With 1 male left worldwide, northern white rhinos under guard 24 hours

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Sudan is the only male northern white rhino left worldwide

Total of 3 northern white rhinos are left worldwide -- Sudan and two females

Experts trying various ways to save the subspecies, including in vitro fertilization

Ol Pejeta Conservancy, Kenya CNN  — 

A new study may hold the key to saving the northern white rhino’s rapid descent into extinction.

He grazes under the hot sun, his massive head lowered to the ground, at the Ol Pejeta Conservancy in central Kenya.

When he’s not napping in his enclosure, he waddles around the sprawling savannah, stopping briefly to drink water from a concrete hole.

But Sudan is not just any rhino. He’s the last known male northern white rhino left in the world.

For an animal on the verge of extinction, the fate of the subspecies rests on his ability to conceive with the two female northern white rhinos at the conservancy.

Sudan and the two female rhinos – Fatu and Najin – are the last three northern white rhinos left in the world.

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