Natality - Population Parameters and Regulation
Natality is the ability of a population to increase. Natality rate is equivalent to birth rate which means the production of new individuals by birth, hatching, germination, or fission. Maximum production of new individuals under ideal conditions of ecological and physiological factors is always theoretical and is called maximum natality. It is constant for a popula
tion. However, the actual increase in a population under specific environmental conditions is referred to as realised or ecological natality. This is not constant for a population and may vary with the size and composition of the population, i.e. the number of females in reproductive age at a particular time. It also varies with the physical environmental conditions of the habitat a population is acquiring. For example, the realised natality rate for the human population may be only one birth per five years per female in the child bearing ages, whereas the maximum natality rate for humans is one birth per nine to eleven months per female in child bearing ages.