Crustaceans

Such crabs have specially evolved to a more compact size so that they can hide in the nooks and small spaces within the coral reefs.

However, as coral reefs are being progressively lost worldwide (by as much as 80 percent in the Caribbean), these crabs risk losing their homes.

This conclusion was reached after Post Doctoral Associate Dr Adiël A. Klompmaker and his team compiled the body size measurements of 792 species of prehistoric crabs and lobsters, and concluded that habitat appears to be a factor in the evolution of crustacean size.

Investigating deep waters off Bahamas, US-based researchers recorded the glow of tiny bioluminescent species using a submersible vehicle.

Descending to sites between 600 and 1000m down, the scientists observed flashes of bioluminescence where plankton collided with boulders and corals.

The team also studied how crustaceans react to this light, and found previously unknown sensitivities to blue and ultra violet wavelengths.