BIOL 308 Lecture Notes - Lecture 2: Recurrence Relation, Doubling Time, Generation Time
Document Summary
Factors acting at the level of population itself (e. g. birth/death, immigration/emigration) Factors controlling the intrinsic rate: feedback loop in birth and death--larger population group grow faster. Works for pulsed events, a clear time frame (e. g. annual plants, deer reproduction season), "cohorts" A group of individuals start their life cycle at the same time. An iterative process (repetitive of the same process, e. g. doubling population): leads to a "geometric growth" (but on a graph, the lines are only visual guidance) Difference equation (only consider female, when the sex ratio is fixed in a population) Time as a exponent factor, the population growth for many generations. The initial time state is often set to 0 (naught) Can be used to infer the growth rate, if we know 2 points on the graph. Population growth has a unit, e. g. 2 per day. A feedback process--changes in the population depends on the size of population.
