Global distribution of Inbreeding

An interesting map and the distribution and concentration seem highly plausible, although I am not sure what the criteria of inbreeding, relative to the percentages given, is. I assume it means marrying within a first or second cousin. It is also clear that some countries showing up as white on the map are doing so simply because there is no information. Most of South East Asia and sub-Saharan Africa fall into this category. I assume inbreeding in those areas is rather high.