Are Aliens Enormous? One Scientist Believes They’re More Like Polar Bears Than ET

Do you have a picture in your head of what an alien should look like? If so, it’s probably of a vaguely humanoid little green man. And your imagination would be wrong. One scientist believes aliens would actually be enormous.

Enormous as in the size of a polar bear – or about 650 pounds. How did science come up with that comparison? You have Cosmologist Fergus Simpson of the University of Barcelona to thank for the enormous alien theory – which, of course, is all for fun.

The cosmologist broke down his theory in a paper at arxiv.org, Newsweek reported.

“Throughout the animal kingdom, species which are physically larger invariably possess a lower population density, possibly due to their enhanced energy demands. As a result, we should expect humans to be physically smaller than most other advanced species.”

So basically, Simpson’s enormous alien theory goes something like this: It’s based on the assumption that aliens – should they exist – conserve energy about the same way us earthlings do. That theory states that small animals outnumber large ones simply because they use less energy.

Throughout space, Simpson speculates that – again, like on Earth – smaller animals outnumber the bigger ones. Planets inhabited by smaller animals may also be more numerous than planets inhabited by bigger animals; in all probability, then, Earth is home to space’s littlest creatures.

Aliens are probably enormous because that means (like polar bears) they would live longer, and the longer they live, the better chance aliens have of figuring out how to contact us (like these radio bursts, perhaps).

However, there are some holes in this sci-fi theory, which turns the diminutive ET of our alien fantasies into a enormous, polar bear-sized – and much more frightening – green man. The cosmologist isn’t wrong in using Earth as way to understand other planets, but that method doesn’t take into account the fact that other planets have different gravitational pulls. And gravity effects the size of a planet’s theoretical creatures- including any aliens.

And, of course, Simpson has no actual data to back up his contention that aliens are enormous. More to the point, here on Earth, humans are quite the smarty pants and yet we’re not very big at all, argued fellow researcher Seth Shostak. Other factors helped to make us smart.

“Polar bears are large but do not write great literature and build radio towers. And a lot of that is probably because they are walking around on all fours.”

Though Simpson’s enormous alien theory is really just the stuff of imagination for now, he wrote in his paper that the idea that aliens may be quite a bit different than we expect should make us comb the cosmos for alien life with a sharper eye, he told Popular Mechanics.

“As we have repeatedly learned from the discoveries of distant planets, and the exploration of life on our own, nature is invariably more diverse than we anticipate, not less.”

[Photo Courtesy Evening Standard/Getty Images]