One of the best books I’ve read this year, it talks about the new science of ancient DNA and how it acts as a tool to see deep into the past of our species. From this we learn many things such as the fact that human migrations have defined our past and the true way to think about our ancestors would be limited by both space (where your ancestors lived) and how far in the past you’re considering i.e. time (as it gets harder to move back across time because of intermixing due to migrations). One other cool thing I learnt was the numerous dead ends in the history of humanity. Not all groups of humanity intermix and some replace others. It seems we have a lot of groups who have no descendants today. It’s entirely possible for them to inhabit large contiguous regions for thousands of years and yet be replaced by other groups in a comparatively short span of time.
Another interesting subject was the inequality between men and women captured in DNA. TLDR; being that there are many examples of women from lower status groups who mated with men from higher status groups for multiple generations (could be choice/coercion). One example was Latin America where about 90% of the mitochondrial ancestry (i.e. maternal ancestry) was native to the continent while about 90% of the Y-chromosomal ancestry (paternal ancestry) was from Europe.
Yet another controversial subject was the caste inequality captured in DNA. From what we understand, the peopling of India involved ancestry from 3 groups: The native hunter-gatherers of the subcontinent, Iranian farmer groups, and the Yamnaya culture (from central Eurasia). It seems that there is some inequality in the distribution of the Yamnaya Y-chromosome which is found in different proportions depending on your caste and region. As a general trend, upper castes and northern Indians tend to have a higher proportion of the Yamnaya Y-chromosome.
There’s a lot of other surprises too such as the parallel histories of the subcontinents of Europe and India in regards to the Yamnaya expansion, the possible geographic origin of the ancient Dravidian speakers etc, the (partly) multi-regional evolution of Humans, etc. All in all, a 5-star book.