unexplained-events:

Deep-Sea Gigantism (abyssal gigantism)

In zoology, deep-sea gigantism, also known as abyssal gigantism, is the tendency for species of invertebrates and other deep-sea dwelling animals to be larger than their shallower-water relatives.

Food scarcity, lower temperatures, and reduced predation pressures are all considered to be contributing factors to deep-sea gigantism.

Top Left: A Japanese spider crab whose outstretched legs measured 12 ft      (3.7 m) across

Top Right: A robust clubhook squid, whose mantle reaches 2 m (6.6 ft) in length, caught off Alaska.

Middle:  A 7 m (23 ft) king of herrings oarfish, caught off California.

Bottom Left: A giant isopod (Bathynomus giganteus) may reach up to 0.76 metres (2.5 ft) in length.

Bottom Right:  A Colossendeis colossea sea spider, displayed at the Smithsonian.

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