Describe two ways of measuring biodiversity. Explain the relationship between biodiversity and ecosystem stability. As part of your explanation, discuss how susceptibility to disease in agricultural crops and in isolated tribal human populations provides evidence that supports this idea. (5 points)

- Two predictors to measure biodiversity: Species Richness and Simpson's Index  

- Biodiversity increases ecosystem stability  

- It has been shown that natural ecosystems are more stable than monocultures, while isolated human populations are found in highly diverse ecosystems

Explanation:

Two major predictors to measure biodiversity are: 1-species richness and the 2-Simpson's index. The species richness is a count for the total number of the species in a given habitat and/or ecosystem; while Simpson's index is a similarity index that indicates the likelihood that two different individuals selected at random from a sample will belong to the same species, thereby also estimating the biodiversity of a habit and/or ecosystem. Simpson's index takes into consideration the number of species and the abundance of each species. Ecosystems with high diversity tend to be more stable and resilient than ecosystems with low diversity. Biodiversity increases ecosystem stability due to the species asynchrony, which is a strong driver capable of stabilizing multiple processes/functions in the ecosystems over time (e.g., the productivity of the ecosystems over time). In this regard, it has been shown that forests that are highly diverse in the number of species are more productive and stable under stress than monocultures (i.e., agricultural crops), while isolated human populations live in sustainable ecosystems, it is for that reasons that isolated tribes are only found in highly diverse ecosystems.