When was the first octopus discovered

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. 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. 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. Inspired by the phenomenal camouflage ability of octopuses and cuttlefish , researchers have recently engineered a synthetic skin that mimics the function and design of the papillae, creating a stretchy material that can be programmed to transform into 3D shapes.

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. 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.

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This becomes highly advantageous when conserving oxygen is important. The cephalopods are a diverse class of mollusks a group that also includes snails and bivalves that emerged during an explosion of animal diversity in the oceans during the Cambrian period, over million years ago mya. Today, scientists divide the living cephalopods into three groups, called superorders. However, many details of cephalopod evolutionary classification continue to change as scientists find new clues from genetic testing and newly discovered fossils.

The cephalopods are a diverse class of mollusks. Many details of cephalopod evolutionary classification continue to change as scientists find new clues from genetic testing and newly discovered fossils.

Like the living nautilus, a fossil cephalopod shell has two distinguishing characteristics: a series of chambers divided by walls but connected by an internal tube. The barriers that separate the chambers are called septa and the internal tissue tube is called the siphuncle. There are many more species of fossil cephalopods 17, than living ones about and some of the most important groups in the past have no living descendants.

Early cephalopods probably diverged from the monoplacophorans, a group of bottom-dwelling molluscs with tall, slightly curved, conical shells. The first of these early cephalopod ancestors is likely Tannuella , a mollusk with a chambered shell. However, the first confirmed cephalopod fossil is the Plectronoceras, noted by the presence of a siphuncle used for control of buoyancy.

It is likely the acquisition of buoyancy that spurred diversification from these ancestral molluscs, since cephalopods were freed from a bottom-dwelling existence and could explore the open water column. By the Ordovician, a period that began roughly mya, a great diversity of cephalopod shells emerged. The stout, slightly curved shell shapes of the late Cambrian evolved into a variety of shapes that included coils, straight cones and domes.

Throughout much of the cephalopod's ancestry, the coiled shell evolved time and time again from a straight shell. A coiled shape strengthens the shell, increases maneuverability, increases the ability to cut through the water, and lowers the energy required to maintain buoyancy. The sluggish and armored cephalopods were likely no match for the new, swift swimmers. Not only were they competing for the same food sources, they were also likely a great snack.

These fast swimmers flourished following the loss of dinosaurs during the KT mass extinction roughly 66 mya. Remarkably, coiled cephalopods in the nautiloid group survived the extinction, but the coiled ammonites did not fare so well. Some scientists argue that the acidic ocean waters following the extinction-causing meteor crash dissolved the delicate shells of baby ammonites that lived near the ocean surface, and the deeper dwelling cephalopods remained out of harms way.

With a lineage that extends to around mya, it should be no surprise that the cephalopod family tree is pretty complicated. There are so many lineages and types of fossils that even cephalopod specialists often debate how they are related.

Below, are a few of the best-known groups of ancient cephalopods. The Nautiloids The Nautiloids are one of the oldest groups of cephalopods, emerging at the end of the Cambrian roughly mya. Throughout time, over 10, different species swam in the ocean, though today only the seven species of chambered nautiluses remain.

Though the earliest nautiloids had straight shells, by the Ordovician , which began roughly mya, their shells began to diversify, some becoming gently curved and others coiling. One way scientists distinguish the nautiloid fossils from their coiled cousins the ammonoids by looking at the siphuncle. In the nautiloids it is found directly down the middle of the chambers while in the ammonoids it hugs the outer shell wall.

The Ammonoids Ammonoids are a group of extinct, coiled cephalopods that swam in the ocean between and 66 mya between the Devonian and Cretaceous. Some were as small as a thumbnail while the largest measured over eight feet 2. Ammonoids also differed from the nautiloids in that the septa dividing the shell chamber joined the outer shell wall in intricate, undulating edges.

The septa-shell edge is called a suture, and as the ammonoids evolved the suture became increasingly intricate. This complexity may have helped with buoyancy control, while the more basic sutures of early ammonoids helped withstand the pressure of deep water.

