LAST year was a good one for jellyfish. More people than ever spotted these intricate, tentacled wonders in the seas around Britain and reported their findings to a citizen-science project run by the Marine Conservation Society. These sightings are showing that jellies are not exactly taking over the ocean, as stories of the ‘rise of slime’ would have us believe, but, as members of the public get to know these beautiful species, they’re helping to build a better picture of what’s actually going on with the gelatinous creatures.
Jellyfish are simple animals. They have no brain, only a basic net of nerves to control the movements of their soft, boneless bodies. They don’t have blood and no need for a heart to pump it around. Despite their delicate appearance, jellyfish are incredibly tough and successful—their ancestors began swimming around the ocean at least half a billion years ago. When conditions are good, they flourish and proliferate
