Gene Flow and Population Dynamics

Gene flow tends to reduce differences between ______ populations.

In areas where the ______ parasite is common, the frequency of the sickle-cell allele is highest.

Heterozygous individuals are ______ to malaria.

Gene flow can ______ neighboring populations into a single population with a common gene pool.

Humans today migrate much more freely than in the past, and gene flow has become an important agent of ______ change in human populations that were previously isolated.

The frequency of the sickle-cell allele is highest in areas where the ______ parasite is common.

Alleles may be transferred that ______ the adaptation of one or both alleles to their local environment.

In some African tribes, the sickle-cell allele accounts for ______ % of the gene pool.

Frequency-dependent selection occurs when the ______ of any one morph declines if it becomes too common in the population.

Copper-tolerant plants are at a ______ and reproduce poorly on nearby soils not contaminated with copper.

Natural selection can act only on ______ variations.

Increased ______ tolerance rapidly spreads within the local population in the bent grass population near copper mines.

Gene flow has resulted in the worldwide spread of ______ -resistance alleles in the mosquito Culex pipiens.

Gene flow can introduce new ______ into a population.

Natural selection may cause the new ______ to increase or decrease in a population.

In some plant species, copper-______ alleles are at a disadvantage and reproduce poorly on nearby soils.

A barnacle may produce more eggs than its neighbors because it is more efficient at ______ food from the water.

Natural selection is the only mechanism that consistently causes ______ evolution.