Topic 7A: Populations - Distribution and Abundance

Question 1

Commonness

Answer 1

‘how common the species or organism is’

Question 2

Density

Answer 2

the number of individuals in a population per unit area

Question 3

Dispersal (small and large scale)

Answer 3

• affects the local distribution - potentially geographic
• decreases or increases local population density

Question 4

Clumped Distribution

Answer 4

one in which individuals in a population have a much higher probability of being found in some areas than in others; individuals are aggregated rather than dispersed.

Question 5

Random Distribution

Answer 5

one in which individuals within a population have an equal chance of living anywhere within an area

Question 6

Regular Distribution

Answer 6

one in which individuals in a population are uniformly spaced

Question 7

Fundamental Niche

Answer 7

the physical conditions under which a species might live, in the absence of interactions with other species

Question 8

Geographic vs local range of species

Answer 8

a species range is the area where a particular species can be found during its lifetime. Species range includes areas where individuals or communities may migrate or hibernate. Every living species on the plant has its own unique geographic range.

Question 9

Habitat Tolerance

Answer 9

Species have tolerance ranges for abiotic environmental conditions. They can tolerate (or survive within) a certain range of a particular factor, but cannot survive if there is too much or too little of the factor

Question 10

Metapopulation

Answer 10

a group of subpopulations living in separate locations with active exchange of individuals among subpopulations

Question 11

Numerical Responses

Answer 11

changes in the density of a predator population in response to increased prey density

Question 12

Population

Answer 12

a group of potentially interbreeding individuals of a single species inhabiting a specific area

Question 13

Range Expansion

Answer 13

Range expansion is how invasive species spread and how species track habitats shifting from climate chance.

Question 14

Rarity

Answer 14

used to describe low abundance, restricted range size or habitat specificity of a species

Question 15

Spatial Extent

Answer 15

Spatial Extent can generate spatial structure, in which individuals interact more intensely with neighbours than with more distant conspecifics, and it allows for environmental heterogeneity, in which habitat quality varies spatially.

Question 16

Species Range

Answer 16

is the area where a particular species can be found during its lifetime

Question 17

Biological Species