9 Ways You're Picturing Aliens Wrong

9. Aliens Are Already Here

There is a vast array of biodiversity on planet Earth and, right now, only a tiny proportion of it is human-shaped.

Granted, a lot of it follows a few-limbs-and-a-face pattern and the various branches of the evolutionary tree can eventually be traced back to one common ancestor, but perhaps the closest analogue for an intelligent (even near human) alien being is the octopus.

Our eight-limbed friends have evolved in a totally alien environment to humans and, what's more, appear to have evolved intelligence completely separately, as our evolutionary paths diverged some 800 million years ago.

Cephalopods, particularly Coleoidea, are widely considered to be the pinnacle of invertebrate intelligence (their vertebrate equivalents being humans) and yet their nervous systems are fundamentally different to ours in most important ways.

Not only does this give us an important clue in our understanding of intelligence, but it's definitely a good omen for alien life that intelligence has emerged twice, completely independently, even if it was on the same planet.