Topic 14 Flashcards
Population
A group of individuals of the same species, occupying a given area at
the same time
Population Ecology
The study of a population in relation to their environment
How do biotic and abiotic factors influence the distribution and
abundance of populations
Density
* Distribution
* Vital statistics
* Size
* Age structure
Cohort
all individuals born at the same time
Life Tables
Study demography, vital statistics and change through time
Density Independent
Growth rate and density are independent of one another
Density-Dependent Factors
*Disease
* Competition for resources
* Predation/herbivory
* Waste
* Competition
Density-Independent Factors
*Weather
* Natural Disasters
* Seasonal changes
Logistic Population Growth
- Density-dependent population growth model
- Individual reproduction decreases as population size increases
- Carrying Capacity (K)
Allocation trade offs
- Parental investment vs. # of offspring
- Egg size vs. # of offspring
- Age of reproduction/death vs. # events
- Frequency of reproduction vs. # events
principle of allocation
Evolution will produce phenotypes that allocate limited resources
between competing physiological processes in such a way as to
maximize fitness
Reproductive Strategies
2 General Types
- Survival rate of offspring
- Likelihood adult will survive to reproduce again
Semelparous
- Reproduces once, usually produces many small offspring
- Favored in highly variable environments
Iteroparous
- Reproduces multiple times, often produced few large offspring each time
- Favored in stable environments
r selected traits
- Maximize growth
- Typically density-independent
- Operate at low densities
- Acts on populations in unstable environments
