Sea Starfish

Fascinating facts about the Sea Starfish

• A sea star can push its stomach out through its mouth, slide it between the shells of a mussel, and digest the prey outside its body — turning the mussel's home into an external dining room. This hydraulic feeding system works even on prey sealed shut so tight that the sea star's arms can't pry them open. It's a workaround 500 million years of evolution perfected.
• Lose an arm to a predator on Monday and by next spring you'll have grown it back, complete with new tube feet and sensory organs. Some species can regenerate from a single severed arm — the arm grows a new body around itself. The rebuilt limb is chemically identical to the original, yet we still don't fully understand how the sea star 'remembers' its shape.
• A sea star has no brain, no blood, and no heart. Instead of blood, seawater flows through its body in channels, delivering oxygen and nutrients. Instead of a brain, a nerve ring around its mouth makes decisions — which means a sea star tastes its way through life, every surface it touches is information.
• The crown-of-thorns sea star, a Pacific relative, can lay 65 million eggs in a single breeding season. When conditions align — usually after a storm stirs up nutrients — populations explode so densely they smother entire coral reefs, devouring 5 square metres of coral per year. A single animal can eat faster than a reef can rebuild itself.
• Sea stars navigate by chemical smell alone, following a scent plume upwind across the ocean floor to find food buried under sand or hiding in crevices. Their arms are lined with sensor cells that detect amino acids at concentrations so faint that a human couldn't smell them even if the Pacific Ocean were a swimming pool. They're living bloodhound noses with no eyes to second-guess the signal.

At a glance

About the Sea Starfish

As the tide recedes, a sea starfish slowly unfurls its delicate, almost translucent arms, stretching like ethereal fingers across the rocky shoreline. With a gentle, languid pace, it begins its patient crawl, leaving behind a trail of tiny, glistening footprints as it navigates the intricate, wave-sculpted landscape in search of its next meal. In this fleeting, sun-dappled world, the sea starfish is a quiet, unassuming monarch, its very existence a testament to the beauty and fragility of life in the ocean's intertidal realm.

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