In 2005, the United States had a population of approximately 295,000,000 people. If the birth rate was 13 births for every 1,000 people, approximately how many births occurred in the United States in 2005?

#Question id: 9216

#Section 2: Evolution

Which of the following criteria have to be met for a species to qualify as invasive?

#Question id: 3465

#Section 4: Behavioural Ecology

One species lives only in tree holes; another species lives only in streams.

#Question id: 10666

#Section 2: Evolution

In a experimental invertebrate population the birth rate is 1200 per 1000 and death rate is 300 per 1000 per generation. Initial population size is 10000. What is value of NET reproductive rate?

#Question id: 11514

#Section 1: Ecology

Which of the following is not an outcome of high population density?

#Question id: 12960

#Section 5: Applied Ecology & Evolution

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.