Population and Community Ecology Flashcards Preview

Biology of Mammals Lecture > Population and Community Ecology > Flashcards

Flashcards in Population and Community Ecology Deck (54)
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1
Q

What are the 5 different scopes of ecological research?

A
  1. global ecology
  2. landscape ecology
  3. ecosystem ecology
  4. community ecology
  5. population ecology
2
Q

How do community and population ecology differ?

A

Community - Interspecific

Pop - intraspecific

3
Q

What factors influence the distribution of a species?

A
  • dispersion/reproduction
  • abiotic factors (climate-light, fire, moisture, temp; salinity, o2)
  • biotic (predation, herbivory, competition, pathogens, disease)
4
Q

Define population

inter or intra specific?

A

group of organisms of the same species occupying a particular space at the same time.
genetic and ecological units in which a species’ members interact with one another.
Intra

5
Q

Define metapopulation

A

spatially separated, disjunct population which is distributed in patches across a heterogeneous landscape and interconnected by immigration (dispersal).

6
Q

By which mechanism are meta metapopulations connected?

A

dispersal

7
Q

What are advantages are dispersal?

A
  1. range expansion
  2. increased gene flow
  3. inbreeding avoidance
  4. reduced resource competition
8
Q

What are 3 patterns of dispersal?

A
  1. natal dispersal
  2. presaturation dispersal
  3. saturation dispersal
9
Q

What conditions affect the decision/ability to disperse?

A

age
condition
carrying capacity reached?
despite dependent/independent

10
Q

Describe natal dispersion

- who is this most common with in mammals?

A

The dispersion from birth place before the first breeding/before sexual maturity.
in mammals - usually males disperse

11
Q

Describe presaturation dispersal

A

animals in good condition
dispersal before the carrying capacity is reached
density independent

12
Q

Describe saturation dispersal

A

animals in poor condition
young/small
carrying capacity has been reached or exceeded
density dependent

13
Q

Dispersal is from ____ to _____ - _____ filled by _______

A

Dispersal is from source to a sink- empty habitat filled by immigration

14
Q

Have you done the required reading on UMLearn?

- determinants of habitat selection

A

Yes

15
Q

What are the determinants of habitat selection?

A

Genees and environment

Tradition

16
Q

What are properties of populations that help in measuring them?

A
density 
dispersion
sex ratios
age structure
mortality
natality
17
Q

How is density used to measure a population?

A

1 - count all individuals in a population
2 - estimate using sampling
3 - mark-recapture method depends on likelihood of recapturing the same individual

18
Q

Define density

A

number of organisms occupying a defined unit of space

19
Q

Define crude density

A

of individuals per unit area

20
Q

Define ecological density

A

measured in terms of useable habitat

rarely estimated - very difficult to measure what portion of habitat represent living space

21
Q

List 3 patterns of spatial dispersion.

What are they strongly influenced by?

A
  1. uniform
  2. random
  3. clumped
    - strongly influenced by landscape and interactions among members of the population
22
Q

What type of dispersion are the most even? why?

A

uniform - infraspecific comp.

(ex. territoriality)

23
Q

Define random dispersion

A

position of each individual is independent of others or the occupation of each is equally likely

24
Q

is random dispersion common or rare? when does it occur?

A

rare!
envr uniform
resources equally available all year
interactions among members of pop produce no patterns of attraction or avoidance

25
Q

what is the most common type of distribution pattern?

A

clumped

  • habitat differences
  • daily and seasonal changes
  • reproductive patterns and social behaviour
26
Q

What are some reasons that clumped distribution patterns can occur?

A

poor dispersal capability of young
patchy distribution of resources
social organization

27
Q

Define sex ratios

A

proportion of males to females - 1:1 in most sexually reproducing organisms

28
Q

1degree sex ratio

A

ratio at conception

29
Q

2degree sex ratio

A

ratio at birth

- usually weighted towards males in mammals

30
Q

Demographics

A

population dynamics

31
Q

what is a life table?

what can it be used for?

A

an age-specific summary of the survival pattern of a population.

producing survivorship curves

32
Q

Describe exponential growth model

A

uncontrolled growth
applicable to only initial growth after colonization of an unexploited habitat
not biologically realistic or sustainable

33
Q

Two examples of exponential growth

A

St Paul reindeer herd

Rabbits

34
Q

Describe the logistic growth model

A

idealized model of growth, slowed by limiting environmental factors
reach K - carrying capacity

35
Q

give two examples and boom and bust cycles

A

hares and lynx

snowy owls and lemmings

36
Q

give two examples and boom and bust cycles

A

hares and lynx

snowy owls and lemmings

37
Q

What is Life History and what do these traits include?

A
series of events from birth to reproduction, to death
- age @ first repro.
- freq. of repro.
- # offspring
amount of parental care given
energy cost of repro.
38
Q

What are the 2 major life history strategies?

A

r-selection

k-selection

39
Q

Describe r-selection

A

“live fast, die young”

  • reach sexual maturity early
  • large # offspring
  • litte/no parental care
  • generally short lived
40
Q

Describe k - selection

A

“live long and prosper”

  • reach sexual maturity late
  • small # offspring
  • parental care
  • generally long-lived
41
Q

What are r-selected species usually limited by? What about k-selected species?

A

r = density-independent factors
–> can easily colonize new habitats
k= density-dependent factors

42
Q

When is population ecology more important?

A

applied research

  • endangered species
  • manage wildlife populations
  • human pop. growth
  • SARA
43
Q

What are the 2 steps to in the SARA process?

A
  1. scientific evaluation

2. listing by government

44
Q

define mutualism

A

both organisms benefit

45
Q

define commensalism

A

one benefits, other with no loss/no gain

46
Q

define amensalism

A

one no effect, one negative

47
Q

how could a community be controlled bottom-up?

A

nutrients

48
Q

how could a community be controlled top-down?

A

predators

49
Q

how does production efficiency range between birds/mammals, fish, and insects?

A
birds/mammals = 1-3% (endothermy)
fish = 10%
insects = 40%+
50
Q

required reading on bison??

A

Yes

51
Q

how are bisons suggestion to shift ecosystem functions?

A

graze so intensely they they freeze plants in early spring for weeks at a time, preventing them from maturing. This forces them to continuously produce young shoots

  • increases nutrients in plants by 50-90% by end of summer
  • extra food
  • prolongs growing season
  • accelerates growth
52
Q

What are properties of a population

A
density 
dispersion
sex ratio
age structure
mortality 
natality
53
Q

What are some reasons for a clumped distribution?

A

poor dispersion of young
patchy distribution of resources
social organization

54
Q

Example of a mammal discussed in class that displayed exponential growth?

A

St. Paul Reindeer