Chapter 45 - Species Interactions and Communities

Question 1

The Niche

Answer 1

A species’ place in nature, determined by physical (abiotic) and biological (biotic) factors.

Question 2

Physical Habitat

Answer 2

Influenced by climate, soil chemistry.

Question 3

Ecological Role

Answer 3

Shaped by interactions with other species.

Question 4

Fundamental Niche

Answer 4

Full range of climate conditions and food resources a species can potentially live in.

Question 5

Realized Niche

Answer 5

Actual range of habitats occupied by a species.

Question 6

Evolutionary Influence

Answer 6

Niches are shaped by evolutionary history.

Question 7

Phylogenetic Niche Conservatism

Answer 7

Tendency of species to retain aspects of their ancestral niches.

Question 8

Related Species

Answer 8

Closely related species often occupy similar niches.

Question 9

Interaction Costs

Answer 9

loss of resources

Question 10

Interaction Benefits

Answer 10

increases in reproduction

Question 11

Antagonisms

Answer 11

Interactions where at least one participant loses more than it gains.

Question 12

Competition

Answer 12

Interaction where the use of a mutually needed resource by one individual or group lowers availability for another.

Question 13

Competitive Exclusion

Answer 13

Prevents two species from occupying the same niche at the same time.

Question 14

Resource Partitioning

Answer 14

Division of resources by different species in the same habitat to minimize competition.

Through evolution, diversification, behavioural shifts

Question 15

Antagonistic Interactions

Answer 15

Interactions where one species benefits at the expense of another.

Question 16

Predation

Answer 16

Predator consumes prey.

Question 17

Parasitism

Answer 17

One species lives in close association with another, gaining nutrition by consuming host tissues.

Question 18

Herbivory

Answer 18

Consumption of plant parts, benefiting herbivores and harming plants.

Question 19

Mutualism

Answer 19

Interactions between species that benefit both parties.

Question 20

Evolution of Mutualism

Answer 20

Mutualisms may evolve, increasing interdependence.

Question 21

Obligate Mutualism

Answer 21

One or both sides can’t survive without the other.

Question 22

Facultative Mutualism

Answer 22

One or both sides can survive without the other.

Question 23

Facultative to Obligate

Answer 23

Can become obligate when reinforced through natural selection.

Question 24

Symbiosis

Answer 24

Close interactions between species (either antagonism or mutualism) that evolved over very long periods.

Question 25

Commensalism

Answer 25

One partner is unaffected by the interaction.

Question 26

Facilitation

Answer 26

One species indirectly benefits another.

Question 27

Dynamic Interactions

Answer 27

The costs and benefits of species interactions can change over time.

Question 28

Community

Answer 28

The set of all populations of different species found in a given place at a given time.

Question 29

Biodiversity

Answer 29

Includes the number of species, variety of genes, cell types, metabolisms, life histories, phylogenetic groups, and communities.

Question 30

Species Richness

Answer 30

The number of species in an area.

Question 31

Keystone Species

Answer 31

Species that supports a community in ways disproportionate to their abundance or biomass.

Question 32

Disturbance

Answer 32

Can modify community composition.

Question 33

Succession

Answer 33

The process of species replacing each other in a predictable sequence.

Question 34

Primary Succession

Answer 34

Colonization of new uninhabited areas (e.g., following an ice age glacier exposure).

Question 35

Secondary Succession

Answer 35

Reestablishment of communities following a disturbance.

Question 36

Climax Community

Answer 36

Represents little further change in species composition.

Question 37

Colonization and extinction difference between small vs large islands

Answer 37

Large: more colonization + less extinction

small opposite