Aliens in cinema have a tendency towards being human-like. In Star Trek, for instance, the aliens have a tendency to be humanoids that homogenously reflect an aspect of humanity. Vulcans are our rationality, Ferengi are our greed, Klingons are our aggression. The depiction as humanoid is entirely understandable, of course. Non-humanoid aliens would be crazy expensive to depict, and doing it too often would burn through special effects budgets fast. Making their culture and personality so homogenous, though? That's a little less forgivable. They tend to be, frankly, much less alien than many creatures here on Earth. In fact, we can draw a lot of important implications for alien life from some of the stranger life-forms here on Earth.
Worf, a Klingon from Star Trek, and, for all my complaints about the human-like aliens from Star Trek, one of my favorite characters in anything. Fair use image. [Image source]
There is some small defense for Star Trek aliens being so human-like. Many of the more interesting ways of organizing a brain and thinking seem to be resultant of your body plan. Octopi are a great example of this. They're the intelligent animals farthest away from us on the evolutionary tree- they're more closely related to clams than to us, and we're more closely related to cockroaches than we are to them. Many of their evolutionary traits are the result of convergent evolution, not a shared ancestor- our ancestry split well before the first eyes evolved, for instance. They evolved eyes completely separately from us, and they're very, very different than ours. We did evolve nervous systems before our last common ancestors, so those are more similar than not, but there are still some major, major differences.
First off, octopi brains are donut shaped. They wrap around their esophagus, then radiate nerves outwards into their tentacles. Because of this, octopi (and other cephalopods) have to be very, very careful about what they eat. If they eat anything to big and pointy, it could actually stab into their brains. Their brains are also huge in size- the largest of any invertebrate (thought cuttlefish are tied.) This is where their nervous systems get really interesting, however- only a third of an octopus' neurons are located in its brain. The rest are located in its arms. The arms are actually capable of acting and reacting on its own. The arms have the ability to process their own sensory signals and act accordingly- they have both touch receptors and cheporeceptors on their arms- they taste everything they touch. The arms are, in effect, semi-autonomous. When chopped off and then given food, they'll try and deliver the food to the mouth.
The common octopus. [Image source]
This helped answer one of the major questions scientists had about them for a while- how do cephalopods control their eight arms? It takes a lot of brain-power to control a limb, especially a dextrous one, and even more especially operating limbs doing different activities from one another. It's easy for a millipede to make all its legs walk forward, but have you tried doing different activities with each hand? It's definitely tricky. And yet, octopi regularly do different activities with each of their arms. It turns out that octopi aren't actually controlling their arms- their arms are doing their own things. The octopi can tell them all to start walking in a direction, and the arms cooperate without much conscious input from the octopi. The octopi can, however, take control of one or two limbs directly for delicate or complex tasks if it chooses.
So what implications does this have for alien life? Well, for starters, there's no reason we can't have aliens with crazy tentacles. They don't need to expend a disproportionate amount of their brain's processing power on operating them, let the tentacles handle themselves. Even more interestingly, you could have the tentacles give actual feedback and store memories- one tentacle, for instance, might influence the alien to be more aggressive, while one might be more curious. The loss of the latter might cause the alien to become much more warlike and intolerant. It could get even more complex than that, and each tentacle could have its own personality.
Photogenic little fella. [Image source]
Next up: Cnidarians, Ctenophores, and more!
- Other Minds: The Octopus, The Sea, and the Deep Origins of Consciousness, by Peter Godfrey-Smith
- Squid Empire: The Rise and Fall of the Cephalopods, by Danna Staaf
- Are We Smart Enough to Know How Smart Animals Are?, by Frans De Waal