Exam 17: The Means of Evolution: Microevolution

The gene pool for a particular gene would include:

Evolution by genetic drift is most obvious in:

Cheetahs are not a healthy species. Several million years ago they were widespread in Africa and Asia, but their numbers fell drastically during the last ice age and again when they were hunted to near extinction in the nineteenth century. Now, they suffer from low survivorship (a large number of animals dying), poor sperm quality, and greater susceptibility to disease. Normally, an animal will reject tissue transplanted from another animal, but cheetahs will not reject tissue grafted on to them from another cheetah. What happened to the cheetah? How did their genetic variation change? Where does genetic variation ultimately come from? What mechanism can maintain and increase genetic variation in natural populations?

Which of the following statements about evolution is true?

Which of the following processes is not an agent of microevolution?

________ characters are continuously variable.

Male long-tailed widowbirds have unusually long tails, about 20 inches in length, whereas the females have short tails. In an experiment with long-tailed widowbirds, one group of males had their tails clipped to 5 inches, a second group were left with normal 20-inch tails, and a third group had their tails lengthened to 30 inches by gluing on feathers clipped from the tails of other birds. If sexual selection is responsible for the males having such long tails, predict what will happen when similar numbers of females are placed in the territories of each group of males.

For the Galapagos Islands finch species Geospiza fortis, drought conditions produced a change in the population in which the next generation had larger beaks than the previous one. What produced this change in the population?

The smallest unit that can participate in evolution is a ________.

The greater prairie chicken once flourished on the prairies of Illinois. The conversion of prairie to farmland reduced their numbers from millions to only 50 birds by 1993. Poor genetic diversity resulted in only 50 percent of eggs hatching. Bringing in birds from neighboring states increased their genetic diversity, which improved the egg-hatching rate to 90 percent. These changes in genetic diversity were the result of:

Refer to the figure below, and then answer the question that follows. -Human birth weights are an example of:

If within a large population no mutations occur, no migration occurs, all mating is random, and each individual has an equal chance of reproducing, which of the following will probably happen?

Imagine a population of monkeys in South America whose habitat has been reduced to the point where only 25 monkeys survive. This is an example of:

At its most basic level, evolution is a:

Which of the following is ultimately responsible for introducing new alleles into a population?

Shrews have been documented to travel across frozen lakes and establish populations on previously uninhabited islands; thus, the shrews have a limited gene pool. If this limited gene pool has allele frequencies that are very different from the allele frequencies found in the original population, then this would be an example of:

If every sexually reproducing organism has only two alleles for each gene, how can there be a range of traits seen for a physical characteristic?

The mate-attracting elaborate plumage of the male peacock is a result of:

If after several generations all males have 12-point antlers, this development will have been due to:

If after several generations most males have antlers with 20 points, this development will have been the result of: