Why do octopuses have no bones? Living in the ocean, the animal doesn’t need bones. Instead of an octopus skeleton, they use buoyancy and extreme musculature in their arms to move, swim and manipulate heavy objects. The arm muscles work pretty much the same way the human tongue does.
How do animals move without bones? They’re called hydrostats or hydroskeletons and things like that. It basically has to do with having certain kinds of muscles oriented in certain ways, and then also having body fluids. And the water is not compressible like air would be, so the muscle is working against fluids. MF: Like hydraulics.
How does an octopus move? Octopuses move using jet propulsion—they suck water into their mantle cavity, then quickly contract their muscles to force the water out through a narrow siphon, aiming the water to steer in a particular direction.
How do octopus support and protect themselves without a skeleton? Unlike most molluscs, octopuses do not have hard shells to protect themselves. However, they are well equipped to look after themselves, and they can squeeze their soft bodies into tight spaces to hide from danger.