The death of a 45-year-old rhino is rarely a tragedy; they seldom live much longer. Although Sudan’s passing was long expected, it still struck a blow to conservationists all around the world. Sudan was the last male of his species, and he leaves behind just two females in the entire northern white rhino population at the Ol Pejeta Conservancy in Kenya.
“Sudan was the last northern white rhino that was born in the wild. His death is a cruel symbol of human disregard for nature and it saddened everyone who knew him,” Jan Stejskal, director of international projects at the Dvur Králové Zoo, told Agence France-Presse.
There were some 500,000 rhinos across Africa and Asia at the start of the 20th century. But thanks to poaching and habitat lose, all but two rhino species (the Indian and the southern white, a lucky cousin of Sudan and his ilk) are endangered. The Indian rhino is still classified as Vulnerable, with the 20,000 southern white rhinos kept safe in protected areas and private game reserves considered “Near Threatened.”
Northern and southern whites are technically considered subspecies—not quite genetically distinct enough to be taken as a separate species—but this is a matter of some debate. Some evidence suggests they last shared a common ancestor around 1 million years ago (though other analysis suggests a much shorter period of estrangement). On the other hand, some conservationists say use of genetic analysis to declare so many subspecies is causing “taxonomic inflation.” Animals can grow quite different from their closest relatives when they’re isolated from other populations, but whether that means we should protect them as unique animals is a matter of debate. The white rhino is a perfect example. Taken as one singular species, it’s in no trouble at all; but the northern white is in dire straits indeed.
These may seem like needless quibbles—perhaps even insensitive ones to mention, given the recent death in the family—but the debate isn’t over just because Sudan is gone. His daughter Najin and her daughter Fatu are still alive, and with a lot of time, money, and effort, they could soon give birth to a new generation of northern white rhinos.
Thomas Hildebrandt, head of reproduction management at the Leibniz Institute for Zoo and Wildlife Research in Berlin, has been working for years to perfect in-vitro fertilization on the related and plentiful southern white in the hopes of harvesting eggs from one of the two remaining females. Neither of them is physically able to carry a calf, but should Hildebrandt successfully harvest their eggs, he can fertilize them with northern white sperm—taken from Sudan and three other deceased males—and implant the embryos in southern white surrogates. Calves could even arrive after the final two members of the species have died, which would mean an extinct species had been completely reborn with a scientific assist.
It’s quite the gambit, one that means poking and prodding at (and, eventually, impregnating) one subspecies at the expense of another. And speaking of expense, no one is quite sure how much it will cost. But researchers say this could be the only way to save an animal that fell not because of its own faults, but because of human folly.
“This is a creature that didn’t fail in evolution,” Hildebrandt told The New York Times. “It’s in this situation because of us.”
And while Sudan may be the last male of his kind, this is surely not the last time humanity will face the dying days of a once-majestic species.