The Scientific Explanation For Humans' Belief That Space Aliens Look Like Octopuses

Because they just do...? JL

Science World reports:

The big eyes, outreaching and slithering tentacles and boneless body of the cephalopod make for good horror. They seem alien in the sense of very much unlike us, utterly different and without any empathy or common ground.
In the recently released film Arrival, Amy Adams plays a linguist responsible for figuring out how to communicate with aliens who have landed on Earth. Visually, the aliens, called heptapods, are a testament to masterful movie magic: Everything from their subtle, fluid movements to the dense atmosphere where they breathe fits with the idea of biological possibility. These otherworldly life forms seem truly feasible and may even be mistaken to be real. "Early on before they started filming, I read a few drafts of the screenplay, and I was asked to give feedback on some of the more linguistically relevant parts," said Professor Jessica Coon, who teaches linguistics at McGill University, recently told Business Insider.
"A lot of the comments they took into account. Some of them they said, 'Linguists in the end are not Hollywood's main audience, it'll be all right if some of these don't make it in' in the end, it turned out great, I think."
The movie is believed to have portrayed how people think aliens look like. However, what makes the heptapods in Arrival very believable is the fact that they are not all that alien to start with. From their body shape to their tentacles to their ability to squirt an ink of sorts, heptapods bear a strong resemblance to Earth's most alien intelligent life: cephalopods (squid and octopus).
"The big eyes, outreaching and slithering tentacles and boneless body of the cephalopod make for good horror," says Eddie Bullard, a historian specializing in UFOs and aliens. "They do indeed seem alien in the sense of very much unlike us, utterly different and without any empathy or common ground."
Humans have always been fascinated by the idea of alien life. Years before Jesus Christ was born, scholars had suggested that life might have had existed on other worlds, including the Moon. Given the alien nature of octopuses and their relatives, it may come as no surprise that they have inspired creative minds.
Meanwhile, the 19th century author Camille Flammarion described a planet full of perpetually swimming, tentacled seal-like beasts, for example. And of course, every sci-fi enthusiast remembers the slimy, brown invaders with their "Gorgon groups of tentacles" brought to life in H.G. Wells' War of the Worlds. However, aside from these few exceptions, before World War II, the imaginations of science fiction authors rarely took a side route from humanoid reality. Tales of the extraterrestrial generally consisted of green or gray men with large eyes from planets within our solar system, Quartz reported.
Then, in the 1940s, science fiction exploded with a variety of peculiar alien forms. However, Octopoid creatures have always remained fan favorites. From the cartoonish Zoidberg (Futurama) and Kang and Kodos (The Simpsons) to the aliens of Prometheus and Arrival, modern storytellers seem particularly fond of drawing upon the depth for inspiration.
It is also important to note that there have been a number of reasons why using squid and octopus as models for alien life makes sense. The oceans are like an alien world, with an atmosphere humans cannot breathe that gives birth to bizarre forms beyond people's imaginations. And cephalopods are about as far from the classic mammalian arrangement as one can get -- yet they display surprising intelligence.

Aside from the previously published report associating octopuses to aliens, there are still a number of reasons why humans are convinced that octopuses are the exact description of aliens. Octopuses use tools, they play, they can solve problems and puzzles and they may even engage in warfare with improvised weapons. They are the only invertebrate that displays a level of thinking scientists ascribe to consciousness. Indeed, any aquarist who has attempted to keep such creatures in captivity learns quickly just how smart these animals are and just how much work is required to keep them happy and healthy.