Chapter 15

A group of interacting species that occur together at the same place and time is known as a(n)

Despite having a relatively small biomass, populations of grizzly bears often have strong effects on their communities. The grizzly bear is therefore an example of a

The lowest possible value of the Shannon index is _______. Low values indicate _______ species diversity.

The Shannon index is determined by applying the _______ to the proportion of each species in a community, multiplying it by the proportion once again, and then summing those values.

In a food chain, secondary consumers are _______ primary producers.

The trophic facilitation phenomenon described by Hacker and colleagues involves direct interactions between two plant species in the form of _______, with indirect effects benefiting a _______ of one of the plants.

The studies by Powers and colleagues of northern California river ecosystems showed

Suppose you wanted to determine whether you had adequately sampled the species richness of a given community. Which of the following results would most likely lead to the conclusion that more sampling was needed to assess the species richness?

What is the fundamental distinction between a competitive network and a competitive hierarchy?

In the classic trophic cascade, sea otters feed on sea urchins, which in turn feed on kelp. Via indirect effects, a reduction in kelp abundance would likely _______ the abundance of sea otters. A reduction in sea otter abundance would likely _______ the abundance of kelp.