They have bulbous heads, large eyes, and eight very useful arms. Octopuses are highly intelligent animals, masters of camouflage that have evolved an array of tricks over tens of millions of years to avoid or thwart would-be attackers.
They can match the colors and even textures of their surroundings, allowing them to hide in plain sight. If a predator gets too close octopuses can escape quickly, shooting themselves forward by expelling water from a muscular tube called a siphon. Their soft bodies mean octopuses can fit into impossibly small nooks and crannies, as long as the holes are not smaller than the only hard parts of their bodies: their beaks. If all else fails, octopuses can lose an arm to an attacker and regrow one later.
Octopuses can open clamshells, maneuver rocks—even dismantle the filtration systems of an aquarium tank. Another shot a jet of water at a light to cause a commotion. There are around species of octopus and they are found in every ocean. Most live on the seafloor , but some, like the paper nautilus , drift nearer to the surface.
Octopuses mostly feed on crabs, shrimp, and mollusks. Solitary animals, they typically live alone, sometimes in dens they build from rocks, sometimes in shells they pull over on top of themselves. Two deep-sea octopuses in the Graneledone genus — G. These warty protrusions, it turns out, can be used to distinguish the two species , which have been incredibly difficult to tell apart.
Scientists reporting June 7, in the journal Marine Biology Research catalogued the distribution of warts on both species, pinpointing two variables that were consistent across the individuals within a given species: distance between the warts and the tip of the mantle and the extent to which the skin bumps spread down the creature's arms.
Octopuses have an excellent sense of touch , according to the World Animal Foundation. Their suckers have receptors that enable an octopus to taste what it is touching.
Most octopuses — those in the suborder Incirrata or Incirrina — have no internal skeletons or protective shells. Their bodies are soft, enabling them to squeeze into small cracks and crevices, according to National Geographic. In April , an octopus at the National Aquarium of New Zealand squeezed out of its tank and made an eight-armed dash for a drainpipe that — luckily for him — led directly to the sea. A bulbous sack-like body, or mantle, is perched on top of an octopus' head.
The only hard part of their bodies is a sharp, parrot-like beak that is on the underside, where the arms converge. Octopuses have powerful jaws and venomous saliva, according to National Geographic. Octopuses weren't always squishy creatures. The ancestors of octopuses and squid sported hard shells. A study published online March 1, in the journal Proceedings of the Royal Society B: Biological Sciences revealed these marine animals lost their hard "mobile homes" in the Jurassic and Cretaceous periods.
This shell loss likely helped the ancient relatives of today's octopus, squid and cuttlefish become more agile to evade predators and nab prey, the researchers said. An octopus has three hearts. One pumps blood through its organs; the two others pump blood through its gills, according to the World Animal Foundation.
Octopus blood is blue because it has a copper-based protein called hemocyanin. When an octopus is swimming, the organ that delivers blood to the organs stops beating. This exhausts the octopus, which is likely the reason they prefer to crawl than swim, according to the Smithsonian article. Octopuses come in many different sizes.
Octopuses have about as many neurons as a dog - the common octopus Octopus vulgaris has around million. About two thirds are located in its arms. The rest are in the doughnut-shaped brain, which is wrapped around the oesophagus and located in the octopus's head.
Octopuses have demonstrated intelligence in a number of ways, says Jon. They're also adept at getting themselves in and out of containers. There is footage of similar sneaky behaviour and ingenious problem-solving happening in the wild.
For example, this BBC video shows a giant Pacific octopus Enteroctopus dofleini poaching crabs from a fisherman's pot:. Meanwhile, the sneaky larger Pacific striped octopus uses scare tactics when hunting for its dinner. It creeps up to its prey, such as a shrimp, and taps it on its shoulder. More often than not, the startled shrimp leaps away from the arm that touched it and darts into the clutches of the waiting octopus. It's handy having seven additional arms. Tools use is relatively rare in the animal kingdom and is something we tend to associate with apes, monkeys, dolphins and some birds particularly crows and parrots.
It is a good indicator of the ability to learn. Among invertebrates, only octopuses and a few insects are known to use tools. Jon elaborates, 'As well as solving tasks using tools to get food rewards in the lab, in the wild octopuses have been shown to build little dens, and to use stones to create sort of shields to protect the entrance.
