One by Powers.
I believe this one is too, though it’s more realistic than his usual.
This one by Robert Stanley gives Tarzan too perfect a hairstyle. They were modeling him on screen Tarzan Johnny Weismuller.
Y the Last Man apparently had a predecessor. Art is uncredited; I’ll bet the story is a lot more sexist too.
Another uncredited cover. I like the look.
I don’t have credits for this one either, but it looks interesting.
#SFWApro. All rights to images remain with current holders.
Fraser Sherman's Blog 
Nice blog