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. Take a look at the unusual locomotion in this SciFri video featuring researcher Dr Christine Huffard:.
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 But they are far higher than scientists anticipated based on the loner reputation of O. 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. Discover where the real world and the Wizarding World intertwine, and how the wonders of the natural world have inspired myths, legends and magical creatures for generations.
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. Coral reefs attract deadly predators. Find out how their inhabitants survive using everything from camouflage to chemical warfare. Get email updates about our news, science, exhibitions, events, products, services and fundraising activities. You must be over the age of You have hemoglobin which contains iron instead of copper.
Because hemoglobin is an oxide of iron, it makes our blood red. Hemocyanin is a more efficient way for octopuses to transport oxygen in extremely low temperatures. This is why octopuses have hemocyanin instead of hemoglobin. Octopuses are not the only creatures with three hearts. Their closest relatives, squids, and cuttlefish also have three hearts. There are other animals that have even more hearts! The hagfish tops the list with four hearts and between five to fifteen pairs of gills.
The earthworm is sometimes listed as a multi-heart animal even though, the aortic arches of the earthworm are not technically hearts. Contrary to popular opinion, Octopuses only have one large brain. The bundles of neurons are highly specialized, however, and independently control the movement of each arm, taste, and feel objects freeing up the main brain to focus on other activities. Octopuses have only one stomach. Despite their having multiple everything — or almost everything, these intelligent cephalopods do not seem to want an extra stomach.
An octopus does not have any tentacle. It only has eight arms. People who are similarly confused by the squid also claim it has ten tentacles. A squid has eight arms and two tentacles. There are two main ways to tell the difference between tentacles and arms. The first is that tentacles can be retracted, while arms remain at the same length even though they can be folded.
Octopuses have three hearts, which is partly a consequence of having blue blood. Their two peripheral hearts pump blood through the gills, where it picks up oxygen. A central heart then circulates the oxygenated blood to the rest of the body to provide energy for organs and muscles. Like the three other members of the group — squids, cuttlefish and nautiluses — they have blue blood, because it uses a copper-rich protein to transport oxygen.
This helps explain why they need three hearts. But for a species as a whole, it results in major limitations. Not being able to pass on the wisdom gained by previous generations means a whole lot of learning gets repeated and rediscovered by each succeeding generation. The octopus is one of the few creatures that can regrow a completely severed or damaged appendage so that it is as GOOD as new and indistinguishable from the original.
A missing arm can be completely regenerated in roughly days. The Korean dish Sannakji features live baby octopus arms cut into pieces and served fresh and mobile. Those of us who know that each arm has a mini-brain of its own might think twice about trying to swallow a live octopus arm.
Even when an arm is severed from its body, the suckers will keep applying suction. This means that arms must be well chewed before swallowing, otherwise they will stick to the mouth and throat.
Apparently, an average of six people choke and die from wrapping their mouths around sannakji each year. Yes, a live octopus can kill you , especially if you are dumb enough to stick one into your mouth.
I love giving presentations to hundreds of guests on board cruise ships! Octopuses are one of my favorite topics. Monterey bay aquarium provides an excellent series of octopus videos that I can highly recommend. Zullo, L. Motor control pathways in the nervous system of Octopus vulgaris arm. J Comp Physiol A , — George Sranko, B. He has explored fascinating nature topics and epic destinations for over 40 years, beginning with his first job as a National Park naturalist. George is a popular destination and science lecturer on cruise ships throughout the world, with hundreds of presentations under his belt.
He has visited over 90 countries and happily shares his personal experiences and insights in a dynamic and entertaining style. Albatrosses are large seabirds with the longest wingspans of any bird in the world, up to 10 or 12 feet. As a biologist, I became intrigued with the flight of the albatross after watching huge Whenever I listen to the song of a Humpback whale, I am captivated by the eery quality of the complex sounds. Skip to content. Octopus, Bonaire.
Photo by Vlad Tchompalov on Unsplash Multiply this eight times for eight arms and we can see that the mini brains take a big load off the central brain.
0コメント