BIOL 2260 Lecture Notes - Lecture 5: Exponential Growth, Red Grouse
5 Jul 2016
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Document Summary
It is possible, but not for long. Limit is food supply and shelter o. Human populations grow exponentially: average life expectancy and multiple offspring per generation cause increase. No population can increase without limit o. Population reaches equilibrium when the birth rate equals the death rate. This can happen in three scenarios (red = births, blue = deaths) This is known as density-dependence: rate changes with density (third graph) Modified to make population growth slow as you approach carrying capacity (k) Suitable for overlapping generations and when resources are finite. Limiting factor: any factor that affects population growth. N/k ratio: environmental resistance to population growth. Population control: intentional manipulation of population by humans. Population growth rate depends on population size o o. Population stops growing when it hits the carrying capacity (k) K/2 when the population growth stops growing exponentially. Regulating factor: any density-dependent factor that depresses population growth as density increases.
