Seahorses have a super strong sip thanks to two spring-like tendons
Seahorses have an unusually powerful way of swallowing their prey, and we now know how they do it. They feed in a rapid sucking motion powered by two spring-like tendons that simultaneously trigger an upward head sweep and a gulp of water. This allows small, otherwise slow-moving fish to capture prey in one lightning-fast motion.
The world’s fastest animal movements, from the snapping mandibles of a trap-jaw ant to the mighty punch of a mantis shrimp, are powered by spring mechanisms. Like firing a crossbow, the animal’s muscles pull the tendons into a locked position before releasing the tension in an explosive movement.
Researchers already knew that seahorses have an elastic tendon at the back of their heads that pushes their snouts up when they feed, but King Holzman at Tel Aviv University in Israel and his colleagues found that this would not be enough to account for the shear suction power that small fish can generate.

Seahorses use a spring motion to quickly capture their food
Shutterstock/Azahara Perez
In a comparison between three seahorse species and 10 other fish that lack a source-feeding mechanism, they found that seahorses could swallow water about eight times faster than expected for their size. blocked.
To try to identify how this was possible, the researchers illuminated a seahorse while it was feeding, allowing them to better see through its semi-translucent skin. They then spotted a second tendon, this one under the chin, which could provide the extra boost.
“We could see that the tendon is contracting, which means it can store elastic energy,” says Holzman. “It’s cool because until now we didn’t really know of an elastic energy storage mechanism that serves dual purposes,” he says, describing the simultaneous pushing of head and water.
“This supports well the hypothesis that not only rapid snout movement but also food aspiration is performed by these fish at very high power,” said Sam Van Wassenberg at the University of Antwerp in Belgium.
Next, Holzman plans to investigate whether seahorse species have different elastic feeding mechanisms depending on their size and prey. “I’m sure they have other crazy innovations that we haven’t found,” he says.
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