The Giraffe Conservation Foundation asked scientists to carry out a genetic analysis of giraffes in Namibia, southwest Africa, merely to understand how similar, or not, different populations were to each other, and how that could help in conservation efforts.
But the scientists uncovered something unexpected.
Though modern giraffes had long been recognized as a single species, Giraffa camelopardalis, divided into a few subspecies, the researchers found four distinct species.
“We were extremely surprised, because the morphological and coat pattern differences between giraffe are limited,” said study lead researcher Dr. Axel Janke, a geneticist at Germany’s Senckenberg Biodiversity and Climate Research Centre.
Following a comprehensive genetic analysis using the DNA from 190 giraffes, Janke and his team discovered that the four species of giraffe had been separated for 1 to 2 million years, “with no evidence of genes being exchanged between them.”
The four giraffe species are: the southern giraffe (Giraffa giraffa), the Masai giraffe (G. tippelskirchi), the reticulated giraffe (G. reticulata) and the northern giraffe (G. camelopardalis).
Genetic differences among the four species are comparable to those between polar bears and brown bears, according to Janke.
“We’ve clearly completely forgotten what a giraffe is,” he told the BBC.
Unfortunately, the researchers said they also uncovered a sobering reality. There are fewer than 8,700 reticulated giraffe in the wild and under 4,750 northern giraffe. “As distinct species, it makes them some of the most endangered large mammals in the world and require doubling of protection efforts to secure these populations,” said Dr. Julian Fennessy, co-director of the Giraffe Conservation Foundation, in a news release.
The International Union for Conservation of Nature does not consider giraffes an endangered species. According to the foundation, however, giraffe populations have declined by over 60 percent in the past three decades. There are now fewer than 100,000 giraffe in the wild.
Researchers said they hope the new study will propel giraffe conservation efforts, and will also equip conservationists to better protect the four giraffe species.
“This is an important finding that will enable conservation biologists to target their efforts and, perhaps, to come up with new conservation approaches in captivity or in the wild, based on the genetic similarities and differences between these groups,” one of the study’s authors, Matthew Cobb, told the BBC.
The researchers’ findings were published this week in the journal Current Biology.