8.4 Population Dynamics Flashcards
1
Q
What are two factors that influence populations?
A
- natural selection and environmental factors
2
Q
What is life history?
A
The traits that affect an organism’s schedule of reproduction and survival
3
Q
What are three variables that affect life history?
A
- When reproduction begins
- How often the organism can reproduce
- The number of offspring produced per reproductive episode
4
Q
What is K-selection (density-dependent selection)?
A
- selection for life history traits that are sensitive to population density
5
Q
Where is k-selection (density-dependent selection) seen in?
A
High density populations that are close to carrying capacity (K)
6
Q
What is R-selected (density-independent selection)?
A
- selection for life history traits that maximize reproductive success
Note: humans fall under this cuz lower pop, no competition
7
Q
Where is R-Selected (density-independent selection) seen in?
A
Low density populations with little competition
8
Q
What is density-dependent regulation?
A
- As a population increases, factors can slow or stop growth by decreasing birth rate and increasing death rate
Ex. Competition, predation, toxic wastes, territoriality, diseases, intrinsic factors
9
Q
What are density-independent regulation?
A
- factors that exert their influence on population size, but birth/death rate if a population does not change
Ex. Weather, climate, natural disasters
