The upper forelimbs of humans and bats have fairly similar skeletal structures, whereas the corresponding bones in whales have very different shapes and proportions. However, genetic data suggest that all three kinds of organisms diverged from a common ancestor at about the same time. Which of the following is the most likely explanation for these data?

#Question id: 9213

#Section 2: Evolution

Suppose you attend a town meeting at which some experts tell the audience that they have performed a cost-benefit analysis of a proposed transit system that would probably reduce overall air pollution and fossil fuel consumption. The analysis, however, reveals that ticket prices will not cover the cost of operating the system when fuel, wages, and equipment are taken into account. As a biologist, you know that if ecosystem services had been included in the analysis, the experts might have arrived at a different answer. Why are ecosystem services rarely included in economic analyses?

#Question id: 9214

#Section 2: Evolution

Researchers have been studying a rare population of 87 voles in an isolated area. Ten voles from a larger population were added to this isolated population. Besides having ten additional animals, what benefits are there to importing individuals?

#Question id: 9216

#Section 2: Evolution

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

#Question id: 9217

#Section 2: Evolution

Which of the following conditions is the most likely indicator of a population in an extinction vortex?

#Question id: 9218

#Section 2: Evolution

What strategy was used to rescue Illinois prairie chickens from a recent extinction vortex?

#Question id: 9219

#Section 2: Evolution

If the sex ratio in a population is significantly different from 50:50, then which of the following statements will always be accurate?