Community Ecology 1 - Resources and Competition

Question 1

Resource

Answer 1

a thing or factor that causes POPULATION GROWTH and IS REDUCED BY USE
- CONTEXT: O2 and sunlight can still be a resource depending on the context

Question 2

Limiting Resource

Answer 2

resource that is reduced the most by use and thereby limits population growth first

Question 3

Niche

Answer 3

full range or RESOURCES that a species can use combined with the range of conditions a species can tolerate

Question 4

Fundamental Niche

Answer 4

the full set of all environmental conditions in which a species can survive and reproduce without any limiting factors
- what they can theoretically use

Question 5

Realized Niche

Answer 5

set of conditions actually used by the given species, after interactions with other species (predation + competition) have been taken into account and limiting factors are present
- what they can actually use

Question 6

Resource Partitioning

Answer 6

CLASS DEF: where REALIZED NICHES pack together for several SIMILAR SPECIES so they can COEXIST

process by which different species within an ecosystem divide up resources to avoid interspecific competition

Question 7

Competition in Ecosystems

Answer 7

Competition between resources is strongest where niches overlap - intense competition can lead to species using a realized niche smaller than its fundamental niche

Question 8

Ecological Interactions + Selection

Answer 8

These ecological interactions (resource partitioning) can exert strong selection pressure, that the trait to use the resource can adapt to a distinctly new character state
- Character Displacement
OR
- Competitive Exclusion
WILL OCCUR

Question 9

Character Displacement

Answer 9

an evolutionary ADAPTATION in a heritable trait, caused by RESOURCE PARTITIONING
- shift in trait value

Question 10

Competitive Exclusion

Answer 10

if the trait in question lacks enough heritable variation for character displacement to occur then:
- the inevitable elimination from a habitat of one or two different species with identical needs for resources

Question 11

Interspecific Competition

Answer 11

competition for resources that drives reductions in niche overlap
- has negative effects on both species in the interaction between it uses up ENERGY
- individuals from each species would have more success (less energy used) in the absence of the other species
- super common because resources are limited but necessary

LOSE-LOSE SITUATION

Question 12

Predation

Answer 12

predator-prey interactions; one species consuming the other

WIN-LOSE SITUATION

Question 13

Parasitism

Answer 13

parasite-host interactions; a species lives on or in another species that it harms over time, sometimes causing host death

WIN-LOSE SITUATION

Question 14

Herbivory

Answer 14

a grazer eats a plant

WIN-LOSE SITUATION

Question 15

Mutualism

Answer 15

both species benefit from the interaction
- EX: pollination

WIN-WIN SITUATION

Question 16

Commensalism

Answer 16

one species benefits from the close, prolonged interaction, while the other is not impacted or affected
- EX: birds resting in trees

WIN-UNAFFECTED SITUATION

Question 17

Amensalism

Answer 17

one organism inflicts harm without receiving any costs/benefits

LOSE-UNAFFECTED SITUATION

Question 18

Coexistence

Answer 18

where two species can be in the same place at the same time

Question 19

Competitive Exclusion

Answer 19

where the most successful species will out-compete the other to the point of elimination

Question 20

Resource Partitioning

Answer 20

where realized niches pack together for several species

Question 21

Character Displacement

Answer 21

an evolutionary adaptation in a heritable trait, caused by resource partitioning