- Huge sea mammals often dive underwater for over an hour for food
- Team of biologists say they have adapted protein myoglobin in their blood
- It becomes charged and is able to store more oxygen
By Steve Robson
|
The sperm whale is able to hold its breath underwater for up to 90 minutes because of a unique protein in its blood, an international team of scientists has discovered.
The huge mammal will often dive up to 3km deep under water for more than an hour in search of food.
The world record for the longest time a human has held their breath underwater is 19minutes which was set by Swiss freediver Peter Colat in 2010.
Gulp: The sperm whale is renowned for its ability to dive under water for long periods at a time in search of food
Unique: Biologists believe the sperm whale has an adapted protein in its blood which enables it to dive for so long
Biologists at the University of Manitoba and the University of Liverpool revealed today that they have identified a distinctive molecular signature in the oxygen-binding protein myoglobin.
Deep-diving mammals have a much higher concentration of myoglobin than land-based mammals such as humans.
But until now, little was known about how it is adapted in champion divers such as the sperm whale.
Biologist Kevin Campbell says that, essentially, the proteins become more electronically charged which forces them to repel each other.
This helps them carry more oxygen.
'The trick, it appears, is to evolve a protein with a strong positive surface charge,' he said.
'The resulting molecular repulsion allows the oxygen-storing myoglobin of divers to accrue in much higher concentrations.
'By mapping this molecular signature onto the family tree of mammals, we were able to reconstruct the muscle oxygen stores in extinct ancestors of today's diving mammals,' added team leader Michael Berenbrink from the University of Liverpool.
Theory: The biologists believe the whale's protein myoglobin becomes charged enabling it to store more oxygen
Scott Mirceta, who worked in both labs, added: 'We are really excited by this new find, because it allows us to align the anatomical changes that occurred during the land-to-water transitions of mammals with their actual physiological diving capacity.'
Mr Campell added that the myoglobin characteristic has even been found in the DNA of land-dwelling mammals which once lived in the sea.
He said: 'What's more remarkable is that telltale signs of this novel attribute remain in the DNA of terrestrial mammals with an aquatic ancestry, such as spiny echidnas, subterranean moles, and even elephants, for which an amphibious past has long been suggested.
Mr Berenbrink suggested that the evidence only strengthen long-held theories of evolution.
'This finding not only illustrates the strength of evolutionary theory, but, for the first time, allows us to put 'flesh onto the bones' of these long extinct divers,' he concluded,
It is hoped the research could help improve understanding of a number of human diseases where protein aggregation is a problem, such as Alzheimer's and diabetes.
How many did they kill to find out. - Davewhoever , Gloucester, 15/6/2013 00:21 Not enough
- Johnpinecone , Glasgow, United Kingdom, 15/6/2013 02:18
Report abuse