Exam 16: How Populations Evolve

Female finches, which do not sing, often choose to mate with males that sing a specific, elaborate song. This is an example of

A population of hummingbirds with a variety of beak sizes finds a new food source in a plant that has a long trumpet flower with nectar at the bottom of the trumpet. Over time, these hummingbirds develop longer beaks. This is an example of

Having greater evolutionary fitness means

Suppose that the only remaining population of a certain reptile species lives on an African mountain and that there is no migration out of this large but isolated population. Which of the following describes the most likely future of this reptile population?

In hamsters, the dominant allele B codes for a black coat and the recessive allele b codes for a tan coat. In the population shown in the figure above, what is the most frequent phenotype?

A population of plants comes in two flower colors: blue and white. Crossing two blue- flowered plants produces mostly blue- flowering offspring and some white- flowering offspring. Crossing two white- flowered plants produces only white- flowering offspring. This indicates that the white- flowering plants are

A bird comes in a range of phenotypes, from white through gray to black. Disruptive selection favors the gray phenotype.

If two or more phenotypes in a population are both favored by selection, what is happening?

Suppose a population of mostly sand- colored crabs migrates from a sand beach to a pebble beach and evolves a darker, speckled coloration that closely resembles the pebble beach. This is an example of

Which of the following can affect a small, endangered population so severely that it goes extinct?

The use of antibiotics caused the mutation that produced methicillin- resistant Staphylococcus aureus (MRSA).

Genetic drift results in a change in allele frequencies because

As predator and prey species acquire new adaptations to help them survive the constant "arms race" between them, what evolutionary phenomenon is occurring?

The 30,000 elephant seals alive today are genetically very similar due to

In general, each species of fruit fly in the Hawaiian archipelago is restricted to a single island. One hypothesis to explain this pattern is that new species formed after a small number of flies colonized each new island. This mechanism of speciation is called

A population is defined as

A population carries two alleles for a trait in which T is dominant and t is recessive. In the Hardy- Weinberg equation, 2pq represents the

Antibiotic resistance is a result of in bacteria.

A population with _ _ is at risk for extinction.

If the tallest and shortest individuals of a population of humans do not survive and reproduce as well as the individuals of "average" height, which type of selection would most likely result?