I’m a sucker for stories about octopuses. (See what I did there?) They are extraordinarily intelligent, have distinct personalities, and are capable of using tools, opening jars (from the inside or outside), or even recognizing faces and holding grudges. (See video below for more.)
The more we learn, the more scientific interest in these cephalopods grows, and for a good reason—they are genetically the closest things to aliens on earth.
There was a time when the octopus, or their relatives, were mainly the fascination of the movie theater; they were the monster’s of the ocean, as in Jules Verne’s 20,000 Leagues Under the Sea. (Side note: while it is implied that the monster is an octopus, it seems Verne actually had a squid in mind.)
Today, however, scientists have discovered a very different creature. Well, yes, they can still be terrifying—even cannibalistic—but they are more complex than that image.
They have, for example, nine brains—one central brain and one for each arm—and three hearts to our one—they also have blue blood. And the octopus is far more ancient than human beings, coming on the scene around 296 million years ago, to homo’s paltry 3 million year history.
Octopuses are also capable of editing their RNA without altering their basic DNA sequence—a helpful ability for survival. This suggests, according to a study published in Cell last year, a strong effect on the creature’s evolutionary history.
“Abundant editing requires abundant structures that can span a large fraction of the genomic coding sequence. Thus, although extensive recoding presents the species with a route toward proteome complexity, it comes with its own price tag. The constraints required to preserve thousands of recoding sites reduce the accumulation of mutations at positions in the proximity of an editing site, slowing down the rate of conventional, DNA-level evolution.”
It is this evolutionary background of the octopus that alludes to another likelihood: they are the closest thing we have to alien life on earth.
When we compare the intelligence of other animals, like certain mammals, we frequently appeal to our shared evolutionary heritage. It doesn’t surprise us when a bonobo is so much like a human because we share 99 percent of the same genes.
But here is where the octopus is different.
Unlike bonobos and chimps, where our common ancestor diverged around 6-8 million years ago, the common ancestor of humans and octopuses existed about 750 million years ago. That common ancestor was long before first primitive worm brains formed around 500 million years ago.
This means that the highly intelligent octopus, capable of doing things once thought limited to humans, but then thought limited to mammals and certain birds, found its intelligence by an entirely different evolutionary path. That history shows that there is more than one way to skin a cat—evolutionarily speaking, of course. Our evolutionary story is not the only way to intelligent life, meaning that intelligent life may not have to look anything like us.
In other words, according to Peter Godfrey-Smith, a CUNY philosopher studying animal minds, if you want to understand how alien intelligence could form, then “octopuses are the closest thing we have.”
There is tremendous diversity in life on earth, and that life continues to surprise us. (The Tardigrade, for example, is nearly impossible to kill and has been voted most-likely for surviving off-world missions on hostile planets.) But it is important to remember that this diversity can take many roads.
So while the alien of the week in Star Trek might usually look like us—and we associate that look with intelligence—it is likely that the first alien race we encounter will look nothing like us—and hey, maybe it will even try to eat our ship.