The eye is an example of what philosopher Daniel Dennett calls an evolutionary “forced move.” The form of the eye is not predetermined. Eyes range from compound eyes to the virtual Schmidt cameras found in some deep-sea fish. But courtesy of geometrical optics and the survival advantages of gathering progressively better information about the world, evolution invents eyes again and again.
So, starting with a primitive nervous system, does each small step toward intelligence convey survival advantage? Does this mean evolution of intelligence is also a forced move?
If you have never Googled “octopus video,” you should. Octopuses are curious creatures, by which I mean they possess curiosity. They solve complex problems, have excellent memories and individual personalities, and learn by watching others. They play. They plan. They use tools. They are escape artists and annoy aquarium keepers by taking things apart to see how they work.
Humans and octopuses parted evolutionary company something like 700 million years ago, yet each evolved problem-solving intelligence. The Larger Pacific Striped Octopus has even evolved the beginnings of social intelligence. It mates beak to beak, lives in groups, shares dens, and lays eggs multiple times instead of only once. Given another few million years to evolve, it is hard to say where they might end up!
Citing the Cambridge Declaration on Consciousness, some researchers even suggest that octopuses may be sentient. They may think, feel, and experience. But what would consciousness be like to an animal with two-thirds of its neurons distributed throughout its body and arms that can act independently from the central brain? Cut off an octopus’ arm and the arm keeps
doing things, including capturing prey and trying to feed a mouth that is no longer there.
Many times while scuba diving I have settled in to watch an octopus with absolutely no doubt that the octopus was watching me right back. Is it a fluke that, starting from scratch, evolution invented intelligence more than once? Or does each small step toward intelligence offer some advantage, making intelligence, like the eye, an evolutionary forced move? If so, intelligence may be common wherever complex life appears in the universe.
But as I think about the octopus, I doubt that we can even begin to imagine just how profoundly “other” that intelligence might turn out to be.
Jeff Hester is a keynote speaker, coach, and astrophysicist. Follow his thoughts at
jeff-hester.com