Civ,
I never heard of the HAB - I only pointed out (before the mention of the HAB) that to my knowledge the last time Antarctic coast was ice free was around 14 million years ago - a statement to which no one replied. I have recently read that some think the coast (or parts of it) might have been ice free as recently as 1 million years ago.
How did those maps come into existence? We will likely never know the origins that were likely lost in the Great Lisbon Quake in the 18th Century which destroyed the library where the Portuguese kept all their secret maps ... and perhaps the original sources of the maps we have today.
I only pinged you to the HAB reply because you'd been pinged to the earlier information.
Those 16th c maps don't show what they're purported (by some) to show, which is an ice-free Antarctica. None of the maps of the early "Age of Sail" can compare with modern maps, even for coastlines that were near to the homes of the mapmakers, much less the "here be dragons" ends of the Earth.
I'd agree that the permanent glaciation of Antarctica as we know it today is a bit more than two million years old, and arose as a consequence of the Eltanin impact. That is, perhaps coincidentally, about when our ancestors started their long hard climb.
I don't agree that it was ever Atlantis.