Cephalopods

"Octopus are thought to be very intelligent," says husbandry director Pam Lyons. "In captivity, we like to provide them with challenges and puzzles."

In addition to opening Easter eggs, the octopus at the Newport Aquarium travels through tubes for food. She can use her suction cups to taste the chemicals on people’s skin and responds most favorably to her keeper. Sometimes she sprays water at strangers.

"(Octopus are) really neat animals to work with," Lyons said. "They really have evolved to be very intelligent."

-- Excerpt taken from a 4 Your Info article

I've no doubt I've written before, but octopi fascinate me, along with their cephalopod relatives, squid and cuttlefish. They've been found to be among the most intelligent creatures in the oceans, with highly evoled eyes comparable in structure to our own. They've also been shown to exhibit advanced problem solving abilities, observational learning skills and the ability to use tools, as well as displaying camoflage, emotions and communicational abilities by means of their skin chinging it's texture and colour. Remarkable animals, really. What fascinates me is that they're one intelligent species on this planet that evolved entirely differently to us. Being as I was reading about all of this earlier this evening for entertainment value, I thought I'd write something on the whole subject...

Consider dolphins, for instance. Dolphins also exhibit many of the traits associated with advanced intelligence. Learning, communication, organisational abilities. The main difference is that dolphins are communal animals. However, in the evolutionary stakes, dolphins are relatively close to us. They're also mammals.

Octopi aren't even vertebrates. While our ancestors followed the vertebrates from being fish, out of the water up to where we are now, octopi are descended from molluscs. Snails and arthropods with scarcely anything in their biology that could be called a brain. In fact, octopi are molluscs. Perhaps that's what's so delightfully mysterious about them, considering the vast majority of molluscs are among the most primitive forms of macroscopic animal life.

"The brain is anatomically complex," says neuroscientist Ted Bullock of the University of California in San Diego. "It is very highly differentiated. It has a lot of texture, it isn't smooth or monotonous. It looks like a complicated brain, histologically and microscopically." Make no mistake, cephalopod brains cannot compare with the complexity of the brains of mammals or even birds. In brain size to body mass ratios, however, they outrank those of lower vertebrates, like reptiles and most fish.¹

However, to play devil's advocate (as I so often love to do), other studies have shown that the humble octopus has a very different nervous system to ours. It's been shown that octopi have bundles of nerves located in their tentacles as well as nerve cords (containing giant axions) located in the rest of their mantle (body).

The brain inside the octopus 'skull' sees a tasty sea morsel and decides to eat it, but to get the morsel into its mouth the brain inside the skull sends a message to a mass of nerves inside the octopus arm. That mass of nerves controls the arm movement to snatch the tasty treat.

"In this hierarchical organization, the brain only has to send a command to the arm to do the action—the entire recipe of how to do it is embedded in the arm itself," said Binyamin Hochner of the Institute of Life Sciences at Hebrew University in Jerusalem, Israel, and co-author of the research.²

Taking this into account, while still in the self proclaimed role of devil's advocate, maybe what we classically refer to as a brain may not be as complex as that of a mammal, but if we consider that there is nerve tissue performing brain functions throughout the octopus, it could be that it's extended brain is every bit as complex as that of the highest mammalian species -- us included.

Of course, this piece of conjecture is entirely the subject of speculation on my part, but you must agree, it's an interesting idea.

A long term fascination of mine is which species on Earth might be next to develop an intelligence comparable to our own. Personally, I'd love for marine biologists to prove the octopus to be that species. The whole idea of it seems... refreshing. That and it might curb the (IMHO) somewhat arrogant opinion of some scientists that intelligent life on other planets must somehow manage to be humanoid. Why not a species closer in physiology to a cephalopod?

I could ramble for a long time, but I shaln't. Suffice to say that studies have proven to just within a shadow of a doubt that octopi are intelligent, possibly sentient animals. Should future behavioural experiments prove to be conclusive, who knows? It could prove as much of a revelation to some biological disciplines as quantum mechanics was to chemistry and physics!

References:

1. What is this octopus thinking?
2. Octopus arms found to have \"minds\" of their own

Some links:

• Some octopus information
• The Octopus Research Group
• \"Ask the Aquarium\"
• Someone else who evidently likes octopi