mating?
Populations experiencing no change in allele frequencies or phenotypic frequencies are said to be in this state.
What is a genetic equilibrium?
This species concept defines a species as a group of natural populations whose members can interbreed and produce viable, fertile offspring, but cannot do so with members of other groups.
What is the biological species concept?
Rather than on an individual basis, evolutionary change is measured at this level.
What is population?
A population has 1,000 individuals. If p = 0.7 and q = 0.3, this is the expected number of heterozygous individuals.
p2 + 2pq + q2 = 1
What is 420?
A population of birds contains individuals with different beak sizes. As a result of this microevolutionary process, birds with either very narrow beaks or very short, wide beaks are most successful at reproducing.
What is natural selection (disruptive selection)?
Scientists construct this type of diagram to illustrate evolutionary relationships between different organisms.
What is a cladogram?
This type of speciation is common in plants.
What is allopatric speciation?