Populations - Community Evolution

Question 1

What may allow predator coexistence?

Answer 1

Niche differentiation, evolutionary forces driving competition avoidance.

Question 2

Competition varies with…

Answer 2

Taxon, habitat and trophic level

Question 3

How does interspecific competition influence community structure>

Answer 3

Niche differentation by comeptito
Character displacement

Question 4

How does niche differentiation express mostly?

Answer 4

Resource use, within a single habitat or microhabitats

Question 5

Niche Complementarity

Answer 5

Is where coexisting speceis use different forms of a resource

Question 6

Guild

Answer 6

A group of species exploiting the same resource, or exploit different resources in related ways

Question 7

Example of a guild…

Answer 7

Tropical borneo trees with different light tolerances differentiating along soil gradients based on nutrition.

Question 8

Unified Neutral Theory

Answer 8

Explains diversity and relative abundance of species in ecological communities

Question 9

Theoretical situation of unified neutral theory…

Answer 9

A local communtiy of interest within a metacommunity, providing a mix of well-sourced immigratns, containing fixed number of individuals(one dies-one born)

Question 10

Unified Theory population migration…

Answer 10

Depends on relative spatial distributions not on individuals characterisitscs..

Question 11

Unified Theory metacommunity migration…

Answer 11

Driven by random death and birth except immigration in the form of speciation in this case

Question 12

Importance of unified neutral theory despite unrealism?

Answer 12

Allow outlook of a world of which this were the case allowing interpretations of deviations of particular characteritis.

Question 13

Species Abundance Distribution

Answer 13

Describes the full distribution of commonness and rarity in ecological systems.

Question 14

Hutchinsons rule

Answer 14

This is the ratio of size differences between simialr species when they are living together as compared to when they are isolated

Question 15

Theory of Limiting Similarity

Answer 15

States that coexistence between species is more limited by competitive exclusion when species share niche properties.

Question 16

Example of hutchinsons rule…

Answer 16

Different species may consume different size prey, thus niche differentiation manifesting as morphological differences.

Question 17

Null Models

Answer 17

Are a random object that match on specific object in some of its features

Question 18

Evidence for interspecific competition…

Answer 18

Distribution patterns - (memebrs mutually exclusive but distributions so any one islands supports only one of the species

Question 19

Null model for interspecific competition….

Answer 19

Comapre patterns of species co-occurences at a locations with what would be expected if each species were distributed at random with excess of negative associations.

Question 20

Intransitive Competition

Answer 20

Where there is no single best competitor

Question 21

Intransitive Competition

Answer 21

Just because species A outcompetes B and B outcompetes C, does not mean A outcompetes C

Question 22

Example of outcompetition in Intransitive?

Answer 22

Allelechemicals.

Question 23

Importance of Intransitive Competition in structure…

Answer 23

Allowing co-existence as not one species can out compete all others

Question 24

Geometries of predation interacitons…

Answer 24

A diamond shape module where preadtor preys on two prey species, also sharing a common resource.

Question 25

Exampel of predator diamond module?

Answer 25

Omnivores preying on more than one of the lower trophic levels, maybe linked by predator-prey interactions.

Question 26

Most common effect of predation on structure?

Answer 26

Removal of prey

Question 27

Example of predation effect on structure...

Answer 27

Parasitism of endemic bird fauna on Hawaiian islands, attributed partly to bird pathogens

Question 28

Predator-Mediated Coexistence

Answer 28

The increase of species diversity of by a predator in comeptitve communties.

Question 29

Janzen-Connell Hypothesis

Answer 29

An explanation for the maintenance of tree species biodiversity in tropical rainforest.

Question 30

Distance Reponsive Predator

Answer 30

These lower seed/seedling survival or growth near adults of their main host.

Question 31

What is JC hypothesis a function of?

Answer 31

Host-specific predation(herbivory, pathogens) making areas near parent trees inhospitable for survival of seedlings.

Question 32

What drives JC hypothesis?

Answer 32

Higher prey densities promoting higher predation.

Question 33

When might parasite mediated coexistence occur?

Answer 33

Infection of multiple species where the superior competitior is differentially affected, allowing coexistence.

Question 34

Example of parasite-mediated coexistence?

Answer 34

Red Squirrels and Grey infection by parapox viruse

Question 35

What does predation effects on community depend on?

Answer 35

Strenghts o the links

Question 36

Stress-Gradient Hypothesis

Answer 36

Says that psoitve interactiosn are more commonly distsributed in harsher communities due to that being the most likely way to survive.

Question 37

Reasoning behind stress-gradient hypothesis...

Answer 37

Unproductive low resource envrionemtns more facilitation.

Question 38

A caveat in stress-gradient hypothesis...

Answer 38

Nurse species providing shade will out-compete for water levels