Chapter 17

Question 1

What is zonation?

Answer 1

Spatial changes in community structure. Each species has a competitive advantage in a different range of environments where resource availability differs.

Question 2

What is diffuse competition?

Answer 2

It describes the total competitive effects of a number of interspecific competitors.

Question 3

What does removal of a competitor result in when looking at diffuse competition?

Answer 3

Removal of a competitor will result in a response of the focal species (focal species = species being studied)

Question 4

What happens with removal of a competitor if competition only involves a single species? (Species A + focal species)

Answer 4

Removal of competitor results in a significant response of the focal species.
Focal species abundance and occupation in the environmental gradient increases

Question 5

What happens with removal of a competitor if competition involves multiple species? (species A-E + focal species)

Answer 5

Removal of 1 competitor results in a minimal response from the focal species.

Question 6

Removal of a single species has ________ effect, but removal of a group of species has a _________ effect,

Answer 6

little/limited
stronger

Question 7

What all does diffuse competition include (3)?

Answer 7

Competition
Predator-prey cycles
Pollination and seed dispersal

Question 8

How is diffuse competition and predator-prey cycles related?

Answer 8

Many different predators in a community use the same prey (resource), so they all play roles in prey population.

Question 9

How is pollination and seed dispersal and diffuse competition related?

Answer 9

A single plant species may require a variety of different animal species to successfully reproduce

Question 10

What is keystone predation?

Answer 10

Predator enhances the survival of one or more less competitive species by reducing the abundance of the more competitive species.

Question 11

What are 2 examples of keystone predation?

Answer 11

• Elephants eat and kill acacia trees, allowing for growth of shrubbery
• Starfish eat the fast-growing species, allowing for slower-growing species to mature

Question 12

What is bottom-up control?

Answer 12

The abundance of populations is controlled by the productivity/abundance of populations in the trophic level below them.

Question 13

What is top-down control?

Answer 13

The predator population control the abundance of prey species, which in turn influences the abundance of the predator’s food.