Small individuals of the common blanket octopus Tremoctopus violaceus carry tentacles from the Portuguese man o' war as a weapon. These tentacles carry a potent and painful venom - the common blanket octopus is immune but can inflict their effects on unwitting predators and prey. The most impressive and convincing example of tool use by octopuses came in , when a few veined octopus Amphioctopus marginatus individuals were observed collecting discarded coconut shells in Indonesia.
After they dug up the shells, the octopuses gave them a good clean with jets of water. They then carried them to a new location and assembled them as a shelter. Travelling with the shells underneath their body resulted in a slow and ungainly 'stilt walk' along the sea floor. This makes the octopuses more vulnerable to predators, but it seems they are willing to accept the short-term risk for future protection. The scientists who discovered the behaviour argue that this, and the fact the shells are carried around to be used when needed, is conclusive evidence of genuine tool use.
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. Scientific American reported a story from the University of Otago in New Zealand where a captive octopus apparently took a dislike to one of the staff.
Every time the person passed the tank, the octopus squirted a jet of water at her. Biologists at the Seattle Aquarium designed an experiment to test the recognition abilities of the giant Pacific octopus. 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. 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. The only other octopus species known to move this way is the Algae Octopus, although recent evidence has shown this behavioral repertoire is also found in the Common Octopus.
Adult Coconut Octopuses usually weigh between to grams and are just 6 inches 15 cm wide, including the arms which usually make up half of that length. The Coconut Octopus is a carnivore and eats mostly shrimp and crustaceans which they gather from the mud holes, it will also eat small fish if it can catch them. The hunting technique of Coconut Octopuses can be described as foraging, it uses an active predatory style as well as a passive approach to catch prey.
This is displayed in the way that they appear to wander about the sea floor whilst they are in hunting mode, until it encounters suitable prey.
Caribbean Reef octopuses are a warm water species and are common throughout the waters South Florida, the Caribbean, and Northern South America. They are rarely seen during the day but are frequently seen at night in shallow saltwater reefs.
These octopuses are usually rather bulky in appearance but are in fact relatively small, with an overall size measuring up to 60 cm across, its mantle making up around 2 to 4. In order to escape, The Caribbean Reef Octopus will eject a cloud of foul tasting ink towards its attacking predator. Whilst in a passive hunting mode they will usually be in their den, burrowed in the sand or a coral crevice with only its eyes sticking out.
Flapjack Octopuses get their name from the intriguing way they deflate themselves to appear more flat, thereby giving the illusion that they are non threatening to would be prey.
The habitat for this species is on the seafloor, approximately to feet to 1, m deep, because of this great depth, they are very rarely spotted. The Flapjack Octopus belongs to the group of Umbrella Species, a type of pelagic octopus characterized by a web of skin between their tentacles.
Adding to the cuteness of this charming species are their distinctive fluffy orange body and short tentacles.
During the day and night they hunt for their prey which consist mostly of crustaceans, small worms and other invertebrates. They hunt for prey using surprise, suddenly pouncing on them and using their hardened beaks to kill, before devouring them. Discovered in , the beautifully strange and elusive Blanket Octopus can be found in both subtropical and tropical oceans.
Unusually, female Blanket Octopuses are much bigger than males, up to 10, times bigger and can reach up to 6. These elegant blanket like sheets are not to look pretty, instead females use this web to warn off potential predators. Spreading her ams out to greatly increasing her apparent size, the web forms a silhouette which makes her appear much more intimidating. However, if this deceptive trick does not succeed, they can detach these fleshy sheets, causing the predator to be entangled in her web, giving her time to escape.
But unlike other species, the males employ one of the most bizarre methods of hunting prey — ripping a stinger from the Portuguese Man o' war , to use as a weapon. As its name suggest, the Common Octopus is widely distributed in tropical, subtropical, and temperate seas throughout the world. It is a well-known medium sized species of octopus, that lives between the surface and a depth of feet m.
This species was also the star in the award winning documentary — My Octopus Teacher. They are found frequently relaxing in holes along the sand-bed or crevices in the reef, and can squeeze through any hole that's larger than its beak. Recent observations have shown that the Common Octopus also has the ability to travel whilst walking on just two arms.
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