Spare a thought for taxonomists. Their job is to separate life into groups, from the great kingdoms of plants to animals, all the way down to individual species. Sometimes they have an easy job. For example, brown bears are easy to distinguish from polar bears. Other times, the differences are harder to find, such as spotting the difference between giraffe species.
Recently, a team of scientists took skin samples from 190 giraffes. Within each skin sample was a giraffe’s unique DNA. As DNA determines a living organism’s features and is passed down through the generations, it can reveal a hidden history.
For giraffes, the DNA results were surprising. Although the samples were all clearly related, they were different enough to be considered four distinct species. Previously, it was believed giraffes formed just one species.
The team estimates that giraffes split into these different species between one and two million years ago. That’s a long time! As a comparison, a study into bear species found less than half a million years separating brown bears from polar bears.
This recent discovery is important for conservationists. There are lots of giraffes in the wild, but some species are more common than others. This research will help rangers and scientists make sure all four giraffe species are safe from extinction.
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