For quite some time, giraffes were all thought to belong to a single species that was divided into several sub-species. However, as it turns out, we've not been entirely accurate about the world's tallest land animal from the very beginning.
In a recent study published in the journal Current Biology, it has been revealed that, rather than one species of giraffe, which is split up into several sub-species, there are actually four species of the animal, mirroring the genetic differences observed in polar bears and brown bears.
"We were extremely surprised," said conservationist Julian Fennessy, co-founder of the Giraffe Conservation Foundation and lead author of the study. He also noted that the conservation implications are immense, and that their findings will hopefully help put giraffe conservation on the map.
To be fair, there were already indications that all of these giraffes could be different species, but there was nothing distinct enough about them that would definitively prove it.
For example, the reticulated giraffe of Somalia, with its polygonal, liver-colored spots, can be easily distinguished from the Rothschild's giraffe of Uganda and Kenya, with patches that are not as sharply defined. Similarly, while the Rothschild's giraffe and Masai giraffe of Kenya and Tanzania are similarly marked, a close look at their skulls reveals that the former has five ossicones rather than the usual three — in fact, this feature is unique to the Rothschild's giraffe.
However, it wasn't until the Giraffe Conservation Foundation was looking into the potential results of different giraffe subspecies mixing together when they're moved into protected areas, that they realized there was more to giraffes than just their looks.
Following a process that took almost seven years, during which time 190 tissue samples were collected, an analysis of nuclear genetic markers and mitochondrial DNA revealed that giraffes can effectively be divided into four species: the southern giraffe (Giraffa giraffa), which has a population of about 52,000; the Masai giraffe (Giraffa tippelskirchi), with an approximate population of 32,500; the reticulated giraffe (Giraffa reticulata), which numbers to about 8,700; and the northern giraffe (Giraffa camelopardalis), with about a 4,750 population.
While monumental, the discovery also revealed something rather disconcerting: the reticulated giraffe and northern giraffe are in a rather precarious position. Though not considered endangered, they are dangerously close to that point, and these results should encourage the International Union for the Conservation of Nature (IUCN), which classifies giraffes as a single species, to take a stronger stance in their protection.
"Northern giraffe number less than 4,750 individuals in the wild, and reticulated giraffe number less than 8,700 individuals — as distinct species, it makes them some of the most endangered large mammals in the world," Fennessy said in a press release.
Fennessy said the biggest threats to the giraffe population include destruction of their habitat due to human population growth as well as poaching for bush meat, tail hair and "medicinal" parts.