The Hindustan Times had a nice short piece recently on the diversity of mango in India.
Students of the participating schools recorded over 200 varieties of mangoes from about 60 locations in the Western Ghats. A study of these varieties has been done by CEE with IISER, Pune, to understand how distinct these popular varieties are at the genetic level.
Having large varietal diversity in a crop makes it possible to choose or develop varieties that can withstand climate change impacts. Different varieties are able to tolerate drought, high rainfall or extreme heat conditions, or pest attacks.
I just wish I could get hold of a high quality version of the poster used to illustrate the article.