Genetic analysis reveals that giraffes are in fact four distinct species.

How Scientists Realized “Giraffes” Are Really Four Distinct Species

How Scientists Realized “Giraffes” Are Really Four Distinct Species

The state of the universe.
Sept. 9 2016 6:28 PM

How One Giraffe Became More. Specifically, Four.

Actually, what we thought of as a “giraffe” is four different species. How did scientists miss this?

Giraffe.
But which giraffe?

Musat/Thinkstock

Astronomers are lucky. When they uncover something weird, like a planet orbiting our nearest neighboring star, they can say, “Yes, but that pinprick was 40 trillion kilometers away.” When biologists make similar discoveries that turn convention on its head, the general reaction is “How did you not notice this?” When that discovery suddenly revises our understanding of a 20-foot-tall animal that’s strewn throughout a sizable chunk of a continent and that can weigh up to 2,600 pounds, “No, seriously ... how did nobody notice this?!” is a pretty valid question.

That’s the question researchers from the Senckenberg Biodiversity and Climate Research Center and the Giraffe Conservation Foundation found themselves asking after they conducted some genetic tests and realized that what we’ve long thought of as “the giraffe,” is actually four distinct species. They’ve since renamed them, very creatively spinning off on the giraffe theme: the Masai giraffe, the reticulated giraffe, the southern giraffe, and the northern giraffe.

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For a long time, researchers and observers alike have noticed the visible variation between individual giraffes in features like color and coat pattern, but this had long been ascribed to simple diversity throughout the various subspecies. The researchers were originally checking in on the giraffe population’s genetic diversity in hopes of clearing up confusion over exactly how many subspecies of giraffe there are. (Giraffes have long been classified as one species, with anywhere from nine to 11 subspecies.) They were taken aback, however, when they found that the genetic material betrayed a much deeper split between various giraffes.

According to geneticist Axel Janke, who was part of the research group that published these finding in the journal Current Biology, “Some of the differences were as large or larger than the differences between brown bears and polar bears.” That is to say, all the giraffes, like all bears, could kill you if they got angry enough—but if you took the time to look closely while getting trampled, you’d notice a striking variance between coat patterns.

In all seriousness, though—what constitutes a new species? A distinct species is largely defined by the animals’ ability to produce viable offspring with each other. The paper notes that “wild giraffes are highly mobile and can interbreed in captivity,” which may explain why biologists assumed they were all the same species (just with slightly different spots). But it turns out that in the wild, these four distinct species of giraffe are “reproductively isolated,” and their genetics show distinction large enough to warrant listing them each as individual species. Janke notes the reason that this was never noticed before is likely in part because giraffes are not popular research subjects compared with other African megafauna like lions, elephants, and rhinos.

This research is bittersweet news for the giraffe conservation campaign. The population has long been in decline, having lost a third of its population over the past three decades, but is still classified as “least concern.” This discovery means that what was once thought as one population, with much diversity, is actually several, each with a much smaller gene pool than ever previously predicted. The hope of scientists like Janke is that such a find could go a long way in helping galvanize lawmakers to pay greater attention to the management of giraffe populations.

But of course, the main question we’re all wondering, besides what we can do to help protect and stabilize giraffe populations, is a simple one. That would be: “Which giraffe, is the giraffiest?” So far, we don’t know that much about the distinctions between the four giraffes, beyond where they live. But my money is on the reticulated giraffe, or G. reticulata, for the sound reasoning that any animal sharing a name with the reticulated python, is cool enough to be the real G.

An intelligence analyst–turned–science journalist, Ian Graber-Stiehl also writes for Popular Science and OZY.