Chapter 20 Special interactions

Question 1

Type of interactions between individuals

Answer 1

Benefit (positive, +) individual has more offspring or survives longer (Increases population growth
Harm(negative, -) Individual has fewer offspring or dies sooner. Decrease population growth

Question 2

Preator/prey interactions ( +, -)

Answer 2

One individual benefits (predator, herbivore, pathogen/parasite) and other is harmed

Question 3

Mutualism (+,+)

Answer 3

Both individual benefit from the interaction

Question 4

Commensalism (+,0)

Answer 4

One individual benefits, other is unaffected

Question 5

Types of interactions between individuals

Answer 5

Benefit: individual has more offspring or survives longer increases population growth ( positive, +)

Harm(negative, -): individual has fewer offspring or dies sooner decreases population

Competition (-,-): Both individuals harmed by the interaction

Ammensalism (-,0): One individual harmed, the other unaffected

Question 6

Interspecific interactions affecting population regulation

Answer 6

Beneficial interactions can cause increase a species K
Harmful increase can reduce a species K or cause extinction

Can maintain or disrupt natural selection

Question 7

Self thinning in plants

Question 8

Competition Exclusion principle

Answer 8

Two species that use the same resources in the same way cannot co-exist. One will drive the other extinct.

Question 9

The R* rule

Answer 9

The species that can suppress the resource to lower equilibrium level R* will competitively exclude the other species

Question 10

Exclusion to the R* rule

Answer 10

This can happen when same-species by segregating themselves. However, combined population are less than total population of a habitat where the species is by itself.

Question 11

Niche Utilization curve

Answer 11

the frequency at which a species uses range of resource types (e.g. seeds of different size)
or the performance of a species (e.g. reproductive output) for a range of environmental conditions