Species Diversity and all that stuffs.

Species, the number of different species and the amount of inidivduals within that species within a community.

Counting a species is the simplest way of measuring diversity, the problem is, using this method, the number of indivduals aren't taken into account.

Standard Deviation takes into account both the number of speicies, and the amount of indiviuals within that species.

If it is a high diversity, it is assumed that there is a stable community, and the living community is dominant, whereas, with low diversity, the community is unstable, and environmental conditions dominate.

We can asess Biodiversity Index (doing that standard deviation thingy.), by comparing between different habitats, asessing the affect of environment change on the biodiversity index of a community of organisms found in a particular habitat. From this, you can asess how stable or resistant they are to envionmental change. The greater the diversity, the greater the chance of a species being able to adapt to environment change.