And there's another key difference, too: The primary component of octopus blood is hemocyanin, which incorporates atoms of copper, rather than hemoglobin, which incorporates atoms of iron. This is why octopus blood is blue rather than red. Octopuses are the only marine animals, apart from whales and pinnipeds , that demonstrate primitive problem-solving and pattern recognition skills. But whatever kind of intelligence these cephalopods possess, it's different from the human variety, probably closer to a cat.
Two-thirds of an octopus's neurons are located along the length of its arms, rather than its brain, and there's no convincing evidence that these invertebrates are capable of communicating with others of their kind.
Still, there's a reason so much science fiction such as the book and movie "Arrival" feature aliens vaguely modeled on octopuses. Octopus skin is covered by three types of specialized skin cells that can quickly change their color, reflectivity, and opacity, allowing this invertebrate to easily blend in with its surroundings.
Thanks to this arsenal of cells, some octopuses can make themselves indistinguishable from seaweed. A bit like an undersea sports car, the octopus has three gears. If it's in no particular hurry, this cephalopod will walk lazily with its arms along the ocean bottom. If it's feeling a bit more urgent, it will actively swim by flexing its arms and body.
And if it's in a real hurry say, because it has just been spotted by a hungry shark , it will expel a jet of water from its body cavity and zoom away as fast as it possibly can, often squirting a disorienting blob of ink at the same time.
When threatened by predators, most octopuses release a thick cloud of black ink, composed primarily of melanin the same pigment that gives human beings their skin and hair color.
This cloud is not simply a visual "smoke screen" that allows the octopus to escape unnoticed; it also interferes with predators' sense of smell.
Sharks , which can sniff small droplets of blood from hundreds of yards away, are especially vulnerable to this type of olfactory attack. Octopuses are carnivores, and the adults feed on small fishes, crabs, clams, snails, and other octopuses. They typically forage alone and at night, pouncing on their prey and wrapping it in the webbing between their arms.
Some octopuses use venom of varying levels of toxicity, which they inject into its prey with a beak similar to a bird's; they can also use their beaks to penetrate and crack hard shells. Octopuses are night hunters, and they spend some of their daylight time in dens, generally holes in shell beds or another substrate, vertical shafts sometimes with multiple openings.
If the sea floor is stable enough to permit it, they can be as deep as 15 inches or so. Octopus dens are engineered by a single octopus, but they can be reused by later generations and some species are co-occupied by male and female for a few hours. In laboratory situations, octopuses build dens out of shells Nautilus , Strombus, barnacles , or artificial terracotta flower pots, glass bottles, PVC tubes, custom blown glass—basically, whatever is available.
Some species have den colonies, clustered in a particular substrate. The gloomy octopus O. Gloomy octopus den groups are excavated into shell middens, a pile of shells built by the octopuses from prey.
Octopuses have very short lives, between one and three years, and they are dedicated to raising the next generation. Mating occurs when the male approaches the female: One of his arms, typically the third right arm, has a special tip called hectocotylus which he uses to transfer sperm to the female's oviduct.
Some of these females probably spawn in autumn, others might leave the coastal waters over the winter season and spawn in early spring, joining the animals of the first group.
A third group, consisting of immature animals, invades the shallow waters in late spring. While males mature during the summer, females are likely to depart to deeper waters and return to coastal areas in spring for spawning.
Doubtless, there is a vertical migratory movement in relation to spawning. Generally, the abundance of this species decreases with depth and is nearly zero at the continental shelf. Octopus vulgaris is normally solitary and territorial. Animals make their homes near to other octopuses of similar size.
If animals share a tank, each will try to occupy a home or settle down at some distance from the other inhabitants. This individualistic behavior is only interrupted during mating and spawning, but even then females brood their eggs in isolation. When not traveling in- or offshore, O. Underwater observations showed that the animals remain in their dens; they leave them at dusk for hunting trips and return at dawn.
Excursions during the day in search of food are of shorter duration. Some octopuses may occupy the same home for a longer period while others change holes several times over a few days. Octopus vulgaris is a typically nocturnal animal, not only in its normal habits but also in the laboratory. Octopus vulgaris are active predators that feed primarily on gastropods and bivalves.
Small hatchlings typically spend several weeks as active predators in the plankton before they settle down to the benthic mode of life at a size of about 0. In , some , tons of O. In , the number was , tons.
There is the potential for the overfishing of these animals, which threatens their proliferation. However, at this time, they are not at any specific risk. It is the second largest ocean in the world after the Pacific Ocean. Referring to an animal that lives on or near the bottom of a body of water. Also an aquatic biome consisting of the ocean bottom below the pelagic and coastal zones.
Bottom habitats in the very deepest oceans below m are sometimes referred to as the abyssal zone. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria. Coral reefs are found in warm, shallow oceans with low nutrient availability. They form the basis for rich communities of other invertebrates, plants, fish, and protists. The polyps live only on the reef surface.
Because they depend on symbiotic photosynthetic algae, zooxanthellae, they cannot live where light does not penetrate. In both cases reproduction occurs as a single investment of energy in offspring, with no future chance for investment in reproduction. Abbot, R. American Seashells. Van Nostrand Co. Altman, J. The behaviour of Octopus vulgaris Lam.
Inderwater Assoc. Hatanaka, H. Studies on the fisheries biology of common octopus off Northwest coast of Africa. Far Seas Fish. Kayes, J. Mangold, K. The female guards and cares for the eggs, aerating and cleaning them until they hatch. As soon as they hatch, the young are able to swim, eat, and produce ink.
The male parent dies soon after mating and the female survives only until her brood has hatched. An octopus will generally live for about one to three years, depending on the species.
Octopuses are spread throughout a large ocean area and are solitary, which makes it difficult to determine the status of their populations. They are not believed to be under threat, but they are sensitive to pollutants.
Scientists are still discovering new species of octopuses. Octopuses move using jet propulsion—they suck water into their mantle cavity, then quickly contract their muscles to force the water out through a narrow siphon, aiming the water to steer in a particular direction. Mather and R. Anderson, The Cephalopod Page.
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In 4 seconds , you will be redirected to nwfactionfund. The National Wildlife Federation. Classification: Invertebrate. Description The octopus is a marine mollusk and a member of the class Cephalopoda, more commonly called cephalopods. Range Octopuses are found in every ocean of the world and along every coast of the United States. Diet Newly hatched octopuses will eat small foods such as copepods, larval crabs, and sea stars. Life History The male initiates mating by approaching the female.
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