Exam 16: How Populations Evolve

Evolution by genetic drift is most obvious in

In a population, the most common phenotype represents the dominant allele.

Explain why new mutations appear frequently in bacterial populations but infrequently in human populations.

The interaction of genes and environment produces a specific

Natural selection acts on individual phenotypes to affect the evolution of .

Shrews have been documented to travel across frozen lakes and establish populations on previously uninhabited islands. The low level of genetic diversity in the new populations is the result of

Male fish that display a bright blue color attract more mates as well as more predators. Maintaining that blue gene in the population is an example of

What conditions are necessary for a population to be at equilibrium?

The nonliving components of an environment, such as weather and water availability, are

According to the mathematical equation used in the Hardy- Weinberg principle, if the alleles for a certain trait in a population are A1 and A2, then the proportion of individuals with the genotype is represented by 2pq.

Imagine a population of monkeys in South America whose habitat has been reduced to the point where only 20 individuals survive. This is an example of

Suppose a small population of deer is introduced to an island. All of the original males have 6 to 10 points on their antlers, and the average male has 8 points. After several generations, if most males have antlers with 10 points and no males have 6 points, the population has undergone selection.

Within a large population, if no mutations occur, no migration occurs, all matings are random, and each individual has an equal chance of reproducing, which of the following will probably happen?

The process by which allele frequencies are altered in a small population due to chance is called

In some butterfly populations, there are equal frequencies of alleles that code for black and yellow coloration. This is an example of

Zoos often loan animals to other zoos for breeding purposes. From an evolutionary standpoint, what is the benefit?

A population carries two alleles for a trait in which T is dominant and t is recessive. In the Hardy- Weinberg equation, q2 represents the

Mutations

The Pennsylvania Amish have a very high frequency of an unusual allele that results in short arms and legs and extra fingers. This high frequency is thought to be the result of

Populations of organisms are constantly evolving, which means that they are always