Have you ever watched a Scifi-Movie with aliens in it, which looked very human and wondered why that would be?
Then you had the same train of thoughts I had many times. And after I watched a
“Sciency” video where they talked about convergent evolution, I checked that out and had an idea.
And now, to explain why I think humanoid aliens are realistic, I have to talk about two different things first.
Firsts or all: When a species changes its genetic code over millions of years, to adapt to a new environment that is called evolution. That often results in a species having multiple “offspring” species.
For example: specie A lives in a forest, that slowly disappears. Now specie A has to go to new places, with different conditions. It splits into two groups. Half B of the specie A and half C. Half B moves in a desert and evolves some kind of heat releaser. Half C on the other hand moves into a swamp and evolves floating skins or so. Now we have two species from the same ancestor-specie, which have mostly the same characteristics.
Now keep the scenario of my quick reminder on evolution in mind. So, what if, specie
D too had to move into the swamp specie C was living in and evolves the same kind of floating skins?
That’s what we call Convergent Evolution.
More precise: convergent evolution is, when two not closer related species evolve the same thing. For example floating skins, like in the scenario above.
After we’ve talked about the first half of my theory, we need to talk about the Fermi-Paradox, or actually about that what the paradox is saying.
There are millions of stars like our own in the milkyway and many of them probably have planets in their orbit, on which life could exist. Including the fact, that the universe is way older that the earth, there should be some signs of alien civilisation, some where in the universe, but nothing. Humanity never got a clear sign or signals of extraterrestrial life.
So we could assume, life is pretty rare and the only example we have for it, is on our home planet. Given that, shouldn’t a planet that is exactly like the earth, be the perfect spot for life to come into existence? One could think so.
Now to my theory: when life everywhere in the universe is most likely to evolve on a planet like earth, shouldn’t take evolution at least a similar path like it did here?
Wouldn’t that mean that the best thing evolution could come up with, is at least similar on every earth-like planet?
I talk about things like, walking on two limbs, similar proportions, hands, feet and eyes. Things that probably caused humans to rise and now be the only specie on planet earth which can shoot cars into space.
Thanks for reading!
Here are a couple of sources and videos through which I came up with my theory:
Convergent evolution explained:
https://www.sciencedaily.com/terms/convergent_evolution.htm
A video from Kurzgesagt, explaining the Fermi paradox (short):
Isaac Arthur talking about the Fermi paradox and great filters (very long):
