Evolution - where does genetic diversity come from?

Mutation is one element of diversity, but it's probably not the major contributor at this point in our evolution. Simple mixing of genetic material through breeding, and expansion of populations into different areas have resulted in genetic diversity.

Most recently, humanity squeezed through the genetic bottleneck caused by the Toba eruption and it shows up in our genes. But we've probably squeezed through other bottlenecks before (at many stages of our evolution).

I guess that must have answered the question

Reasonable Answer--however chaos affects any complex system.

Chaos does not mean unbridled random mutation, chaos presents bounds. The extremes of chaos are prone to 'not be selected', many times by spontaneous rejection. Chaos means within bounds.

In lieu of modern medicine would diabetes be desirable? Wouldn't that depend upon the diet? And agriculture? Doesnt chaos have an influence here too?

Maybe if mutation is random then anything can happen anytime, but it isn't mutation is chaotic, not random.

Genetic speciation, to me implies isolation with accumulation of chaos over many generations.

Rap