A group of Masai giraffes munch on leaves in Kenya's Masai-Mara National Reserve.

Denis-Hunot/NPL/Minden Pictures

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Counting Giraffes

Should we think of giraffes as one species or four?

JIM MCMAHON/MAPMAN

Spotting a giraffe while on safari is pretty easy. From its 6-foot-long neck to its distinct brown-and-tan pattern, you wouldn’t mistake one for a zebra. For years, scientists agreed that there was just one species of giraffe, with nine subspecies. But they’re now rethinking that definition. A new analysis of giraffe DNA suggests that giraffes should be regrouped into four separate species.

Spotting a giraffe while on safari is pretty easy. Giraffes have 6-foot-long necks and distinct brown-and-tan patterns. You wouldn’t mistake one for a zebra. For years, scientists thought that there was just one species of giraffe with nine subspecies. But a new study of giraffe DNA suggests that giraffes should be divided into four different species.

Biologists define a species as a group of living things that have similar features and can reproduce. Subspecies often arise when different populations are isolated and develop different traits. But they can still breed with other members of the same species. For example, a wolf and a domestic dog belong to the same species, Canus lupus, but are different subspecies.

To get a clearer picture of giraffes, biologist Axel Janke and his team at the Senckenberg Research Institute in Germany studied skin samples from 141 wild giraffes. The samples were collected by the Giraffe Conservation Foundation. When they compared key areas of DNA from the skin samples, four groups of closely related giraffes emerged. “The four giraffe species seem not to have bred with each other for a very long time,” says Janke. “Just like separate species.”

A species is a group of living things that have similar features. Only members of the same species can reproduce with one another. Subspecies form when different groups are separated and develop different traits. But they can still breed with other members of the same species. For example, a wolf and a pet dog belong to the same species but are different subspecies.

Biologist Axel Janke wanted to get a clearer picture of giraffes. He and his team at the Senckenberg Research Institute in Germany studied skin samples from 141 wild giraffes. The Giraffe Conservation Foundation collected the samples. After comparing key areas of DNA from the skin samples, the team found that there are four groups of closely related giraffes. "It looks like the four giraffe groups haven't bred with each other for a long time. Just like separate species,” says Janke.

Why does it matter if giraffes are one species or four? The way species are defined is important for legal protection and conservation. In the case of giraffes, there are fewer than 100,000 left in the wild—that’s more than 40 percent less than in the 1980s. Last December, giraffes were reclassified from a “species of least concern” to “vulnerable” because of habitat loss and poaching. 

But when the animals are split into four groups, the situation becomes even more urgent. Three of the four new species of giraffe would be considered under a more serious threat. “The world’s tallest animal is under severe pressure in some of its core ranges across East, Central, and West Africa,” says Julian Fennessy, a co-director of the Giraffe Conservation Foundation. “It’s time to stick our necks out for giraffes before it is too late.”     

Why does it matter if giraffes are one species or four? The way species are defined is important for legal protection and conservation. Today, fewer than 100,000 giraffes are left in the wild. That’s more than 40 percent less than in the 1980s. Last December, giraffes were reclassified from a “species of least concern” to “vulnerable” because of habitat loss and illegal hunting.

Giraffes are even more threatened if they’re four species instead of one. Three of the four new species would be more seriously threatened. Julian Fennessy is the co-director of the Giraffe Conservation Foundation. He warns that the world’s tallest animal is at risk across all of Africa. “It’s time to stick our necks out for giraffes before it is too late,” he says.

Use proportions to calculate how many of each subspecies of giraffe live in the wild. Record your work and answers on our answer sheet.

Use proportions to calculate how many of each subspecies of giraffe live in the wild. Record your work and answers on our answer sheet.

Lee Montgomery

Use these statements of proportionality to complete the chart above.  

Use these statements of proportionality to complete the chart above.

A. For every 2 West African giraffes, there are 10 Kordofan giraffes.

A. For every 2 West African giraffes, there are 10 Kordofan giraffes.

B. The ratio of Rothschild’s giraffes to West African giraffes is 4 to 1.

B. The ratio of Rothschild’s giraffes to West African giraffes is 4 to 1.

C. There are 6 South African giraffes for every 2 reticulated giraffes.

C. There are 6 South African giraffes for every 2 reticulated giraffes.

D. The ratio of Angolan giraffes  to South African giraffes is 10 to 7.

D. The ratio of Angolan giraffes  to South African giraffes is 10 to 7.

E. For every 12 Thornicroft’s giraffes, there are 13 Nubian giraffes.

E. For every 12 Thornicroft’s giraffes, there are 13 Nubian giraffes.

F. The ratio of Masai giraffes to Thornicroft’s giraffes is 160 to 3.

F. The ratio of Masai giraffes to Thornicroft’s giraffes is 160 to 3.

About how many giraffes would there be in each proposed new species?

About how many giraffes would there be in each proposed new species?

How do you think splitting giraffes into four species would affect conservation?

How do you think splitting giraffes into four species would affect conservation?

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