Creatures of the Deep | Life | BBC Documentary Series. Episode 8

Marine invertebrates, the descendants of one billion years of evolutionary history, are the most abundant creatures in the ocean. In the Gulf of California, packs of Humboldt squid make night-time raids from the deep to co-operatively hunt sardines. Beneath the permanent Antarctic sea ice of McMurdo Sound, sea urchins, red sea stars and nemertean worms are filmed scavenging on a Weddell seal pup carcass.