Demography
Demography = statistical study of populations; indicate factors affecting the population growth rate
Sex ratio: Number of births usually related to number of females, but not so closely related to number of males if females mate with more than one male; closely related in monogamous populations
Generation time: average interval between birth of an individual and birth of its offspring; generally larger size ? longer generation time
Cohort = group of individuals of the same age
Survivorship in dependence of age varies among species
Fecundity = number of offspring/time unit (year)