Octopuses have large optic lobes, areas of the brain dedicated to vision, so we know it is important to their lifestyles. 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. Every time the person passed the tank, the octopus squirted a jet of water at her. Over the course of two weeks, one person fed a group of octopuses regularly, while another person touched them with a bristly stick. At the end of the experiment, the octopuses behaved differently to the 'nice' keeper and the 'mean' one, which confirmed the octopuses could distinguish the two individuals, despite the fact they wore identical uniforms.
Octopuses keep surprising us - here are eight examples how
Many male octopuses lack external genitalia and instead use a modified arm, called a hectocotylus, to pass their sperm to the female. Jon says 'The appearance of the hectocotylus varies between species. Some look like a syringe, others more like a spoon and one - belonging to the North Atlantic octopus Bathypolypus arcticus - even looks like a little toast rack.
Once a male has handed over his sperm, it's game over. Most male octopuses die within a couple of months of mating. They keep up this behavior until the eggs hatch. In shallow-water species it can last up to about three months, but some octopuses take their level of care to the extreme. The title of 'mum of the year' goes to Graneledone boreopacifica. This deep-sea octopus was observed brooding her clutch of eggs for 53 months - that's nearly four and a half years. It's the longest brooding period known for any animal.
During the course of 18 dives to the depths of Monterey Canyon, California, the researchers never saw the female leave her eggs or eat anything, not even crabs or shrimp that wandered close by. Instead, the researchers saw the female fading away - she lost weight, her skin became loose and pale, and her eyes grew cloudy.
Why Not Eat Octopus? | The New Yorker
Her astounding self-sacrifice gave her offspring time to reach an advanced stage of development. On the researchers' final visit, the eggs had hatched and the female was gone. Although no other octopus is known to look after their eggs for such a long time, virtually all share the same fate: inevitable death. Since male octopuses don't survive for long after sex, the sea is full of little orphan octopuses. Jon explains, 'Thousands of specialised cells under their skin, called chromatophores, help them to change colour in an instant. In addition, they have papilli - tiny areas of skin that they can expand or retract to rapidly change the texture of their skin to match their surroundings.
Perhaps the most impressive of all self-concealers is the mimic octopus Thaumoctopus mimicus. Discovered in in Indonesia, this octopus doesn't copy surrounding rocks, reefs and seaweed like other octopuses, but instead disguises itself as other animals that predators tend to avoid. By contorting its body, arranging its arms and modifying its behaviour, it can seemingly turn into a wide variety of venomous animals. Lionfish, banded sole and sea snakes are among those it impersonates.
Jon says 'Plenty of other creatures pretend to be other animals, but the mimic octopus is the only one that we know about that can impersonate so many different species. It's a true shape-shifter. Mimic octopuses can flee from danger while disguised.
This octopus is imitating a venomous banded sole. It even copies the swimming style of the flatfish. Scientists even suspect that the mimic octopus selects a creature to impersonate based on what's living in the area, choosing one that represents the greatest threat to its potential predator. When a mimic octopus was attacked by territorial damselfishes, for example, it disguised itself as one of their predators, a banded sea snake.
In , researchers reported another cunning solution for moving away from danger without breaking the camouflage illusion: walking away on two legs well, arms. In the first example of bipedal locomotion under the sea, two tropical octopuses were found to lift up six of their arms and walk backwards on the other two. This allowed the algae octopus Abdopus aculeatus to keep its other arms extended and maintain its appearance of algae even while moving. Meanwhile, the veined octopus Amphioctopus marginatus walked with six of its arms curled under its body, possibly to appear like a coconut rolling along the seafloor.
Both were able to move faster than their usual many-armed crawl. But in , scientists made a surprising discovery in Jervis Bay, Australia: the supposedly solitary gloomy octopus Octopus tetricus actually builds underwater cities. Congregations of dens are formed from rock outcrops and discarded piles of shells from the clams and scallops the octopuses had feasted on.
Population sizes certainly aren't up to London standards, with only around 15 occupants living in Octopolis, as it was dubbed, and Octlantis - a second, nearby octopus commune studied in City living has its advantages and drawbacks, as we all know. Frequent aggression, chases and even den evictions were observed among the octopuses living at Octlantis.
The researchers say they're not sure what the benefits of living in a densely populated settlement are for these octopuses, but it may just be a case of necessity, with limited den spaces available in the otherwise flat and featureless area. Well, the blue blood is because the protein, haemocyanin, which carries oxygen around the octopus's body, contains copper rather than iron like we have in our own haemoglobin.
The copper-based protein is more efficient at transporting oxygen molecules in cold and low-oxygen conditions, so is ideal for life in the ocean. If the blood called haemolymph in invertebrates becomes deoxygenated - when the animal dies, for example - it loses its blue colour and turns clear instead. An octopus's three hearts have slightly different roles. One heart circulates blood around the body, while the other two pump it past the gills, to pick up oxygen.
Brimming with enthusiasm for the natural world, even Charles Darwin didn't always get it right. Curator Jon Ablett tells the tale of how an elusive monster from the deep came to be one of our popular attractions.
By Lisa Hendry. More than one brain It's a well-known fact that octopuses have eight arms. Jon Ablett, curator of the Museum's cephalopod collection including octopuses , tells us more:. An octopus floats against a backdrop of blue ocean off Hawaii. The mollusks are intelligent, playful and full of surprises, according to Sy Montgomery, author of the book. For most of us, the idea of having our hands stroked by a rubbery arm covered in suckers is not that appealing. Here is a baggy, boneless body that can pour itself into the tiniest spaces, has venom like a snake, ink like an old fashioned pen, a beak like a parrot, can taste with their skin, and can change color and shape.
These are amazing powers. That is a real honor. Read: Octopuses are Playful, Curious, and Smart.
Each of the octopuses you write about seem to have had individual personalities—tell us a little about Octavia and how she was different from Kali. Octavia was caught wild. She was older than Kali, probably more mature than any of the octopuses that lived at New England Aquarium. One of the things that she learned par excellence, was camouflage. That involves millions of muscles and nerves and decisions.
Talk about multi-tasking!
She was very wary and not eager to reach out to us and touch us at first. But, when she finally did, we became very, very good friends. It was a friendship that lasted… to the end of her life. Kali was maybe nine months-old, or younger. She was very playful, very funny, had a great sense of humor, loved to explore, loved to engage people!
She managed to seduce us all.
Data Protection Choices
Everyone loved her, instantly. Oh, my gosh, they are so smart! We have been outwitted many times, but one of the most dramatic outwittings was done by Octavia. There were three people petting her, and a couple of people standing around watching the interaction. Octavia had managed to steal the bucket right out from under us. And, what was she doing with it?
She wanted to play with the bucket. I think she enjoyed stealing it out from under our noses. You relate humorous stories about octopuses in labs. Tell us some. Can octopuses really run? Oh, boy, can they run! The students often try to get them out of the tanks to run mazes or for experiments and these little guys will use the net like a trampoline, jump off the net on to the floor and run around like a cat!
But, it totally was happening. Octopuses are also really smart about getting out of their tanks. Aquariums work really hard to make octopus-proof lids.
Copyright 2019 - All Right Reserved