Among the most intelligent animals on Earth, octopuses are unique because they are quite strange in their evolutionary journey to develop this intelligence. The philosopher Peter Godfrey-Smith has called the octopus the closest thing to an alien we might encounter on Earth, and their bizarre anatomy speaks volumes: an octopus’ spirit isn’t focused in its head but spreads throughout its body. Their tentacles are filled with neurons that endow everyone with a hyperconscious sense of touch, as well as the ability to smell and taste. Marine biologists have noticed that sometimes each tentacle seems to have its own mind. Each octopus is a tactile thinker, constantly manipulating its surroundings with a body so soft it almost feels liquid.
All of these things are surprising, at least in theory, as scientists have learned to associate intelligence with vertebrates and a tendency to socialize. Octopuses are either asocial or partially social, and all are invertebrates. This raises an obvious question: how did octopuses get so smart?
Scientists know surprisingly little about this subject, as much of the octopus neuroanatomy research so far has focused on one species, the European common octopus (Common octopus) – which has about as many neurons in its body as a dog. Thanks to the scientists behind a new study in the scientific journal Current Biology, we now know more about the neural wiring of four very different types of octopus (or, in one case, octopus-like animals): the vampire squid (Vampyroteuthis infernalis), which lives in the deep sea and is technically neither an octopus nor a squid; the blue striped octopus (Hapalochlaena fasciata), a poisonous creature that guards itself while roaming the ocean at night; and “two diurnal inhabitants of the reefs”, Abdopus capricornicus and Cyan octopus (also known as octopus of the day).
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Scientists also examined data on four other coastal octopus species based on previously published papers. Using this information and their new research, they concluded that the intelligence of the octopus had evolved in a similar fashion to that of vertebrate animals, especially based on the need to adapt to their environment. This implies that they had an evolutionary path converging towards the development of intelligence although they diverged from vertebrates a long time ago.
“Our study revealed new information to confirm that the octopus brain structure indeed evolved like that of many other animals,” said Dr Wen-Sung Chung, senior contact on the article and postdoctoral researcher at Queensland Brain. Institute in Australia. by email.
Chung compared the evolution of the octopus to the evolution of sharks, noting that sharks evolved differently depending on the ocean depths they preferred to swim at. ” It probably is [unsurprising] because they have a short lifespan and live in a wide range of oceans (from reef to deep sea, tropical to temperate waters) ”, all of which have different conditions in terms of predators to escape and others. pressures on survival.
“Octopuses and other cephalopods are most likely more complicated than we previously expected,” Chung added. “Expanding studies on various species from different habitats, rather than just one / a few iconic species, can be a way to study this amazing and seemingly intelligent creature. I think we can learn more by embracing the diversity of these creatures. “
Among other things, scientists didn’t expect to find as much aliasing as they did in octopus brains. The process by which the brain develops what appear to be wrinkles is known as gyrification and is associated with vertebrates whose highly evolved brains are able to process large amounts of complex information. Yet wrinkles have already been seen in brain sections for around 20 species of octopus, and the new studies have revealed compelling new evidence of structural brain folding in the octopod’s central nervous system.
“The folding of the brain is certainly a big surprise to us,” Chung wrote to Salon. “In order to confirm this, we had to catch individuals of different sizes (no way to get them from the pet store or the pet store) to eliminate the possibility of structural deformation caused by handling during capture, fixation and imagery. “
The study also provided new information about the vampire squid, a species that is neither octopus nor squid but rather the last surviving member of its own order. By examining his brain, scientists were able to learn that he possessed a strange hybrid with characteristics similar to those of a squid and an octopus. They also found that for octopus species that live in reef systems, their entire visual system undergoes major changes to adapt to their daytime lifestyle.
Does this mean octopuses are as intellectually complex as humans? Not so fast, Chung warned, noting that scientists can only say for sure that octopuses are smart enough to remember landmarks and come out of their tanks. (“It’s a nightmare for most octopus researchers,” he noted.)
“Honestly, this study is only the very first step to studying the differences / similarities between octopus / cephalopods, and we know too little about octopus in many ways,” Chung added. “We need to be careful about this and avoid over-interpretation at this point until more solid evidence is available in the future.”