Jellyfish the first vortex and pushes the animal forward, but the mesoglea is so elastic that the expansion is powered exclusively by relaxing the bell, which releases the energy stored from the contraction. Meanwhile, the second vortex ring starts to spin faster, sucking water into the bell and pushing against the centre of the body, giving a secondary and "free" boost forward. The mechanism, called passive energy recapture, only works in relatively small jellyfish moving at low speeds, allowing the animal to travel 30 percent farther on each swimming cycle. Jellyfish achieved a 48 percent lower cost of transport (the amount
Lion's mane jellyfish lion's mane jellyfish. This was later corrected – in 1864, a bootlace worm ("Lineus longissimus") was found washed up on a Scottish shore that was long. ("That" claim has its critics: because bootlace worms can easily stretch to several times their natural length, it is possible the worm did not actually grow to be that length.) Lion's mane jellyfish The lion's mane jellyfish, also known as the giant jellyfish or the hair jelly, is the largest known species of jellyfish. Its range is confined to cold, boreal waters of the Arctic, northern Atlantic, and northern Pacific Oceans. It is common