AP Biology Unit 8 Review-Ecology

[[@@Population Ecology@@[[

%%Population Growth%%

• Factors that affect population growth are: Age of reproductive maturity, number of offspring produced, frequency of reproduction, and survivorship of offspring to reproductive maturity
• Equation: dN = change in pop size, dt = change in time, B = Birth rate, D = death rate

^^dN/dt = B - D^^

%%Exponential Growth%%

• Sharp increase in population growth, occurs under ideal conditions w/ abundant resources
• Number of organisms added to each generation increases as the population grows
• More individuals are reproducing but amount of time it takes to produce offspring stays the same
• J CURVE!!

Equation: dN = change in pop size, dt = change in time, N = population size, r = maximum per capital growth rate of population

^^dN/dt = rN^^

%%Logistical Growth%%

• Growth starts slowly, then exponential growth, then stable maximum growth
• Carrying capacity: Max # of individuals envt can support

• Equation: dN = change in pop size, dt= change in time, N = pop size, K = carrying capacity, r = max per capital growth rate of pop

  ^^dN/dt = rN((K-N)/K)^^

%%Factors that limit population growth%%

• ^^Density-independent^^ factors include natural events such as wildfires, hurricanes, earthquakes, etc.
• ^^Density-dependent^^ factors depend on population density and include things like competition, disease, and predation