Is it on the back of a turtle? And others

[supergee]

Guide to figuring out the age of an undated world map [XKCD]

Comments

[gingicat]

Did they give credit to Randall Monroe, who created that exact image?
https://xkcd.com/1688/

[supergee]

Not sure & I can't find it now, but I corrected it.

[weofodthignen]

What gingicat said.