How Did The Giraffe Stick Its Long Neck Out Forever?
By sequencing the genome of the giraffe for the first time, scientists have revealed some DNA aspects that explain how the tallest animals on earth cultivated their long necks.
Being a giraffe is a long haul, and you have to stick your neck out for some unnecessary problems. Imagine pumping blood two metres up from the chest to the brain calls. It calls for a "turbo-charged heart" and doubles the blood pressure of other mammals. Giraffes also require particular safety valves that can let them lean down to a source of water for a drink, and then raise their heads again without fainting.
Most biologists, including Charles Darwin, have found the unique and complex bodies quite baffling.
The mystery has been solved to some extent, as the scientists have compared the genome of the giraffe with its closest relative, the short-necked okapi. Scientists have pinpointed alterations in a small portion of the genes that regulates the shape as well as circulation of the bodies.
Hence, developing a long neck as well as a strong heart was a simultaneous exercise, which was driven by some genetic changes.
"There are many theories about how the giraffe's neck lengthened but it does seem that the development of the cardiovascular system evolved in parallel with the development of the skeletal system," said Morris Agaba of the African Institute for Science and Technology in Tanzania.
Examining the genetic factors behind the giraffe's exceptional cardiovascular system can give a clue to the strength of human health too. The animals seem to keep away from the sort of organ damage that is found in patients with high blood pressure.
Still, why exactly did the giraffes evolve their long necks?
Earlier, scientists said that it helped them to reach food that was high, out of reach. However, later theories stated that it is due to sexual selection and competition among the males of a species.
They have seven vertebrae like all mammals, but the bones are elongated and extended.
With his team, Agabe published the findings in the journal Nature Communications on Tuesday.
