During quiet sleep, octopuses are motionless; their skin is pale and their eyes are narrowed to tightly shut slits.
Octopuses are thought to undergo two different stages of sleep: “quiet sleep” and “active sleep”, the latter of which involves twitching body parts and rapid changes in the texture and patterning of the skin.
This wild sleep is rhythmic, happening every half an hour or so, and brief; it's over after about 40 seconds. Active sleep is also rare; the octopuses spent less than 1 percent of their days in active sleep, the researchers found. Active sleep in octopuses is somewhat like REM sleep in people, Medeiros says.
Jon adds, 'Octopuses appear to be able to recognise individuals outside of their own species, including human faces. It's not unique behaviour - some mammals and crows can do it too - but it is rather unusual.'
Octopuses usually change their skin color for camouflage or for communication but during sleep, environmental factors no longer trigger these patterns. The researchers inferred that the color changes during sleep results from independent brain activity.
An octopus is pale whiteish-gray all over during quiet sleep with eyes tightly shut and hardly moving.
The areas around the eyes, suckers, arms, and web may darken so the octopus appears more threatening. Their coloration also reflects their mood. While their pigmentation is normally brown, octopuses may turn white, which shows fear, or red, which demonstrates anger.
Octopus caretakers often emphasize that many octopuses voluntarily solicit touch, play, and companionship, even when there is no food or material reward involved. Presumably, if they did not want such interactions, they would not pursue them.
Octopuses can remember humans, says Josh Rothman at the Boston Globe, and "have particular human friends and nemeses." The animals recognize their own names when called out, crawling affectionately towards caretakers they like. If an octopus isn't enamored of you, he'll squirt water at you when you call.
It varies according to species, but octopuses, both wild and captive, live roughly 1 to 5 years. This short lifespan is a consequence of a reproductive strategy known as semelparity, meaning that octopuses breed only once in their lifetime and die shortly thereafter.
There is a consensus in the field of animal sentience that octopuses are conscious beings — that they can feel pain and actively try to avoid it.
It might seem abnormal, but most species of octopus can survive out of water for 30-60 minutes, allowing them to slink from pool to pool in search of food when the tide goes out. We rarely see these 'air raids' because cephalopods typically hunt at night!
Octopuses can survive outside the water for about 20-30 minutes, and some aren't making it back into the water in time.
Octopuses in a more stimulating environment, with larger tanks, crushed coral, plants and a view to a live fish in a nearby tank appeared healthier and happier. So your average fish tank setup probably isn't going to cut it for an octopus. Many species of octopus are also nocturnal.
Invertebrates such as octopuses may experience other emotions such as curiosity in exploration, affection for individuals, or excitement in anticipation of a future reward."
Her camera captured the curious cephalopod drawing closer and closer, its tentacles widening until it fully embraced her. “It was just crawling on my camera, crawling on my lips, giving me a hug. These huge tentacles were up over my face and mask,” Humphreys said.
In both laboratory and ocean settings, the octopus is known to recognize faces. Vision is well developed in this species as various visual discriminations are readily learned, and in this the abilities of the octopus are comparable with those of vertebrates (Nixon 2003).
Pull away quickly.
In many cases, a human can escape from the grasp of a small-to-medium sized octopus by just swimming away.
The best way to keep an octopus is actually the method we originally recommended: a tank of adequate size or better, lots of live rock in the tank (a pound per gallon), a one-inch sand bed, a wet-dry filter and sump, protein skimmer, powerhead for extra circulation, and a simple fluorescent light.
Most octopus bites aren't fatal to humans, although they can cause swelling and pain. After interviewing over a dozen aquarists at aquariums all over the world, OctoNation's founder Warren Carlyle said “An octopus bite is extremely rare!
The Octopus vulgaris – the most common octopus species – will approach just about anything they think is fun, interesting or different, and the 'octopus teacher' becomes so accustomed to the diver being there that she basically treats him as part of the environment.
Octopuses' ability to recognize humans enlarges our knowledge of the perceptual ability of this nonhuman animal, which depends heavily on learning in response to visual information. Any training paradigm should take such individual recognition into consideration as it could significantly alter the octopuses' responses.
The 🐙 emoji is an octopus, and can refer to sea life in general. This is a pretty straightforward usage of the 🐙 emoji. It's an octopus, and it can be used to represent an octopus. In more general uses, it may also represent anything related to sea life (like the aquarium, or ocean).
A particularly intriguing behavior is throwing. Octopuses sometimes gather material in their arms, and then either carry and release it, or sometimes throw it out in a concerted, occasionally spectacular, way. The arms are used to first collect some combination of shells, seaweed, and silt.
When scared, octopuses will shoot a dark liquid, sometimes called ink, at the thing that scared them. This will temporarily blind and confuse a potential attacker, giving the octopus time to swim away.