The niche of an animal is __________.

SCIENTIFIC THINKING As you learned in symbiotic relationships with mycorrhizal fungi are found in almost all present-day plant lineages. Mosses are a major exception—most mosses lack mycorrhizal associations. Assuming that mycorrhizae were a key factor in the colonization of land by plants, propose an explanation for the absence of mycorrhizae in present-day moss lineages.

A team of 102 scientists spent a year surveying a small area of the San Lorenzo rain forest in Panama to count the number of species of arthropods living there. After collecting 129,494 specimens—using nets, traps, shovels, tree-climbing harnesses, helium balloons, and other creative gear—it took the team eight years to sort and identify the arthropods.The researchers observed a strong correlation between the number of arthropod species and the number of plant species in the San Lorenzo forest. Pose an evolutionary hypothesis to explain this correlation.

The carnivorous plant Nepenthes bicalcarata ('fanged pitcher plant') has a unique relationship with a species of ant—Camponotus schmitzi ('diving ant'). The diving ants are not digested by the pitcher plants, but instead live on the plants and consume nectar. Diving ants also dive into the digestive juices in the pitcher, swim to the bottom, and capture and consume trapped insects, leaving uneaten body parts and ant feces behind. What nutritional impact do the ants have on fanged pitcher plants? Do the pitcher plants derive any nutritional benefit from this relationship?

Under which of the following circumstances would interspecific competition be most obvious?

When goats were introduced to an island off the California coast, the goats inhabited the same areas and ate the same plants as the native deer. The deer population dwindled and finally disappeared. This is an example of __________.

Flounder is a type of fish that looks like the seafloor. This is an example of __________.

The flower fly resembles a honeybee, but the flower fly has no stinger. This is an example of what natural phenomenon?

The poison-arrow frogs Dendrobates of tropical America are all brightly colored and have very similar patterns. Although each species is distasteful to predators and all possess toxic skin secretions, some of the species live quite separately from the others. The adaptive relationship among these species is best termed __________.