Crabs can't swim all that fast, so nature has granted them defensive traits that make them the impenetrable forts of the underwater world. Their steel-tough exoskeletons have jagged points that make ...

Chameleon of the sea? Above left, octopus sees crab; right, octopus eats crab. You can see how the octopus changes color through its interaction with the crab, said Tiffany Boothe of the Seaside ...

A diver has captured a dramatic video of a crab squaring up to an octopus on the seabed in Australia. The video sees the blue-ringed octopus crawling along the seabed before encountering the crab, ...