>> For the first time, scientists have sequenced the genome of a giraffe, revealing how it developed its long neck. The work involved comparing the sequence with that of its closest relative, the short necked okapi, according to Reuters' Ben Hirschler.>> That has shown that there are small differences in a small number of genes that affect both the stature of the giraffe and its cardiovascular system.
And that suggests that the two things developed in parallel.>> Giraffes have a super-powerful heart capable of pumping blood two meters up to its brain and special safety valves to let it bend down to drink and raise its head again without fainting. The research may have benefits for humans.
A giraffe's blood pressure is twice that of other mammals but with none of the organ damage that people would suffer. But we still don't know why their necks are so long.>> For a long time, it's always been thought self-evident that it was to reach the higher, juicier leaves at the top of trees.
But in fact, they don't actually feed that much at the top of trees, and that's led to an alternative theory that it might actually all be to do with sex and sexual competition between the males for the females.>> High-tech science is starting to unravel one of the oldest puzzles in the natural world.