Are aliens humanoid and will there be humanoid aliens?

In many science fiction books, but especially in movies and series, the aliens are humanoid. On the other hand, there are science fiction works that describe humans in the distant future as different from us after undergoing evolutionary changes due to mutations

 The article was published on 1/11/2002 and is uploaded to the main page on the occasion of the transfer of knowledge Search for life in space and scientist Aliens and UFOs to the new site.

There are science fiction stories where aliens have the power to take human form, or make us see them as humanoid so that we don't notice them or fear them. But in many stories they "really" resemble us. Obviously, in the photographic media - cinema and television, it is easier to show the aliens as humanoid instead of building dolls or creating computer characters. Sometimes they look just like me and you and sometimes they are varied by one or more of the following characteristics - pointed ears, drawn eyebrows, mottled or rough skin, or an addition of one kind or another in the head area. Sometimes the story is that they are similar to us in everything, except that their internal organs are different, or the composition of their proteins (including the blood of course) is different.

So much for science fiction. But what is really happening? Are the aliens humanoid? Could they be in human form or at least resemble him?

Meetings of the third kind

There are many people in the world who can answer that in the affirmative. These are the same people who they say met aliens who visited their yard or their room at night, or they were abducted by aliens, flew a little in their spaceship or underwent various treatments by them. A typical description of those aliens as reported by those who have "encountered" them is a general human form, but usually shorter, hairless, white, gray or silver skin color, huge head with a wide forehead (triangle shape), huge eyes , the absence of a nose or a very small nose, a small mouth and no genitalia (if not clothed and visible).

It does make sense from a functional point of view (and therefore also from an evolutionary point of view) that intelligent aliens have sensory organs in the front of their bodies (head) and have organs of movement (legs) and manipulation organs (hands), but from here to the assumption that they look like us, the road is long. In our world, over a million species of living creatures are known (and there are perhaps another 30 million unknown species - most of them arthropods - insects and the like - and other invertebrates). Their form diversity is amazing and in the past the earth was inhabited by extinct creatures in the amount of more than a billion different species! Among them are those that are not at all similar to the creatures that exist today. How similar are we to an octopus or a dinosaur and how likely are we to be similar to creatures that evolved on another planet?

Similar although not close

We are closer to every creature on our planet - including plants - than we can be close to any alien, because the building blocks of the proteins of all creatures on Earth are the same (all creatures have a common ancestor). In contrast, the building blocks of life that evolved on another planet are quite different, for reasons of probability. A certain similarity is possible - for functional and environmental reasons. This is known as evolutionary convergence and it explains, for example, the morphological similarity between fish and certain marine mammals (whales and dolphins) as well as the ancient marine reptile Ichthyosaurus that looks quite similar to a fish. Likewise, the ability to fly in different classes of animals (insects, birds, bats and ... pterodactyls) is explained by evolutionary convergence, which suggests that aliens may have similar features to ours beyond formal similarity. In summary - there may be a similarity between us and the aliens at the level of something like a head and like limbs (at the level of our similarity to the other multicellular organisms, i.e. like a similarity between us to insects, see for example "men in space"), but not as the aliens are described in the reports of the people who "met" them and As the humanoid aliens are depicted in many movies and series.

time travel

And by the way, what do you think of all those cases where people report that they were visited by aliens or were abducted by them - actually these are not aliens, but visitors from the future? (This is on the weak assumption that it is not an imagination or a hallucination). Many science fiction works tell about visitors from the future, but ones that look just like us. The "visitors" that people are reporting on today and whose description we mentioned earlier, look a little different from us. So maybe the story is that they are the descendants of the human race from a period of tens or hundreds of thousands of years in the future and have undergone an evolutionary change. They visit us for reasons reserved to them. Those who want to find a reason can find plenty of examples in books and several movies from recent years.

All human beings are equal

Let's check if it is possible for man to undergo a fundamental evolutionary change so that he looks a little different - like in some science fiction movies from the XNUMXs, or like the "visitors"?
The ancestors of the natives in the Americas - the Indians of all kinds, the Mayans and the Aztecs - arrived there over ten thousand years ago and since then there was no contact with them until 500 years ago. The ancestors of the aborigines - the natives of Australia, arrived there about fifty thousand years ago and their connection with the islands to the north was extremely loose, if at all. The ancestors of the Tasmanians came from Australia to Tasmania about ten thousand years ago and since then there was no connection between them and the continent (until they were eliminated, by the white settlers, until the last of them).

Small and isolated populations are one of the causes of evolutionary changes. It turns out that tens of thousands of years of isolation are not enough to create evolutionary changes and today, after the voyages of discovery and because of the means of transportation, the whole world is one human population - there is no isolation and there are cases of mutual reproduction between populations that were previously isolated. For the sake of demonstration, we note that the time that passed between the existence of the ape species that was our common ancestor with the chimpanzee and the gorilla, is five to eight million years and the beginning of the appearance of modern man was no more than two hundred thousand years ago. But then the populations were isolated which allowed the creation of new species as a result of mutations; But today, this is not possible because all human populations and races are interconnected.

Human mutations

But there may be a post-catastrophe situation that affects the Earth, such as a massive meteor strike, or a nuclear holocaust that will result in the massive destruction of creatures on Earth, including humans. If a small population of humans remains, or a number of isolated populations, random mutations that will occur (and if it is a nuclear holocaust, mutations are to be expected as a result of the radiation), will be able to cause the formation of a new species of humans that will be slightly different in shape and characteristics from our species. Here is the place to emphasize that most mutations fail to create new species - the mutants fail to survive or reproduce and therefore the mutation becomes extinct. But in rare cases, the people with the mutated genes, their ability to survive or reproduce is not impaired, and perhaps the trait for which the altered gene is responsible, is useful in the newly created environment. In such a case, the mutant gene, or several of them, spread within several generations in the population, thus creating a new species.

It is quite possible that in tens of thousands of years a new species will be created from the human species whose change in external form will be at the same level of change as the aliens who "visit" us and whose description we mentioned earlier (but it is important to emphasize that it is not possible for them to be sexless or without genitals). However, the chance of this is not particularly great - the more likely possibility is that the human race on Earth will be completely destroyed and no new species will grow from it. That is why the programs that have been talked about recently are of great importance - space colonies, in space stations or on planets and moons in our solar system, or ships carrying colonies that will traverse the galaxy. Only in this way will the human race continue to exist in the event of a catastrophe on Earth. And in such cases, human populations that will be isolated for tens and hundreds of thousands of years in space and in other environments, will develop into varieties and even species different from us.