I saw this on a young anthropologist’s Tumblr page this morning and really appreciated it. I could not find an author’s name to credit it properly so I hope someone can point me in the right direction. A pen name of XKCD was associated with it.
I like timelines when they are well done and this one packs a good deal of perspective and information into a fairly simple graphic. Read closely. I have “educated” folks argue that the data are not “real” or that this sort of fluxuation just happens all the time but unfortunately, they tend to come without any actual facts or knowledge of the subject. Do not get your science from an entertainment television channel!