Population Ecology Dynamics

A population is a group of individual species that all reside in the same general area. These individuals rely on each other for resources because the same resources are used by every member of the group. Populations evolve for time due to natural selection favoring heritable traits within the group. Different populations of a single species may be isolated due to geographic barriers which causes exchanging materials only rarely. Members of a population typically breed with one another and this on average are more closely related to each other than to members of other populations.

A gene pool characterizes a population’s genetic makeup by showing the alleles that are present within the population. If only one allele is exists within a population is said to be fixed in the gene pool. Each allele frequency has a frequency in the population. If there are no differences within the population we can conclude that the real population is evolving. The gene pool of population that is not evolving can be described by the Hardy-Weinberg principle. This states that the frequencies of alleles and genotypes in a population will remain constant from generation to generation provided that only Mendelian segregation and recombination of alleles are at work, these gene pools is said to be in Hardy-Weinberg Equilibrium.

In order to study the relationship between population and the environment there is a separate field of study called population ecology. Within this field is population dynamics, which is the study of long and short term changes in the size and age of a population. This is done by correlating the birth rates, death rates, immigration, and emigration and how these factors affect a population. Population dynamics is based on three fundamental characteristics, density, dispersion, and demographics.

Density is the number of individuals per unit are or volume. Different patterns affect the density of a population. Additions to a population occur...