Final answer:
Effective population size is a measure of the genetic diversity and viability of a population. It takes into account factors such as sex ratio, breeding patterns, and genetic drift. A small population with a low effective population size is more vulnerable to inbreeding and the loss of genetic variation.
Step-by-step explanation:
Effective population size is a measure of the genetic diversity and viability of a population. It refers to the number of individuals in a population that contribute genetically to the next generation. While the total population size is important, the effective population size takes into account factors such as sex ratio, breeding patterns, and genetic drift, which can impact the population's genetic health and adaptability. For example, a small population with a low effective population size is more vulnerable to inbreeding, genetic diseases, and the loss of genetic variation, which can decrease the population's ability to adapt to changing environments.