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Contrasting squids
Contrasting squids




onyx carries their eggs around in a mass. Instead of anchoring them to the bottom, however, G. A species called Gonatus onyx spends most of its time in shallow waters, but descends to depths of some 8,000 ft/2,500 m to lay some 2,000 to 3,000 eggs. In contrast to the at least one species of squids brood its eggs. This is the first substance found in marine creatures shown to trigger aggression. Similar proteins are found in other animals, including mammals, although their function is not clear. Male squids are drawn to the eggs visually, but touching them – and the protein – has the effect of transforming them into lean, mean fighting machines, ready to take on any other male squids who might get near the eggs. Studying longfin squid reproduction ( Loligo pealeii), researchers discovered that the outer tunics of squid eggs are embedded with a protein called Loligo microseminoprotein. When a female squid deposits her capsules on the seafloor, she also imbues them with a protein that essentially drives male squids crazy – not about her but about the eggs. To ensure species survival, they produce them in the thousands. Their eggs are attractive as food for fish and other predators, as well.

contrasting squids

They’re favorite prey for many ocean denizens – sharks, bony fish like jacks, whales, dolphins, eels and sea snakes. Each capsule holds up to 200 eggs.īeing a squid makes for a tricky life. Squid egg masses are communal, meaning that more than one squid will contribute eggs. The females then plant them in clusters, consisting of two-inch-long, finger-shaped gelatinous capsules, deposited on the seafloor or attached to algae or other features. Within a female, special glands assist in nutrient manufacture and shell formation for the newly fertilized eggs. In many shallow water species, the gonoduct for doing so is short and the male uses a specially adapted arm to place the spermatophore within the cavity. Squid reproduction is a complex process that involves fertilization following the transfer of a male squid’s sperm – in the form of a single bundle called a spermataphore – into a female’s central mantle cavity for fertilization.

contrasting squids

Remember Kirk Douglas battling the giant squid in 20,000 Leagues Under the Sea? It’s could be like that. S OMETIMES, DURING DIVES, YOU ENCOUNTER THESE THINGS attached to the bottom. Squid eggs photographed at Plum Cove on Massachusetts’ Cape Ann.






Contrasting squids