Chapter 11 Infraspecific Population Regulation Flashcards Preview

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Flashcards in Chapter 11 Infraspecific Population Regulation Deck (20)
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1
Q

Density Dependent Population Regulation

A

how higher densities naturally lead to less births (decreasing fecundity) and more deaths (increasing mortality), leads the populations to slow the rate of population growth

2
Q

Carrying Capacity (K)

A

maximum sustainable population size for the prevailing environment

3
Q

Logistic model of population growth (dN/dt = rN (1 - N/K))… implications of K? where is growth maximized?

A
  • maximizes growth rate of population at HALF the carrying capacity size (K/2)
  • at K, population growth is 0
4
Q

Competition

A

-OCCURS WHEN INDIVIDUALS USE A COMMON RESOURCE THAT IS IN SHORT SUPPLY RELATIVE TO THE NUMBER SEAKING IT

5
Q

Scramble Competition

A

when growth and reproduction are depressed . equally across individuals in a population as the intensity of the competition increases… !!!!!!!!not any advantages for some individuals over others!!

6
Q

Content Competition

A

when some individuals claim enough resources while denying others a share… some successful individuals do better than others

7
Q

Exploitation competition

A

individuals don’t interact with one another… zebras eating the grass in the savanna don’t directly influence eachother but end up overgrazing and causing less grass to be available for other individuals

8
Q

Interference Competition

A

denying other individuals access to the site and its resources (LIKE A BIRD DEFENDING ITS NEST DURING BREEDING SEASON)

9
Q

Density independent factors meaning

A

natural influences… like a drought or excessive flooding

10
Q

Density dependent growth meaning

A

inverse relationship between population density and growth… MORE DENSITY, LESS GROWTH

11
Q

Influence of competition on growth

A

Less growth if more competition

12
Q

Influence of competition on mortality rates/ survival rates

A

competition reduces survivial rates/ increases mortality rates

13
Q

self thinning

A

progressive decline in density and increase in biomass of remaining individuals caused by combined effects of density dependent mortality and growth within a apopulation…. AS POPULATION STARTS TO DECREASE, SIZE OF REMAINING INDIVIDUALS GOES UP… something like this

14
Q

Competition impact on reproduction

A

REDUCES REPRODUCTION… REDUCES FEDUNCITY… less resources for the population, less mass per individual, less babies for smaller animals

15
Q

Home range

A

area that an animal normally uses during a year

16
Q

How home range varies as a function of body size or trophnic group?

A
  • carnivores require a larger home range than herbivores and omnivores of the same size
  • bigger the body size, bigger the home range needs to be
17
Q

Territory

A

home range that is defended by an animal

18
Q

When there is an EXCESS of males and females of reproductive age unable to establish breeding territories…

A

the act of having territories would act as a density dependent regulator as reproduction would be limited.. but only if there is nowhere to have territory!

19
Q

Allee Effect

A

density dependent mechanism have also been identified that function to reduce birth and survival rates of populations with LOW DENSITIES

20
Q

Some examples of allee effect:

A
  • organisms having too small pop densities in an area nd thus not being able to reproduce decreasing birth rates
  • when a population is too small to sustain an effective herd or pack, the population may decline from increased mortality because of predation or starvation