Population Ecology Flashcards
Dispersal patterns
Dispersal patterns are the local densities of individuals within a population’s geographic range. Culmped, Uniform, and random.
What is the best sampling method for motile organisms?
Lincoln-Peterson Index based on capture, release, and recapture.
What are the best sampling methods for non-motile organisms (or limited motile organisms)
Transects (line): Used for larger organisms
Quadrats (boxes): Used for small-medium sized organisms.
Survivorship curve
A graph that shows The rate of survival of organisms at different ages.
What are the 3 types of survivorship curves?
Type I: High survival probability in early and mid-life, but low in later life. Usually present in organisms with fewer offspring with parental care.
Type II: Relatively consistent probability of survival in every stage of life.
Type III: Low survival probability in early life, high in middle to later life. Usually present in organisms with many offspring and little to no parental care.
What are the four factors that affect population growth?
Natality, Mortality, Immigration, and Emmigration
Density-independent factors
factors that affect natality and/or mortality regardless of the size of the population
- Ex. Natural disasters, climate events, etc.
Density-dependent factors (4)
factors whose impact on natality and/or mortality is directly related to the density of the population
1. increased competition
2. increased spread of disease
3. build-up of waste
4. increased preditation
What are the four types of population growth?
Positive exponential: an increase of a population Natality+Immigration»Mortality+Emmigration
Negative exponential: a decrease of a population Natality+Immigration«Mortality+Emmigration
Logistic: Represented by an increase in population size until it levels off at carrying capacity due to density-dependent factors
Population overshoot: Represented by a rapid increase of population followed by a crash in the population. Caused by the removal of a density-dependent factor.
What are some social factors affecting the human population?
Sanitation/health care
Culture/attitude
Age and sex distribution (the more young females in a population, the more the population can grow)
What are the limitations when determining the carrying capacity for humans on Earth?
Modern medicine and health care:
- allows us to live at a higher density without disease wiping us out
Natural Disasters:
- impacts more people because of the density of the population, and can impact the access to resources
Resource use:
- Mostly just the fact that resources are limited (in more developed areas more than non-developed areas) and that many aren’t renewable
Technology:
- Allows for technical solutions to problems
Technical solutions
Solutions that require only a change in equipment or protocol, and require little to no change in human values or behavior
What are the three main world views?
Anthropocentric: only humans have intrinsic value and they use other natural resources as tools
Animal rights: All sentient individuals have intrinsic value and are equal to humans. The rest of the natural world has instrumental value
Biocentric: All living organisms have intrinsic value. Abiotic nature has instrumental value
