A
The field of biology that studies allele frequencies in populations and how they change over time is called__________.
population genetics.
Microevolution is sometimes contrasted with_________.
macroevolution
is a group of organisms of the same species that are found in the same area and can interbreed.
population
is a version of a gene, a heritable unit that controls a particular feature of an organism.
An allele
refers to how frequently a particular allele appears in a population.
Allele frequency
____________refers to how frequently a particular allele appears in a population.
Allele frequency
Genetics and evolution go hand in hand. Darwin explained that some favorable traits would increase in frequency over time. We now know that these traits are controlled by alleles. This shift in frequency of alleles is known as_______________.
microevolution
. Natural selection acts at the level of the individual; it selects for individuals with greater contributions to the gene pool of the next generation, known as an organism’s______________.
evolutionary (Darwinian) fitness.
___________allows researchers to determine which individuals are contributing additional offspring to the next generation, and thus, how the population might evolve.
relative fitness
If natural selection favors an average phenotype, selecting against extreme variation, the population will undergo_________________.
stabilizing selection
When the environment changes, populations will often undergo__________.
directional selection
This form of evolution involves large changes, such as formation of new groups or species, and happens over long time periods.
macroevolution
Another type of selection, called______________, favors phenotypes that are either common or rare.
frequency-dependent selection
The bigger, stronger, or more decorated males—get the vast majority of the total mattings.
sexual dimorphisms
____________ states that males develop these impressive ornaments to show off their efficient metabolism or their ability to fight disease.
The good genes hypothesis
Global warming has caused the once snowy mountainside to now turn into a rocky landscape with little snow. Over the last century the species mice which reside in these mountains have started to change in coat color. The population of mostly white mice have shown an increase in frequency of gray individuals. What type of evolutionary process is happening to this population of mice?
Responses
Directional selection
_________ tells us how much phenotypic variation in a population is ultimately due to genetic differences as opposed to acquired differences.
heritability
The diversity of alleles and genotypes within a population is called__________.
genetic variance.
the mating of closely related individuals, which can have the undesirable effects.
inbreeding
Another way a population’s allele and genotype frequencies can change is________.
genetic drift
Genetic drift can also be magnified by natural events, such as a natural disaster that kills a large portion of the population, known as the__________.
bottleneck effect
This effect occurs when the genetic structure changes to match that of the new population’s founding fathers and mothers.
The founder effect
Another important evolutionary force is__________.
gene flow
the flow of alleles in and out of a population due to the migration of individuals or gametes
gene flow
A population of monkeys with varying fur colors lives on a small island off the coast of central america. Recently a wildfire wiped out over half the population of monkeys on that island leaving behind only about 30% of the original population. The monkeys left behind are now responsible for repopulating the island and the offspring will have only traits carried by those monkeys left behind. What type of genetic drift is this population experiencing?
The Bottleneck Effect