It is possible that early ammonoids lived in deep water and over time they moved into shallower waters. The Belemnites The belemnites swam in the ocean from the end of the Triassic to the Cretaceous roughly to 66 mya and are one of the more studied straight-shelled cephalopods.

Based upon a few, rare soft-body fossils, they were squid-like and relied on jet-propulsion, with a straight internal shell and a pair of triangular fins. However, most of what we know about them comes from their shells—most belemnites had a solid tip beyond the chambered shell called a rostrum that was easily fossilized.

Belemnites were tasty meals for sharks and icthyosaurs. Many shark fossils contain the arm hooks of belemnites in their stomachs, but the noticeably absent rostrum is presumed to be too difficult to digest and most likely was regurgitated. Octopus are famous for their sophisticated intelligence; some scientists even argue that cephalopods were the first intelligent being s on the planet. They are able to untie knots, open jars, and toddler proof cases, and are generally expert escape artists.

There is increasing evidence that cephalopods have unique personalities—one octopus may be shy and reclusive, another curious and playful, or possibly mischievous and cranky. Perhaps, being defenseless, with soft bodies and living in a competitive environment with stronger, more agile bony fish led them to evolve especially sharp minds for problem-solving.

Intelligence requires big brains. A cephalopod brain is divided into many different sections called lobes. The squid Loligo has at least 30 different lobes. The lobes are specialized centers that, among other things, process information from the eyes, control camouflage, and store memories. Though structured similarly to other mollusks, a cephalopod nervous system far surpasses the nervous systems of their closest molluscan relatives—the California sea slug has about 18, neurons while the common octopus, Octopus vulgaris , has roughly million neurons in its brain.

Humans have many more, just under billion , but a cephalopod is on par with dogs and some monkeys since they also carry about two-thirds of their neurons in their arms, not their head. Unlike humans and other mammals, the cephalopod brain will grow one and a half times its original size from the moment of birth to adulthood. With intelligence comes the ability to learn.

Scientists first realized cephalopods had a talent for learning after the publication of a groundbreaking study by a German researcher named Jakob von Uexkull in Uexkull starved a group of octopuses for fifteen days and then presented them with hermit crabs carrying anemones on their shells. The famished octopuses readily attacked the hermit crabs, though after a few stings from the anemones they soon avoided the crabs altogether. Early studies found an octopus can be trained to perform specific behaviors using food rewards and shock punishments, showing they are capable of making associations.

When presented with a foreign but harmless object they will initially explore and investigate, but after consecutive introductions, they quickly lose interest, a sign they remember the object and its now unremarkable nature.

Surprisingly, though, octopuses are not the best when it comes to tackling mazes—they fail to even remember a simple sequence of turns. Levers are also tricky for octopuses and, for the most part, tests trying to teach octopuses to feed themselves using a lever mechanism have been unsuccessful. It may come as a bit of a surprise that although they are reclusive and solitary creatures, octopuses may be able to learn from one another. In a study, scientists trained a group of octopuses to discriminate between two colored balls.

Choosing a red ball elicited a tasty snack while choosing a white ball elicited an unpleasant shock. As this group of octopuses learned to associate color with reward and punishment, a second group of octopuses was allowed to observe from separate tanks.

Next, these observers were given the choice—red or white. Without reward or punishment, the second group chose the red ball more quickly than the initial group. Playing behavior is also attributed to intelligent organisms like mammals and some birds, but recent studies suggest octopuses may also like to have a little fun. A study at the Seattle Aquarium found that two of ten octopuses squirted water at weighted pill bottles, pushing the bottles against a filter current. After waiting for them to float back the octopuses squirted them again, almost like bouncing a basketball.

A study suggested that octopuses will play with blocks as well. Sometimes referred to as the chameleons of the sea, a cephalopod can change the color and texture of its skin in the blink of an eye.

Some use this skill to blend into their environment as masters of disguise, while others purposefully stand out with a flashy display. They change texture by controlling the size of projections on their skin called papillae , creating surfaces ranging from small bumps to tall spikes.

A study on cuttlefish found that once the papillae extend they become locked in place, enabling the cuttlefish to effortlessly hold their textured disguise while expending minimal energy. The color transformations are made possible by thousands of pigment-filled cells that dot the entire body, called chromatophores.

