system
Given the following post, respond as if you're commenting on Reddit:
human
[All DC] Why are Kryptonians, and lots of other aliens, so similar to humans?

Some can even breed with us, apparently! What's up with that?

Even alien robots, like the Manhunters and Brainiacs, seem to look a lot like we do. I think pretty much every hero in the Justice League can pass for human. Even the gods - and New Gods, and Kryptonian Gods, and Old Gods - that humanity knows of seem pretty much human; and I don't *think* they can shapeshift, necessarily, right?

What gives? Has something been seeding the universe(s) with near-human life?
gpt
After the universe was created the White Life Entity cocooned itself inside of the Earth, and life originated out from this point carrying with it some sort of base template - just at different rates of germination. The further the planet from Earth, the less 'human' - like the species. 

Best in universe answer I've got.