The extensive sampling includes populations from all nine previously recognized giraffe subspecies. Today’s study was the first to conduct a thorough genetic analysis on all nine subspecies of giraffe, and the tests clearly showed that there are four genetically distinct species of the creature. This means there are at least four different groups of giraffes who are genetically distinct and don’t breed with each other – the definition of a species.
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The study is particularly important for the conservation of the giraffe. “With now four distinct species, the conservation status of each of these can be better defined and in turn added to the IUCN Red List”, Julian Fennessy, a biologist with the Giraffe Conservation Foundation and co-author of the paper, said in a press release.
“If the findings of the current study are accepted, then it may well be that some species would be listed in threatened categories on the IUCN red list”.
Up until now, it was believed that there was only one, which was divided into a number of sub-species depending on the giraffe’s geographic origin.
Conservation was the catalyst for this genetic research; the Giraffe Conservation Foundation asked the team to carry out genetic analysis of giraffes in Namibia. The Giraffe Conservation Foundation estimates the southern giraffe population at 52,000 animals and the Masai giraffe at 32,500.
The new analysis looked at DNA markers in the genomes of 105 individual animals and found that the DNA sequences in those markers differ for each of the four species.
However, assessments of African elephants by the International Union for Conservation of Nature treat the animals as one species, due to concerns that splitting them into two species would place forest and savannah elephant hybrids into a kind of conservation limbo.
“The conservation implications are vast and our findings will hopefully help put giraffe conservation on the map”, Fennessy said.
Further research led them to the discovery of different fur patterns and coloration, which made them spot wild giraffes populations as separate groups.
This composite image shows members of the four different giraffe species.
Fennessy: The DNA tissue samples were collected through a variety of means, primarily remote biopsy darting, sampling of wild giraffe that had been captured for translocations or Global Positioning System satellite collaring, and sampling from deceased individuals. Dr. Janke had rarely seen such a large amount of genetic differentiation within a species, and this intrigued him. The formerly recognized subspecies Rothschild’s giraffe (G. c. rothschildi) turned out to be genetically identical with Nubian giraffe, and thus should be synonymized with this subspecies. That is about 40 percent less than 15 years ago. There are fewer than 8,700 reticulated giraffe in the wild and under 4,750 northern giraffe.
These are the Masai giraffe (G. tippelskirchi), the reticulated giraffe (G. reticulata), the southern giraffe (Giraffa giraffa) and the northern giraffe (G. camelopardalis).
The Reticulated giraffe (G. reticulata) also is a new species. “It puts into perspective how little we know about giraffes”, Janke says.
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Researchers have discovered there are not just one but four distinct species of giraffe, overturning two centuries of accepted wisdom in a finding that could boost efforts to save the last dwindling populations.
