Exam 15: A: Nonadaptive Evolution and Speciation Urban Evolution

A new volcanic island has formed in the Pacific Ocean.The island has a broad shoreline exposed to salt winds; fertile volcanic soils are an at elevation of 50 feet; and steep,rocky hills range from an elevation of 60 feet up to a peak of 1000 feet.In the upper elevations,snow forms on a regular basis but melts away on most days.Many clusters of seeds from a coastal plant species blow onto the new island during a typhoon,and the seeds germinate all over the island,but only a few plants survive in each location,the others are unable to tolerate the conditions.What would the descendants of these plants look like in a few millennia?

If a flood causes the death of 50% of small mammals,which population would exhibit the most loss of genetic diversity in its future generations?

Spotted skunks and striped skunks have overlapping habitat ranges,but no hybrid offspring are produced.Spotted skunks breed in the fall,striped skunks breed in the spring.This is an example of

Is reproductive isolation among populations of the same species always detrimental to their survival? If yes,explain why.If no,give one example when reproductive isolation is a problem and one example when it is not.

A male from species A mates with a female from species B.Male A's sperm swims and finds the egg,but the sperm is unable to penetrate the egg.This is an example of

Which of the following can influence the evolution of a species?

A scientist is studying the population genetics of a butterfly population inhabiting a group of islands off the coast of California.The mainland population has the greatest allelic diversity.Island A has lower allelic diversity than the mainland,and island B has lower diversity than island A.All the alleles found on island B are also found on island A.The allelic diversity of island C is the same as the allelic diversity of island B,but half of the alleles on island C are not found on islands A and B.Which of the following scenarios best explains this pattern?

An island has a population of 10,000 birds that has 98% gray individuals and 2% black individuals.Generation after generation,this ratio and population size remains basically the same.After a hurricane,10,000 black birds are blown onto the island.What will happen to the population?

You are a geneticist studying the population genetics of barn swallows.You are particularly interested in one gene,and upon examining the 100 alleles present in 50 individuals,you find that one allele is quite common,accounting for 30 of those alleles.The allelic frequency of this allele is

The total collection of alleles in a population is the

Would you expect members of the same family,same genus,or same species to share the most characteristics with one another? Explain.

Why doesn't the egg cell receive the mitochondria found in a sperm cell?

Gray foxes inhabiting the eastern United States were examined for mitochondrial diversity.In the southern region,32 variants were found,while in the northern region,only four variants were found,all of which were also present in the southern populations.Given this,what do you believe is the most likely pattern of evolution?

An extremely harsh winter causes the death of 75% of an endangered antelope population.When considering the future survival of this population,which of the following is a concern for scientists?

Population genetics is the

Give an example of an organism that lacks mate selection.

Which of the following is a human-caused environmental change that animals face?

During the building of the London subway system in the late 1800s,a species of aboveground-dwelling mosquito expanded its distribution to include the underground tunnels,where it successfully lived and bred.In the late 1990s,scientists comparing the two groups of mosquitoes discovered that they are now different species.The most likely mode of reproductive isolation for these two species is

An island has a population of 100,000 moths that has 98% gray individuals and 2% black individuals.Generation after generation,this ratio and population size remains basically the same.After a hurricane,10,000 black moths are blown onto the island.This is an example of

Why is genetic diversity important for the survival of a species?