giraffes
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Surprise! There are four species of giraffe, not one

Gerald couldn't dance; Abigail couldn't count; and Geoffrey was a klutz. Now, these gangly storybook giraffes, with their long necks, legs, eyelashes, and prehensile purple tongues, have to worry too about what species they are. A closer look at the genetics of Africa's giraffes suggests that Giraffa camelopardalis really represents four distinct species. With an estimated 90,000 browsing the savanna treetops, this charismatic animal is one that most conservationists have not been too worried about. But, if this new family tree holds up, one species numbers fewer than 5000 individuals, making it one of the world's more endangered mammals. The new classification came about after researchers from the Giraffe Conservation Foundation in Namibia collected skin samples from 190 giraffes throughout Africa. They asked researchers in Germany to analyze the DNA in these samples. Given how mobile giraffes are, one would expect a lot of interbreeding, so the researchers were surprised by how different the DNA could be—some genetic differences greater than those between a grizzly and a polar bear, which are separate species. Thus, the team reports online today in Current Biology that, based on their genetic differences, the continent's nine subspecies really break down into four true species that separated between 1.25 million and 2 million years ago. They may still interbreed, but group in these four genetically distinct categories. The new categorization divides these animals into the southern giraffe (G. giraffa), the Masai giraffe (G. tippelskirchi), the reticulated giraffe (G. reticulata), and the northern giraffe (G. camelopardalis). There are more than 40,000 southern giraffes, but fewer than 5000 northern giraffes, and given that the total giraffe population has dropped from 150,000 to about 90,000 in the past 30 years, northern giraffes could be in trouble in the near future, the researchers say.