Population Growth and Regulation

Terms:
overlapping and nonoverlapping generations, iteroparous, semelparous, age structure, stable age distribution, cohort, life history table, survivorship curves, fecundity, net reproductive value (R_o), generation time (T), static or time-specific life table, r and K-selected species

age structure: The number of individuals in each age class in a population at one point in time.

cohort: All individuals of a population born in the same year.

fecundity: The average number of births per individual in a population, usually tracked through females only.

generation time (T): The average number of years for a female in a population to produce all her female offspring in life.

iteroparous: Species that breed two or more times in their life.

K-selected species: A long-lived species with high survivorship until late in life that produces low numbers of offspring every 1-2 yrs. 

life history table: A table that summarizes the demographic variables for a population, can be based on a cohort tracked through time or time-specific data.

net reproductive value (R_o): The average number of female offspring produced by each female in a population throughout their life.

nonoverlapping generations: When offspring reach breeding age after their parents have stopped breeding in their lives.

overlapping generations: When offspring reach breeding age while parents are still breeding.

r-selected species:  A species with small size, rapid growth, and that produces high numbers of offspring more than once per year.

semelparous: Species that breed only once in their lives.

stable age distribution: When the relative proportions of individuals in each age class of a population stays the same through time because the growth rate of each age class does not change.

static or time-specific life history table: A table that summarizes demographic data for a population based on the age structure of the population at one point in time.

survivorship curves: Plots that show the probability of survival with age in a population, usually depicted in three types: Type I, II, and III.