* Astronomy

Giraffe genetic secret: Four species of tallest mammal identified

It is a famous, gentle giant of the African savanna, but the giraffe's genetics have just revealed that there is not one species, but four.
Giraffes have previously been recognised to be a single species divided into several sub-species.
But this latest study of their DNA suggests that four groups of giraffes have not cross-bred and exchanged genetic material for millions of years.
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