Giraffes are easily one of the most curious looking creatures to have ever roamed Earth. Resembling a horse sculpted into distortion by Salvador Dali, this tallest living terrestrial mammal has long been thought to only belong to one species – Giraffa camelopardalis – with nine subspecies declared to be wandering around the African continent.
Now, writing in the journal Current Biology, a genetic analysis has completely blown this concept apart.
“We found that there are not only one, but at least four genetically highly distinct groups of giraffe, which apparently do not mate with each other in the wild,” coordinating researcher Axel Janke, a professor of bioinformatics at Goethe University in Frankfurt, said in a statement.
Defining species in this way, although occasionally troublesome, is fairly clear-cut. Subspecies definitions are far vaguer, but tend to focus on superficial differences within species.
As an example of this, the nine giraffe subspecies were categorised based on coat patterns, horn structures and geographical distribution. The G. c. giraffa, found towards the very south of the continent, appears somewhat different from the G. c. peralta subspecies, which saunters around the Sahel regions of West Africa.
This new genetic analysis has turned this idea on its head, with four subspecies having been “upgraded” to species rank and some disappearing altogether.
The first is the southern giraffe (G. giraffa), comprised of the Angolan (G. g. angolensis) and South African giraffe (G. g. giraffa) subspecies. The second is the Masai giraffe (G. tippelskirchi) with no subspecies. The reticulated giraffe (G. reticulata) also has no subspecies, but the northern giraffe (G. camelopardalis, the “original” species) has three – the Nubian (G. c. camelopardalis), West African (G. c. peralta), and the Kordofan giraffe (G. c. antiquorum).
Image in text: The distribution of the now-defunct subspecies of giraffes around the African continent. IUCN/Wikimedia Commons; CC BY-SA 3.0