Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

BDE 214 A1T2 > 4 - Community assembly (1) > Flashcards

4 - Community assembly (1) Flashcards

1
Q

‘Assembly’

A

World -> Continent / region (Historical/ biogeographic filter) -> Biome / Habitat (Habitat/ environmental filter) -> Community (Competition/ biotic filter)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Regional species pool

A

The set of species present in a region from which local communities are assembled

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Theory of Island biogeography

A

MacArthur and Wilson 1963
- There will be an equilibrial point where immigration rate = extinction rate.
… an increase in island size will lower extinction curves,
a decrease in distance between the island and the source region will raise immigration curves.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Wallace line

A

Hypothetical boundary that separates the highly distinctive faunas of the Asian and Australian biogeographic regions and passes between the islands of Bali and Lombok in Indonesia, between Borneo and Sulawesi, and between the Philippines and the Moluccas.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Floral kingdoms (Good 1947)

A
  1. Boreal or Holarctic,
  2. Neotropical,
  3. Paleotropical,
  4. South African,
  5. Australian,
  6. Antarctic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Zoogeographic realms

A
  1. Palaearctic,
  2. Australasian,
  3. Nearctic and
  4. Neotropical.
  5. Oriental Realm
  6. Ethiopian Realm
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Zoogeographical realm meaning

A

A sub-division of the Earth having a unique fauna, i.e. species that are found only in that area.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Niche

A

Part of the environment that a species can occupy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

The Grinnellian niche (1924)

A

…the ultimate distributional unit, within which each
species is held by its structural and instinctive limitations”.
———————————————————————————————-
Every species has physiological, morphological, behavioural profile that make it
suitable to occupy a particular space offered by nature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

African phytochoria (Takhtajan 1978)

A

Phytochoria are defined as areas possessing a large number of endemic taxa.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Mesic fynbos

A

Grows in areas with relatively higher moisture levels or more moderate environmental conditions.
- more rainfall or have better water retention in the soil.
- diverse array of plant species, including various shrubs, small trees, and flowering plants (lush and densely vegetated)
Jonkershoek

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Xeric fynbos

A

Grows in areas characterized by lower moisture levels or drier environmental conditions.
- less rainfall, have poorer soil water retention, or higher evaporation rates
- drought-resistant traits - succulence or small, leathery leaves. - less dense and more scattered
Cederberg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Species pool

A

A set of species available to colonize a local community.
Originates through evolutionary / biogeographical process and adaptation to macro-habitats

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Competition

A

A mutually negative interaction among species at the same trophic level directly or indirectly resulting in reduced fitness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Exploitative competition

A

Depletion of a limiting resource

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Interference competition

A

Exclusion by aggressive interactions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Apparent competition

A

Reduction of a species through influence of a second species on predation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Lotka-Volterra model

A

Explores how competition influences the abundance of two competing species

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

When α, β < 1

A

interspecific competition is
weaker than intraspecific competition
STABLE CO-EXISTANCE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

When α, β > 1

A

Interspecific competition is
stronger than intraspecific competition
COMPETITIVE EXLUSION of weaker competitor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Competitive exclusion principle – Georgii Gause 1936

A

Two species with identical niches cannot coexist indefinitely/ two species must differ in some
aspect of their niche in order to
coexist

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

The Eltonian niche (1927)

A

…. the status of an animal in its community, to indicate what it is doing and not merely what it looks like”
NICHE = functional role of species in a community

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Charles Elton niche def

A

Niche is a property of the species, and not the environment.
Defined by biotic interactions and resource-consumer dynamics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

The Hutchinsonian niche (1957)

A

… an n-dimensional hypervolume, enclosing the complete range of conditions under which an organism can reproduce itself”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

G. Evelyn Hutchinson niche def

A

physical and biological conditions needed to maintain a stable
population size

23
Q

Realised niche

A

ecological niche a species actually occupies in the presence of other species (and dispersal limitation)

24
Q

Fundamental niche

A

ecological niche a species could occupy in the absence of other species (and dispersal limitation)

25
Q

“Paradox of the plankton” Hutchinson (1961)

A

Asks why well-mixed pelagic environments of lakes or oceans maintain a large number of phytoplankton species (tens or hundreds), even though the component species largely require the same resources.

26
Q

Predictions

A
  1. Interspecific competition should be common
  2. Potential competitors in a community should exhibit differentiation of their realized
    niches
  3. Niche differentiation should manifest as morphological (functional trait) differentiation
    of coexisting species
  4. Niche / functional trait differences between populations of a species living alone and
    those coexisting with a competitor
  5. ) Competitors should have negatively associated distributions (ie species that are too
    similar should not co-occur)
27
Q

Resource partitioning

A

When different organisms within one ecosystem split up an area so that they will not compete for the same resources = have a special adaptation.

