The latest Nature has a paper on mapping endangered animal species in a couple of different groups and relating what might be called “extinction threat hotspots” to “biodiversity hotspots.” The paper is getting a lot of media attention, for example here and here. Perhaps not surprisingly, the two types of hotspots do not match up, so a focus solely on protecting biodiversity in the well-known global hotspots is perhaps not going to be as effective as one might wish. No word on whether someone is doing similar work on plants, but I wouldn’t be at all surprised if the results were to turn out similar. But what about crops? I can think up theoretical arguments why centres of genetic diversity of crops might also be at particular risk from genetic erosion, but as for empirical data the problem is that information on genetic erosion tends to be anecdotal and patchy.
Blind dates
According to this article, the number of date palms in Morocco has declined from 15 million at the end of the 19th century to 4.5 million now, mainly due to desertification. That has to have had some effect on genetic diversity, and I’m willing to bet there are data out there on the numbers of varieties at different times in the past.