Department of Chemistry

What guitarfish and aircraft wings have in common

Wed May 04 17:10:00 BST 2016

Recent research by a team led by Jonathan Cox and Zhijin Wang shows how water flows through the nose of a guitarfish, a type of ray. The team discovered that vortex-like structures in their noses help the guitarfish to swim and smell more efficiently. This is the first time that vortex-like structures have been found in a fish’s nose.

Guitarfish. Credit: Matt D. PotenskiSmell is important for fish. Their ability to pick up scent depends on the movement of water. Some fish get water moving through their nose by breathing, others by swimming.

The team discovered that guitarfish move water through their nose by swimming and breathing. The movement by swimming is helped by nasal flaps.

Vortex-like structures

These nasal flaps create regions of high and low pressure. Vortex-like structures resulting from the pressure difference may encourage water flow through the nose. This may make the guitarfish smell—and swim—more efficiently.

Schematic of hypothetical vortex ring formed in the left nasal region of Rhinobatos lentiginosus.The vortex-like structures in the guitarfish's nose may be similar to the vortex rings associated with aircraft wings. These vortex-like structures caused by air circulating near the wing enable planes (and birds) to fly.

Worldwide collaboration

The project was supported by the Alumni Fund and was a true collaborative effort. The team included marine biologists at a research station in the Great Barrier Reef and scientists from the Natural History Museum in London, as well as two undergraduate students from the Department of Mechanical Engineering here in Bath.

One of the undergraduate students, Mawuli Agbesi, said: 'It's a fascinating project, I'm not surprised engineering students try to get involved every year.'