Within each chromatophore is an elastic, pigment-filled sac that is connected and controlled by several muscles and nerves. When the muscles contract the sack expands, revealing vibrant pigments—reds, browns, and yellows. When the muscles relax, the sack shrinks back down, hiding the pigment. The iridophores lie directly beneath the chromatophores and are responsible for displays of metallic greens, blues, gold, and silver.

In combination, these color and texture changing techniques allow a cephalopod to mimic almost any background. Experiments by Roger Hanlon show cuttlefish expertly mimicking mottled textures, stripes, spots, and a black and white checkerboard! Certain cephalopods have even mastered the ability to impersonate other animals, a self-defense tactic called mimicry. The mimic octopus is the pinnacle of shape-shifting wizardry. It appears to imitate up to 15 different animals that we know of.

Faced with a pesky damselfish it buries six of its arms in the sand leaving just two strategically placed and colored to look like the venomous banded sea snake a predator of the fish. It can also cruise along the sand like a flat, banded sole fish or swim up in the water column like the venomous, spiny lionfish. Light is created through a chemical reaction that produces light energy in the body of the animal, similar to how fireflies flash on a hot summer night.

A catalyst called luciferase sets off the light producing substance called luciferin. The result is an eerie glow, startling flash, or syncopated blinking. Bioluminescence serves more than just a pretty display. The concentration of photophores on the bottom side of some squid suggests the light is used as a camouflage technique called counterillumination; the bright light protects the squid from lurking predators below by allowing it to blend in with light coming from the surface of the water.

But for the cephalopods that want to stand out, light is used to lure prey or flash as a warning for predators. The dazzling light displays of the firefly squid during mating season off the coast of Japan are quite the sight to see at night, though scientists are unclear whether the purpose of the light is to attract mates, deter predators, or something yet to be discovered. One of the most exciting light displays is performed by the vampire squid. Deep ocean dwellers, vampire squid rely on three types of light organs.

Each of the eight arms is tipped with several simple light organs, tiny photophores dot the skin, and a third, more complex pair of light organs with photoreceptors sit near the fins. When startled, luminescent clouds of mucus are emitted from the arm-tip light organs, leading scientists to think the glowing display is a defense mechanism.

While some cephalopods, like the vampire squid, are able to produce light on their own, for others lighting up requires a bit of help. The bobtail squid relies on a bacterium called Vibrio fischeri , and will selectively allow this bacterium to grow within its photophores. At birth, a young bobtail squid lacks the bioluminescent bacteria and must find the light producing microbes in the water column.

Once one bacterium successfully enters the photophore it multiplies by the hundreds of thousands, a colonization that spurs the full development of the photophore. Vibrio fischeri is a common bioluminescence partner with some other cephalopods that owe their glowing skills to the microbe. In a stressful situation, a cephalopod has one final defense tactic. Almost all cephalopods have an ink sac, a bladder that can suddenly release a plume of dense, black ink.

When startled or attacked by a predator the ink jet works like a smokescreen, a distraction, or a cephalopod look-a-like that the predator attacks instead which allows the real cephalopod to make a quick escape. The ink can also act as a warning cue to other cephalopods. In the presence of ink the California market squid will begin to swim, and the Caribbean reef squid will initiate camouflage coloring.

The Japanese pygmy squid has figured out how to use ink to hunt for shrimp , rather than just hide from predators. It squirts a few quick puffs in the direction of the shrimp and then darts through the ink to grab its meal.

The ink is potentially used as a way to both hide from the prey and to distract the shrimp from noticing the incoming attack. For most cephalopods, sex is a once in a lifetime event—both the male and female die shortly after mating.

A male sometimes initiates the interaction with a courtship display meant to attract and woo the female, though for most octopuses there is little foreplay. If successful, the male will use his hectocotylus, a specialized arm, to deposit sperm packets called spermatophores on or in the female. The story of how the name hectocotylus came to be is a tale of mistaken identity.

Turns out, it was actually a male cephalopod arm, but the name stuck.