Related BBC sites

Page last updated at 11:36 GMT, Wednesday, 26 January 2011
Seahorses' body shape explained
By Victoria Gill
Science and nature reporter, BBC News

Advertisement

A seahorse's shape enables it to suck in more distant prey

The strange and beautiful seahorse has fascinated people for centuries.

And scientists now say they understand why this unusual fish evolved its equine-like head and S-shape.

A study published in the journal Nature Communications has shown that, compared to straight-bodied pipefish from which they evolved, seahorses are able to strike at more distant prey.

The team concludes that the seahorses' delicate curves evolved to help it hunt and feed.

They attach to seagrass and wait for food to pass by within striking distance
Sam Van Wassenbergh
University of Antwerp

Both seahorse and pipefish feed on tiny marine creatures, striking at them and sucking them into their snouts.

But unlike most pipefish, which swim towards their prey, seahorses sit and wait for their little victims to pass by.

Using high-speed footage and mathematical models, Sam Van Wassenbergh from the University of Antwerp in Belgium showed that the curve in a seahorse's "neck" allows it to strike at more distant prey.

"They rotate their heads upward to bring their mouth close to the prey [passing above]," explained Dr Wassenbergh.

The creatures' curved bodies mean that when they do this, their mouths also moved forward, helping to bring passing small crustaceans within sucking distance of their snouts.

"My theory is that you have this ancestral pipefish-like fish and they evolved a more cryptic lifestyle," said Dr Wassenbergh.

Ghost pipefish and long-snouted seahorse (Image: Science Photo Library)
Seahorses evolved from straight-bodied pipefish (left)

This shift in the behaviour to become a more "sit and wait feeder" meant that they needed to capture prey that was further away, he explains.

So these new fish then became S-shaped seahorses, which could use their bodies to strike out.

"They grasp with their tail, to attach to seagrass and wait for food to pass by within striking distance," he says.



Print Sponsor


SEE ALSO IN EARTH NEWS
Dining table for hungry seahorses
21 Jan 11 |  Edinburgh, East & Fife
Cuttlefish lays eggs on seahorse
26 Mar 10 |  Earth News
Seahorse 'hitchhikes' Atlantic
18 Nov 09 |  Earth News
Ghostly 'dance of a sea dragon'
29 Oct 09 |  Earth News
Fragile seahorse habitats at risk
09 Sep 08 |  Science & Environment

OTHER RELATED BBC LINKS

MOST POPULAR STORIES

From Science/Environment in the past week

  • SATURDAY :
  • FRIDAY :
  • THURSDAY :

BBC navigation

BBC © 2014 The BBC is not responsible for the content of external sites. Read more.

This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.

Americas Africa Europe Middle East South Asia Asia Pacific