Biology 2483A Lecture : Ecology 10.docx
5 Dec 2013
School
Department
Course
Professor
Document Summary
The ways in which populations change in abundance over time. The number of individuals in a population can change from one time period to the next. Population size changes as a result of four processes: birth, death, immigration, and emigration. Nt+1=nt + b - d + i - e. E=number of emigrants between time t and time t+1 (in between one year and the. Populations exhibit a wide range of growth patterns. The four main patterns are exponential growth, logistic growth, population fluctuations, and regular population cycle. These four patterns are not mutually exclusive. A single population can experience each of them at different times. Population increases (or decreases) by a constant proportion at each point in time. N(t+1)= nt if reproduction occurs at discrete time periods. When conditions are favourable, a population can increase exponentially for a limited time.