28
Q

Niche partitioning examples

A
  1. Warbler species - McArthur 1958
  2. Anemones & fish - Elliot and Mariscal 2001
  3. Carex plant - Augustyn, Anderson, Ellis 2016
29
Q

Functional trait

A

Morphological, biochemical, physiological, structural, phenological, or behavioral characteristics that are expressed in phenotypes of individual organisms and are considered relevant to the response of such organisms to the environment and/or their effects on ecosystem properties.

30
Q

Principle of limiting similarity

A

The theory of limiting similarity, stating that coexistence between species is more limited by competitive exclusion when species share niche properties.

31
Q

How different do species need to be to coexist, or is there a limit to similarity of competitors for coexistence?

A
32
Q

CHARACTER DISPLACEMENT

A

Describes an evolutionary change that occurs when two similar species inhabit the same environment. Under such conditions, natural selection favors a divergence in the characters–morphology, ecology, behavior, or physiology–of the organisms.

33
Q

Checkerboard distributions

A

A pair of species with exclusive island-by-island distributions, but that have overlapping geographical ranges
- “Checkerboard rule” - some pairs of species never coexist either by themselves or as part of a larger
combination (Jared Diamond 1975)

34
Q

Mutualism

A

A two-species interaction that confers survival and/or reproductive benefits to both partners

35
Q

Obligate mutualisms

A

Species specific, entirely dependent on one another

36
Q

Facultative mutualisms

A

Generalised, could survive without each other

37
Q

Fig-fig wasp mutualism

A

Most fig trees are pollinated by the fig wasps (females) , and in these cases, the pollinating fig wasps are completely dependent on the fig for sustenance and reproduction, the ingredients for a strong obligate mutualism that directly impacts reproductive success.

38
Q

Facilitation

A

Modification of some component of the abiotic or biotic environment by one organism that enhances colonization, recruitment, and establishment of another (Nurse plant syndrome)

39
Q

Nurse plant syndrome (Franco & Nobel 1989)

A

Takes place when plant species shelter seedlings, young and/or adult individuals of other species through their ontogeny. The nurse-plant might then enhance fitness, survival and/or growth of associated species

40
Q

Ontogeny

A

the development of an individual organism or anatomical or behavioural feature from the earliest stage to maturity.

41
Q

Exploitative interactions

A

Interactions where one species benefits at a cost to the
other

42
Q

Examples of exploitative interactions

A
  1. Predation
  2. Herbivory
  3. Parasitism
43
Q

Density-dependent predation/parasitism/pathogen attack

A

increased rate when prey are abundant

44
Q

Janzen-Connell Hypothesis (1970-1971)

A

Provides one mechanism, suggesting that host-specific natural enemies are concentrated where their host plant species occur at high densities suppressing recruitment and survival of their host plants (negative conspecific density dependence)

45
Q

Why do species need to occupy different realized niches to coexist?

A

This ensures that intraspecific competition exerts stronger control on populations than interspecific competition – allowing coexistence)

46
Q

Intra vs interspecific competition

A

Intraspecific - occurs between members of the same species & improves species’ adaptations. Interspecific - occurs between members of different species & may lead to one species going extinct or both becoming more specialized

47
Q

How does a community get assembled from the species pool?

A
48
Q

Stabilizing mechanisms

A

reduce the influence of competition (ie prevent competitive exclusion)

49
Q

Determinism

A

They have different dispersal traits / modes

50
Q

Stochasticity

A

Stochasticity of dispersal

51
Q

Why can’t all species in the species pool can reach the local community

A
  • because they have different dispersal traits / modes (determinism)
    -because of the stochasticity of dispersal (stochasticity)
52
Q

So, how dispersal limited are communities?

A
53
Q

Dynamics of the local community are driven by

A
  • speciation/extinction in the species pool
  • dispersal from the species pool to the community
  • competition between equivalent species
54
Q

Non-equilibrial view

A

Nonequilibrium ecology asserts that ecosystems under disturbance pressure have a limited capacity for autogenic balancing and reach thresholds at which the system shifts to an altered state
- competition-colonization balance

55
Q

Intermediate Disturbance Hypothesis (IDH)

A

Local species diversity is maximized when ecological disturbance is neither too rare nor too frequent.

56
Q

Storage effects

A

Buffers species against
competitive exclusion during
bad years, thus promoting coexistence.

57
Q

Storage examples

A
  1. Seed dormancy
  2. Longevity of adults
  3. Bulbs

BDE 214 A1T2 (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions