BIOL 226 Lecture Notes - Lecture 14: Starfish, Carrying Capacity, Semelparity And Iteroparity
Biol226-Ch 53
Population Ecology
Population: a group of individuals of the same species living in the same general area.
o Rely on same recourse
o Influenced by similar environmental factors
o Interact and breed
o Defined by boundaries and size
Density and dispersion
Density: population is the number of individuals per unit area of volume
o Needs total count
o Rarely possible
Dispersion: pattern of spacing among individual within the boundaries of the population
Processes that add to population:
1. Immigration: Influx of new individuals from other area
2. Birth
Processes that remove from population:
1. Death
2. Emigration: movement of individuals out of a population and into other location
Pattern of dispersion:
1. Clumped:
sea star group together where food is abundant
Most common
Plants and fungi
Insects
Effective for predation and defense
2. Uniform: Nesting albatrosses exhibit uniform spacing, maintained by aggressive interactions
between neighbors
Direct interaction between individuals
Territoriality in animals ; defense of bounded physical space against encroachment by other
individuals
Document Summary
Population: a group of individuals of the same species living in the same general area: rely on same recourse. Interact and breed: defined by boundaries and size. Density: population is the number of individuals per unit area of volume: needs total count, rarely possible. Dispersion: pattern of spacing among individual within the boundaries of the population. Processes that add to population: immigration: influx of new individuals from other area, birth. Processes that remove from population: death, emigration: movement of individuals out of a population and into other location. Pattern of dispersion: clumped: sea star group together where food is abundant. Insects: uniform: nesting albatrosses exhibit uniform spacing, maintained by aggressive interactions between neighbors. Territoriality in animals ; defense of bounded physical space against encroachment by other individuals. Result of antagonistic behavior like territoriality: random: dandelions grow from windblown seeds that land at random and later germinate. Position of individuals is independent of others.