Pinch #1 – Deep-Sea Gigantism

Deep-sea gigantism describes the tendency of marine invertebrates that live deep in the ocean to be significantly larger than their surface-dwelling relatives. A good example is the colossal squid – the largest specimen ever recovered was 4.5 metres long, with an eye 27cm wide (a standard issue football has a diameter of 22cm). Legend has it that its older brothers might snack on sperm whale. Why this size is appropriate in the depths is probably to do with temperature regulation. Larger bodies retain heat most easily because the surface area exposed, across which heat is lost, is relatively small compared to the volume of the body. This means the colossal squid can return less frequently to warmer areas than its smaller counterparts, and dedicate more time to being a terrifying predator of the deep. With an estimated 95% of the world’s oceans currently unexplored, deep-sea gigantism offers an unsettling prediction for the types of tentacular monster that might patrol them.