UCC Lecturer published in National Geographic | Heather Steele

Professor John Davenport of the school of BEES has recently published a paper jointly with Roger Hughes, a colleague at the University of Bangor, on the mechanism of emperor penguin swimming.The pair noted a previously unstudied phenomenon in emperor penguins. The penguins utilise the power of bubbles to act as lubricant to cut drag and increase speed when swimming. So significant are the findings of their research that it has been published in National Geographic magazine. The research will also be featured in a BBC 4 programme on bubbles in 2013. This is the second success for the BEES department in recent weeks as research on deep sea vents as part of the ‘Alien Deep’ programme was shown on the National Geographic channel a few weeks ago.The pair began hypothesizing their theory over a pint in Hughes’ local pub. Hughes had assumed that Davenport would know the reason for the bubbles, but he too was stumped. “Roger thought I’d have the answer straightaway,” says Davenport.  It turns out that no one else knew what the bubbles did either. Along with senior researcher Marc Shorten of the Department of Zoology, Ecology and Plant Science at UCC the group began to look at the possibilities of the bubbles. With the help with of Poul Larsen, an engineer from the Technical University of Denmark, the team analysed hours of footage of the emperor penguins swimming. They discovered that the penguins were able to use air as a lubricant, something which engineers had been trying to do for years.When the penguins swim through the water they are slowed by the friction of their body and water. This means there speed is greatly reduced and they are more vulnerable to predators such as the leopard seal. But when it swims in short bursts its swimming speed is increased two to three-fold, allowing it to speed past any threat of danger. This is due to the fact that it can release air from its feathers in the form of tiny bubbles. This allows the penguins to reach incredible speeds which otherwise would be impossible.The reason the penguins can perform this amazing feat of aerodynamics is due to their feathers. Their feathers contain tiny filaments, less than 20 microns in diameter, which trap air which is then released as microbubbles. These microbubbles are then sufficiently small as to form a lubricating coat over the body of the bird which cuts friction substantially.The impact of this research is long-reaching and may be utilising by engineers as a method of increasing speed in large aquatic vessels. In 2010 a Dutch company began selling a system which lubricated the hulls of ships with bubbles.Professor Davenport’s research is printed in this month’s issue of National Geographic.