The idea of Batman vs Superman: Superman, a god-like being, whose actions were beyond normal human’s understandability, is an alien from Krypton.
But is it true that Superman is extraterrestrial? Well, maybe, but what about him having the human ancestors? He might be from another planet but having ancestors from earth has led science to consider two reasons for this: Appearance & Sex.
Thanks to ‘convergent evolution,’ which has shown that the unrelated species to end up having similar features. For example, the wings of bats, bird, and pterosaurs all have evolved from arms.
So the reason# 1 for Superman’s human descendent is obvious: he looks human.
However, it’s likely possible the two species to have basic features, two arms, legs, and one head, it’s not necessary that every feature would end-up the same.
In case, whether humans and Kryptonians are identical because of convergent evolution or both species share common ancestor, it’s more possible that Superman is a human descendant.
Jor-EI, Superman’s father, explained: “Long ago, in the era of growth, we raced through the stars in the search of a new world to settle upon… For over 100,000 years, our evolution thrived, achieving wonders.”
The movies didn’t offer any earlier information beyond 100,000 years ago, so we can fill the gap with whatever is known from evolution.
The search from paleontology, archeology, and genealogy has provided ample evidence on humans being originated from artefacts, fissile bones & DNA and the modern human has drifted out of Africa about 200,000 years ago.
Can human and Kryptonian have children together? Yes, at least according to Superman Returns 2006 in which Superman has a son with Lois and the comic Kingdom Come in which he is expecting a baby with Wonder Woman. But in other movies, Superman can’t have babies and DNA incompatibility is the reason.
Geographic isolation can have its effects on Reproduction isolation. Just like a tree branch becomes two including the production of geographic barriers that divide the population into two like a mountain range.
Clark and Lois have affection, so that’s not the case with Kryptonians and humans. Another prospect could be hybrid incompatibility that happens when genes mount up change over time. As a result, it will block sperms and egg from intermingling.
Of course, the common and known difference between Superman and normal human is the superpower. Superman is both alien and human; alien refers to the recent extraterrestrial origin and human describes evolutionary ancestry. He is actually a Superhuman and a Man Of Steel.