The Norway rat (Rattus Norvegicus), a widespread pest, was controlled for about a decade by the anticoagulant warfarin. This chemical substance, placed in food pellets, is absorbed by the intestinal tract and inhibits the clotting of blood. After a population decline for about 10 years, rat populations increased and stabilized. In one European population, as illustrated in the graph below, the percentage of rats resistant to warfarin has remained fairly stable over a number of years.

Resistance to warfarin is governed by a dominant autosomal gene, R. More than 15 percent of the resistant animals are heterozygous at this locus (Rr). The table below indicates the response to warfarin and relative reproductive fitness of individuals that are homozygous or heterozygous for the dominant gene (R). The RR individuals have a 20-fold increase in vitamin K requirement over individuals.

Fitness is a measure of the reproductive success of a particular genotype. The highest fitness is 1.00.

Which of the following is most likely correct concerning the gene for resistance to warfarin? 

#Question id: 11714

#Section 2: Evolution

In recognizing patchiness in the natural world, ecologists have developed three different models of populations. Which of these recognize(s) that there are differences in the quality of habitat patches without considering effects of differences in habitat quality within the habitat matrix?

#Question id: 11715

#Section 2: Evolution

The lifetime dispersal area of a particular species of drosophila is 0.2 km2. What else would we need to know to determine the neighbourhood size for this species?

#Question id: 11716

#Section 2: Evolution

Macroecology addresses patterns of range size and population density. Which of the following statements is true?

#Question id: 11765

#Section 2: Evolution

The population density of a particular insect species was determined to be 15,000 adults per hectare in the summer of 1996, 21,000 adults per hectare in the summer of 1997, and 29,400 adults per hectare in the summer of 1998. Based on these population estimates, what is your estimate of λ, the annual rate of geometric growth?

#Question id: 11766

#Section 2: Evolution

The population density of a particular insect species was determined to be 15,000 adults per hectare in the summer of 1996, 21,000 adults per hectare in the summer of 1997, and 29,400 adults per hectare in the summer of 1998.

What would you expect the insect population to be in the summer of 2000, assuming no change in λ?

#Question id: 11767

#Section 2: Evolution

If a population has a stable age distribution, which of the following statements is true?