Great idea as a way to benefit readers and the author of the post.

The first ~half of the book (prehistory) was much better than the second. Even then, I recall the author missing some rather significant points.

For example, the hypothesis that megafauna die-offs were related to the appearance of humans minimized one of the biggest, non-human contributors - the recession of glaciers at the end of the last Ice Age (Pleistocene). The accompanying environmental dislocation is enough on its own to explain the extinction, but you'll find almost nothing about it in the book.

It's almost certainly no coincidence that the early phases of what we think of as civilization begin to appear very soon after the end of the last ice age. Yet the author seems to blithely skip over that looming detail as well.