Movies, TV shows, and video games have helped humanity paint a mental picture of what aliens might look like if we ever run into them, but most of the time those fictional depictions have little or no scientific backing whatsoever. Researchers searching for extraterrestrial life don’t necessarily know exactly what they’re looking for, but based on what we’ve learned about humanity’s rise there’s a handful of things nature tells us are required for advancement of a civilization. In the book “The Future of Humanity,” author Michio Kaku attempts to answer the incredibly difficult question of what aliens might look like, and this time it’s not just a guess.
Kaku consulted with exobiology experts and theorists who specialize in hypothetical alien life forms which have developed on far-off worlds much different from Earth. Using that accumulated knowledge, Kaku came up with a very basic list of criteria that any intelligence alien race would need to have in order to reach a level similar to humanity.
As the New York Post reports, the requirements that Kaku has dreamt up are essentially the same capabilities that scientists believe have allowed humans to progress in the way that we have:
- Stereo vision – Two eyes capable of focusing on a single object are something we typically associate with predators here on Earth. Prey animals often have one eye on either side of their head which allows them to spot threats and escape quickly, but that type of ocular setup is poor when it comes to hunting. Kaku suggests that most if not all “intelligent” alien races would have originated as hunters, rather than the hunted.
- Thumbs – Scientists have long believed that evolution which led to opposable thumbs was a huge factor in the rise of primates. A method of grasping objects allows for the making of tools which, it is thought, is one of the very earliest signs of intelligence as we know it. It makes sense that aliens would have followed a similar path.
- Language – This one is a bit tricky because it’s incredibly non-specific. The key here isn’t just the ability to communicate with each other in the moment — many animals have species-wide methods of vocal communication that could be considered language — but also to relay information and pass it down between generations. This allows the accumulation of knowledge over long periods of time and gives new members of a species the chance to expand and “stand on the shoulders” of those who came before them.
These features obviously sound a lot like what we’re all born with, which makes perfect sense. However, within this very basic outline there’s plenty of room for variation. If aliens only need two eyes, a gripping appendage, and some kind of language in order to have caught up with humans, there’s really no telling what form their bodies have actually taken, especially on planets with chemical makeup far different from Earth.