Lecture 18: How species compete for resources

Question 1

What effect dose competition have on each speices involved?

Answer 1

Negative for both sides

Question 2

What is Interspecific Competition?

Answer 2

Competition between individuals of

different species

Question 3

What is Intraspecific Competition?

Answer 3

Competition between individuals of the

same species

Question 4

What is the core concept around competition?

Answer 4

Resources limitations.

Question 5

What is Interference Competition?

Answer 5

direct aggressive
interaction between
individuals.

Question 6

What is Exploitative competition?

Answer 6

competition to secure

resources first.

Question 7

Is competition common?

Answer 7

Yes, Pretty common, but more so in plants

compared to animals.

Question 8

Why is competition so common? and why is it more common among plants?

Answer 8

1. Plants exist in higher densities than
   animals
2. Plants can’t really move out of the way

Question 9

What is the Competitive Exclusion Principle?

Answer 9

two species

with the same niche cannot co-exist indefinitely

Question 10

True or false:

Stable coexistence occurs often, and is common in nature.

Answer 10

False.

Stable coexistence rarely occurs. More likely
than not species will occupy different realized
niches, and sometimes if pressure is strong
enough, will alter the dimensions of the
fundamental niche

Question 11

When doesn’t competitive exclusion

occur?

Answer 11

When disease and predation are the biggest limiting factors.

or

in extreme, or highly variable environments (like lakes)

Question 12

What happens when two plants who can both occupy acidic and basic soil are placed in the same environment?

Answer 12

One will dominate the acidic soils and the other will dominate the basic soil.

Question 13

What is Character Displacement?

Answer 13

Changes in the physical
characteristics of a
species’ population as
a consequence of
natural selection for
reduced interspecific
competition

Question 14

What is Character Displacement?

Answer 14

Changes in the physical
characteristics of a
species’ population as
a consequence of
natural selection for
reduced interspecific
competition

Question 15

What is the Evidence for Competition in Natural

Systems: Self-thinning in plants.

Answer 15

Plants will initially grow in high density, but will thin out as each plant gets bigger and occupies a greater portion of the landscape.

Question 16

What is the Evidence for Competition in Natural

Systems: Song Sparrow Territories

Answer 16

Song sparrow males come in two main varieties:

Territorial males that make nests and occupy a certain area and a already constructed nest.

Floater males that attempt to occupy the already made nests of the very old and young Territorial males