Scientists investigate why obesity is good for polar bears
Steve Connor is the Science Editor of The Independent. He has won many awards for his journalism, including five-times winner of the prestigious British science writers’ award; the David Perlman Award of the American Geophysical Union; twice commended as specialist journalist of the year in the UK Press Awards; UK health journalist of the year and a special merit award of the European School of Oncology for his investigative journalism. He has a degree in zoology from the University of Oxford and has a special interest in genetics and medical science, human evolution and origins, climate change and the environment.
Thursday 08 May 2014
The secret of how the polar bear copes with a high-fat diet without getting a heart attack can be found in the creature’s genetic makeup according to scientists who have analysed the genome of the world’s greatest living land predator.
A study of the genomes of 79 polar bears from Greenland indicates that key genes enable the species to metabolise fats in the bloodstream and liver to prevent heart disease and the buildup of fatty deposits in the arteries and around the heart, a study has found.
A polar bear’s diet is rich in seal blubber and half of its own body weight is composed of fat. It has cholesterol levels that would result in furred-up arteries and cardiovascular disease if they were seen in humans, scientists said.
“For polar bears, obesity is a benign state. We wanted to understand how they are able to cope with that. The life of a polar bear revolves around fat,” said Eline Lorenzen of the University of California, Berkeley.
“Nursing cubs rely on milk that can be up to 30 per cent fat and adults eat primarily blubber of marine mammal prey. Polar bears have large fat deposits under their skin and, because they essentially live in a polar desert and don’t have access to fresh water for most of the year, rely on metabolic water, which is a by-product of the breakdown of fat,” Dr Lorenzen said.
The study, published in the journal Science, compared the genomes of the polar bear and its closest living relative, the brown bear. The analysis indicates that polar bears evolved from brown bears about 500,000 years ago and quickly became specialists in eating a high-fat diet, who was essential for surviving almost solely on seal blubber.
- 1 PlayStation and Xbox hacked by Lizard Squad
- 3 The Grace Dent Christmas Questionnaire
- 4 The 'Black Museum': After 150 years, public set to see exhibits from police’s grisly crime museum
- 5 Vagina canoe artist defends herself over ‘obscenity’ charges
PlayStation and Xbox hacked by Lizard Squad
Antonio Martin shooting: Black teenager may have tried to ambush patrolman, says police officer's lawyer
Boxing Day snowfall set to push even more bargain-hunters online for sales
Katie Hopkins speaks out on childhood obesity: 'Parents of fat children should be prosecuted for child cruelty'
The 'Black Museum': After 150 years, public set to see exhibits from police’s grisly crime museum
British actor Idris Elba cannot star as James Bond because he is black, says shock jock Rush Limbaugh
Rozanne Duncan: Ukip expels councillor for 'jaw-dropping' comments made in BBC TV interview
Germany anti-Islam protests: 17,000 march on Dresden against 'Islamification of the West'
Ukip member gets into Christmas spirit with Union Flag plea to Santa 'for our country back'
BBC director Danny Cohen: Rising UK antisemitism makes me feel more uncomfortable than ever
Alex Salmond has 'broken his word to the Scottish people' says Scottish Lib Dem leader
£40000 - £43000 per annum + benefits: Ashdown Group: Senior Marketing Executiv...
£40000 - £43000 per annum + benefits: Ashdown Group: An international organisa...
£25000 - £30000 per annum: Ashdown Group: Internal Recruiter -Rugby, Warwicksh...
£70000 - £75000 per annum + benefits: Ashdown Group: Marketing Manager/Marketi...