Which of the following statements about the evolution of life histories is correct?

a.Unstable environments with unlimited resources favor r-selected populations.

b.K-selected populations are most often found in environments where density-independent factors are important regulators of population size.

c.Most populations have both r- and K-selected characteristics that vary under different environmental conditions.

d.The reproductive efforts of r-selected populations are directed at producing just a few offspring with good competitive abilities.

TLS Online TPP Program

#Question id: 12104

#Unit 10. Ecological Principles

Two barnacles, Balanus and Chthamalus, can both survive on the lower rocks just above the low-tide line on the Scottish coast, but only Balanus actually does so, with Chthamalus adopting a higher zone. Which of the following best accounts for this niche separation?

TLS Online TPP Program

#Question id: 12105

#Unit 10. Ecological Principles

A species of fish is found to require a certain water temperature, a particular oxygen content of the water, a particular depth, a rocky substrate on the bottom, and a variety of nutrients in the form of microscopic plants and animals to thrive. These requirements describe its 

TLS Online TPP Program

#Question id: 12106

#Unit 10. Ecological Principles

Which of the following best describes resource partitioning?

TLS Online TPP Program

#Question id: 12107

#Unit 10. Ecological Principles

As you study two closely related predatory insect species, the two-spot and the three-spot avenger beetles, you notice that each species seeks prey at dawn in areas without the other species. However, where their ranges overlap the two-spot avenger beetle hunts at night and the three-spot hunts in the morning. When you bring them into the laboratory, their offspring behave in the same manner. You have discovered an example of

TLS Online TPP Program

#Question id: 12108

#Unit 10. Ecological Principles

Resource partitioning would be most likely to occur between

TLS Online TPP Program

#Question id: 12109

#Unit 10. Ecological Principles

Niches of two coexisting species of pond snail of the same genus are likely to be similar, but not identical, because of which of the following?

I. Closely related species use similar resources.

II. Competitive interactions exist between these species. 

III.  Unlimited resources are available.