Exam 16: How Populations Evolve

If two adjacent populations of the same species show gene flow,then the two populations will

British land snails are an example of disruptive selection.In the grassy fields,the light-banded snails escape bird predators.In the darker forest,the dark snails survive and the light-banded snails are eaten.As long as the snails continue to cruise across the British landscape mating at the same season,why doesn't this "disruptive selection" eventually lead to two separate species?

Which of the following conditions is necessary to maintain the Hardy-Weinberg equilibrium?

A population of organisms that reproduce asexually without gametes from other individuals will display more variation than a population that reproduces sexually.

In a population,the allele frequency for red flower color remained at 0.7 and the allele frequency for white flower remained at 0.3 for six generations.This ____ an example of a Hardy-Weinberg equilibrium in that ___________.

While we have seen how natural selection and the use of pesticides can lead to the development of resistant varieties of insects,two economically important flies,the Mediterranean fruit fly (Medfly)and the screwworm fly,can be driven to local extinction by the continuous release of sterile flies of those species.The critical factor is that the female of these species only mates once.But which of the following is/are also necessary for sterile release to work?

A certain species of butterfly varies in color from white to dark blue.The birds found in the same area feed on the white or lightly colored butterflies,leaving butterflies that are darkly colored.This may result in what type of selection?

What is the term used to describe the changes in allele frequencies of a population over generations?

Which of the following is required for natural selection to occur in a population?

Which of the following is/are a biological "population?"

Which statement is NOT true about the Founder Effect?

What do the Founder Effect and the Bottleneck Effect have in common?

The Hardy-Weinberg equilibrium is usually met in populations in changing environments.

Which of the following is true about genetic drift?

Our domesticated honey bee-originally from Europe-is slow to sting,requires abundant flower nectar,gets up late in the morning,and stores much honey but only produces enough new brood to swarm once a year.Because the European honey bee was performing poorly as a honey producer in South America,the African subspecies was imported in a breeding experiment.The African honey bee formed small nests,foraged earlier and on smaller nectar sources,produced less honey stores and more brood,swarmed four or five times a year,and was fast to sting.However,when the African queens escaped,the two populations interbred and the African genotype spread several hundred miles north each year.Surprisingly,a hundred miles behind the expanding range of the African honey bees,the European and hybrid strains died out and the bees were essentially 100 percent African.How would this be explained in evolutionary genetics terms?

Which of the following examples will help maintain diversity within a population?

Gene mutation occurs at any time,without respect to the mutation's adaptive value or benefit to the organism.

Another student proposes that handedness could just as easily be passed to children by how the parents carry the child and interact with it,a learning process that may perpetuate from the parents' handedness.Assuming all parents and children are expressing their "true handedness," the occurrence of which case below would cast the most serious doubt on a simple genetic basis for handedness,with left-handedness recessive?

While studying gull egg laying abilities a researcher noted that the birds laid an average of 7 - 9 eggs per clutch at the beginning of the study.After studying the population for 15 generations the researcher noted that the birds now laid an average of 3- 4 eggs per clutch.What type of natural selection is occurring in the population of gulls?

Which of these conditions is NOT among the requirements of the Hardy-Weinberg equilibrium of allele frequencies in a population?