the genetic variation present in a population or species. For example, the genetic diversity in the hundreds of varieties of potatoes can be seen by their differences in size, shape, color, taste and rate of growth.
Usually, the range of characteristics within a species which, over evolutionary time, allow that species to respond to new features of its environment; sometimes refers to the variety both within and across species in a given area, or even worldwide
The genetic variation that occurs within a population or species. For example, there are several different color dog whelk shells and ochre sea stars. See also biodiversity; compare ecosystem diversity, species diversity.
All of the genetic variation within a group. The genetic diversity of a species includes both genetic differences between individuals in a breeding population (=within-stock diversity) and genetic differences among different breeding populations (=among-stock diversity).
The variety of different genes occurring within a population or species. In most species, many different versions or "alleles" of a gene will exist in a population of different individuals. For example, in humans, everybody has a gene affecting eye colour, but the different versions of these genes give rise to variety in eye colour in the population.
The genetic diversity within a species is primarily the variety of populations that comprise it. Species reduced to a single population (like the California condor) generally contain less genetic diversity than those consisting of many populations.
Genetic diversity is a characteristic of ecosystems and gene pools that describes an attribute which is commonly held to be advantageous for survival -- that there are many different versions of otherwise similar organisms. For example, the Irish potato famine can be attributed in part to the fact that the genetic distance of all potatoes in the country was very low, making it easier for one virus to infect and kill much of the crop.