The measure of the number variety and amp variability of living organisms in an ecosystem is called biodiversity.

Here's a breakdown:

* Variety: This refers to the number of different species present in the ecosystem. This is often referred to as species richness.

* Variability: This refers to the genetic diversity within each species, as well as the variability in the abundance of each species.

Therefore, biodiversity encompasses both species richness and genetic diversity.

Let me know if you'd like to know more about biodiversity or its importance!