BBSRC-funded scientists have uncovered how the world's highest flying bird is able to survive in low oxygen environments, offering insights into low oxygen medical conditions such as heart attacks and strokes.
Researchers tested how well bar-headed geese were at coping with exercise in reduced oxygen environments by locally simulating the conditions of Mount Everest and getting the birds to run as fast as possible on a treadmill.
Exercising at high altitude is a massive challenge since at the top of the highest mountains the air is only made up of 7% oxygen, compared with 21% at sea level. This is why human climbers often use supplemental oxygen when scaling the world's tallest peaks.
They discovered that the geese had a remarkable tolerance of low oxygen conditions at rest and while they were exercising for 15 minutes at top speed - at oxygen levels that would render most humans completely immobile. The researchers also conducted the experiments with the barnacle goose, which migrates at sea-level, finding that they did not have the same ability in low oxygen conditions.
The study was led by Dr Lucy Hawkes at the University of Exeter, with colleagues Dr Charles Bishop at Bangor University and Professor Pat Butler at the University of Birmingham.
Dr Lucy Hawkes, at the Centre for Ecology and Conservation at the University of Exeter's Penryn Campus, said: "The wider implications of these findings are for low oxygen medical conditions in humans, such as heart attack and stroke - suggesting what adaptations might help prevent problems in the first place and learning how animals have managed to cope with really extreme environments.
"It all seems to come down to how much oxygen bar-headed geese can supply to their heart muscles. The more they can supply, the faster they can beat their hearts and keep the supply of oxygen to the rest of the body going. This suggests that other species, including humans, are limited more by what our hearts can do than by how fit the rest of our muscle are at altitude."
Bar-headed geese and barnacle geese undertake similar long distance migratory flights between breeding and wintering grounds, usually covering thousands of miles, during the autumn and spring. Bar-headed geese travel from Indian wintering grounds and high Asian breeding grounds in China and Mongolia, which means that they have to cross the Himalayan Mountains en route while flying as high as 7,290m (23,917ft).
The animals have been shown to possess a number of specific physiological adaptations that may increase their performance relative to other species of geese when exposed to severe environmental hypoxia (inadequate oxygen supply). In particular, their heart and locomotor muscles contain more blood vessels.
Notes to editors
The article, 'Maximum running speed of captive bar-headed geese is unaffected by severe hypoxia' by Lucy A Hawkes, Patrick J Butler, Peter B Frappell, Jessica U Meir, William K Milsom, Graham R Scott & Charles M Bishop was published on April 7 in the journal PLOS ONE.
About the University of Exeter
The University of Exeter is a Russell Group university and in the top one percent of institutions globally. It combines world-class research with very high levels of student satisfaction. Exeter has over 18,000 students and is ranked 8th in The Times and The Sunday Times Good University Guide league table, 10th in The Complete University Guide and 12th in the Guardian University Guide 2014. In the 2008 Research Assessment Exercise (RAE) 90% of the University's research was rated as being at internationally recognised levels and 16 of its 31 subjects are ranked in the top 10, with 27 subjects ranked in the top 20. Exeter was The Sunday Times University of the Year 2012-13.
The University has four campuses. The Streatham and St Luke's campuses are in Exeter and there are two campuses in Cornwall, Penryn and Truro. In a pioneering arrangement in the UK, the Penryn Campus is owned and jointly managed with Falmouth University. At the campus, University of Exeter students can study programmes in the following areas: Animal Behaviour, Conservation Biology and Ecology, English, Environmental Science, Evolutionary Biology, Geography, Geology, History, Human Sciences, Mathematics and the Environment, Mining and Minerals Engineering, Politics and International Relations, Renewable Energy and Zoology.
The University has invested strategically to deliver more than £350M worth of new facilities across its campuses in the past few years; including landmark new student services centres - the Forum in Exeter and The Exchange at Penryn - together with world-class new facilities for Biosciences, the Business School and the Environment and Sustainability Institute. There are plans for another £330M of investment between now and 2016.