How do jellies swim?
Jellyfish mostly drift with the currents, but they can swim to move short distances or redirect themselves. By contracting muscles in their bell, water is forced out and the jelly is propelled in the opposite direction. The muscles then relax and the bell gently springs back into its “open” position. This pulsing motion closely resembles an umbrella being closed and opened. At the cellular level, jellyfish muscles look almost identical to human muscles, but their “muscles” are only one-cell thick!
