Unfortunately, the reports of their size are often exaggerated since finding a live giant squid is an extremely rare event. Almost everything people know about giant squid comes from specimens washed up on beaches. Sometimes their tentacles or arms have fallen off, or have been eaten by other animals while afloat in the ocean.
On the other hand, when they wash ashore, the squids can be bloated with water, appearing bigger than they really are. Because tentacles and arms fall off or, alternatively, can be stretched out, scientists often use mantle length as the best measure of a squid's actual size. The longest mantle length on record is 7. A new method for figuring out how big a squid can get includes using beak size to estimate total body length, a helpful tool considering the hard beaks are often found in the stomachs of sperm whales.
Based on this new method scientists believe the giant squid could reach lengths up to 66 feet 20 meters long, making it potentially larger than the colossal squid, however, a real-life squid of this size has never been documented. But does a big giant squid necessarily mean a strong one? If they were proportionally as strong as their smaller cousins, the Humboldt squid Dosidicus gigas , giant squid would be VERY strong, says Smithsonian squid expert Clyde Roper. However, that doesn't make them sluggish weaklings.
They have thousands of suckers working in unison on eight arms and two tentacles, with a rapidly-contracting mantle, to help capture and kill prey. The giant squid is not just a single species -- or is it? Some researchers think there are as many as 8 species in the genus Architeuthis Greek for "chief squid" , each a different kind of giant squid. But other researchers think there is just one Architeuthis that swims in the world's ocean.
There is no consensus because the squid are so hard to track and there are so few specimens available for study. However, it is certain that Architeuthis has an abundance of evolutionary relatives. The ocean holds an estimated species of squid—and almost all of those are in the same taxonomic order as the giant squid, called Oegopsina. Some are surprisingly tiny—only about 1 inch 2.
Others are impressively large, including the colossal squid Mesonychoteuthis hamiltoni , which can grow to be even bigger than the giant squid, reaching 45 feet 14 meters. These squid species are closely related to snails, clams, and even slugs: they are all mollusks , which are defined by their soft bodies. Some of these soft bodies are encased in hard shells, such as clams and snails, but not the squids.
Squids belong to a particularly successful group of mollusks called the cephalopods , which have been around for about million years. Some ancestors of modern-day squids had shells, such as the ammonites , which ruled the waves million years ago.
Of those that are still around, one small group—the nautiluses—has an external shell. The other—which includes squids, cuttlefishes, and octopods—does not, although squids and cuttlefishes have an internal, backbone-like support made of chitin called a pen.
Shell or no shell, all cephalopods have well-developed brains and are very active, jet-propelling themselves through the ocean. Most have ink sacs. And many can change skin color and texture in the blink of an eye. Giant squid are thought to swim in the ocean worldwide, based on the beaches they've washed upon, as shown in the map via Wikimedia Commons.
However, they're rarely found in tropical and polar areas. They commonly wash up on the shores of New Zealand and Pacific islands, make frequent appearances on the east and west sides of the Northern Atlantic, and the South Atlantic along the southern coast of Africa. How long does it take to grow so big? Unlike mammals, including people, and many fish species, cephalopods grow very quickly and die after a short life. Evidence from statoliths a small mineralized mass that helps squid balance , which accumulate "growth rings" and can be used to measure age, suggests that giant squid live no more than five years -- which means each squid must grow incredibly quickly to reach 30 feet in just a few years!
To grow at such a rate, giant squid must live in areas of the ocean where there is an abundant supply of food to provide enough energy. Smaller than the head of a pin, this arrow squid Doryteuthis plei embryo looks like a miniature adult and is almost ready to hatch! Depending on the squid species, the development from a fertilized egg to a nearly-hatched larva can take one or several weeks. Talk about pressure! Giant squid males don't use a modified arm hectocotylus to transfer sperm like most squid; instead, the spermatophore sperm packet is expelled from a penis, which sticks out through the funnel and can be as long as the animal's mantle, up to 7 feet long.
Not only is it the largest invertebrate on Earth, it also has the largest eyes of any animal, larger even than those of the great whales. With such limited opportunities for study, it is difficult to characterize the biology and ecology of such a rare species, even one as large as the colossal squid.
Reaching combined body and tentacle lengths up to 46 feet 14 m and weights of at least pounds kg , the colossal squid is a very large deep-sea predator.
Like in many large species, all the largest individuals are female. They eat small and large fishes including the Patagonian toothfish and other squids. The beak has an upper part and a lower part, like that of a parrot, but with the lower part overlapping the upper one the parrot's is the other way around. The strong, sharp beak slices through the prey's flesh, reducing it to small pieces that pass into the buccal bulb — a mass of muscle that operates the beak. The food is further shredded by the rows of teeth on the radula, and the teeth that line the palatine palps.
The chopped-up food goes through the narrow oesophagus throat which passes through the doughnut-shaped brain, then it goes into the stomach and caecum, where it is digested. The life and habits of a colossal squid How the colossal squid feeds How the colossal squid swims Bioluminescence in the deep ocean.
How the colossal squid feeds The colossal squid is a predator, and it hovers in the dark depths of the ocean looking for prey. Effective predator No one has ever seen a colossal squid catching prey.
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