An Asiatic cheetah in TehranCaren Firouz / Reuters

In 1947, as India was gaining independence from Britain, a maharaja in the mountainous state of present-day Chhattisgarh is said to have hunted down the last three Indian cheetahs. These cats have cultural links to the region dating back hundreds, if not thousands, of years: The word cheetah derives from the Sanskrit word citraka—“spotted one”—and in the 16th and early 17th centuries, the revered Mughal emperor Akbar kept more than 1,000 as his hunting companions. By the early 20th century, though, their numbers had shrunk, and in 1952 they were officially declared extinct on the subcontinent.

The Indian government has spent decades trying to bring cheetahs back. At first, conservationists imagined either importing or cloning Asiatic cheetahs, the subspecies that once thrived in India. When that strategy failed, they turned their attention to a closely related subspecies, found across Africa in pockets of the south, west, and east.

Both Asiatic and African cheetahs are sleek and elegant, with sand-colored coats covered in black spots, and black “teardrop” marks that run downward from their eyes. Asiatic cheetahs, however, are slightly smaller, and their coats a lighter shade. But those small distinctions mask fundamental questions about what defines a native species and whether one subspecies can be swapped in for another. In the past few years, a narrow scientific debate about cheetah genetics has become a question of legal import, reaching all the way up to India’s Supreme Court.

In 2012, as the court was hearing a case about the protection of India’s native lions, it learned about a government plan to bring African cheetahs into India. Ravi Chellam, the former director of the Wildlife Conservation Society of India and an expert witness in the case, argued that India should spend its limited conservation resources to improve the management of the species it currently has. “Should we be investing to conserve African species right now?” he asked. “Is that really a priority for us?”

The court agreed, ruling in 2013 that African cheetahs were a “foreign species … which never existed in India” and could not be legally introduced to the country. But now, because of a request from the Indian government, the Supreme Court is reexamining that injunction, and the cheetah has a new chance to return.

The government first failed to reintroduce cheetahs in the 1970s, when it considered a swap of Asiatic cats between India and Iran. Today, a critically endangered population of roughly 40 Asiatic cheetahs survives in Iran, but four decades ago, hundreds lived there. India, for its part, had several hundred Asiatic lions, which Iran wanted to reintroduce.

Before the trade could happen, though, India needed to develop a prey base for the cheetah. As the country’s grasslands were repurposed for agriculture, both the cheetah and its prey were pushed into suboptimal habitats, where they struggled to survive. Conservationists, including M. K. Ranjitsinh, India’s first director of wildlife preservation, saw this trade as the best chance to preserve not just the country’s cheetah legacy, but also the land where the cats once thrived. “In India, symbols are very important. In the name of the tiger, we saved something more valuable than the tiger: We saved the habitat of the tiger,” Ranjitsinh told me. “By that same token, I was hoping the cheetah could save our most productive ecosystems, the grasslands.”

Conservationists began work to increase populations of prey such as the blackbuck (Indian antelope) and the chikara (Indian gazelle). But talks with Iran fell apart after the Islamic Revolution of 1979.

The idea of reinvigorating India’s Asiatic-cheetah population had a second life, though. Twenty-two years later, in 2001, Lalji Singh, the “father of DNA fingerprinting in India,” came to Iran with a new proposition: Let his lab collect sperm and tissue samples from Asiatic cheetahs, in order to clone one. He planned to use an Indian leopard as a surrogate mother for the newly cloned cheetah cub. Iran rejected the approach, and the idea fizzled out.

With the Asiatic cheetah off the table, conservationists considered a new approach: introduce an African subspecies into India. Ranjitsinh and other experts believed that African cheetahs could sub in for the Asiatic as the top predator of the grassland’s food chain. In 2009, they organized an international conference in Rajasthan to discuss the idea with other influential conservationists. For that group, the prospect of redeveloping cheetah habitats in India was exciting; the species as a whole has lost approximately 90 percent of its former range and is classified as vulnerable.

One of the attendees was Stephen O’Brien, a geneticist who founded the Laboratory of Genomic Diversity at the National Cancer Institute. O’Brien had long been interested in animal genetics, and he was inclined to see African cheetahs as a suitable replacement for Asiatic ones. Since the 1980s, his research has advanced the theory that the cheetah genome, across subspecies, is remarkably uniform.

O’Brien attributes that uniformity to two genetic “bottlenecks,” or brushes with extinction. A small number of cheetahs—which evolved first in North America—survived the first bottleneck by crossing the Bering Strait into Eurasia and Africa more than 100,000 years ago. Their population rebounded until hitting the second bottleneck toward the end of the last Ice Age, 10,000 to 12,000 years ago, which wiped out most of the world’s large mammals. The cheetah lived but, O’Brien argues, emerged genetically limited, having resorted to inbreeding to survive. In this version of events, some subspecies diverged from one another as little as 5,000 years ago, and today the minute genetic variation in cheetahs is “like the amount of distance between the people of Baltimore and the people of Philadelphia,” O’Brien says.

Other experts disagree. The work of the conservation geneticist Pamela Burger and a team of researchers from the University of Veterinary Medicine in Vienna revealed “significant divergences” among different subspecies of cheetah and showed both Asiatic and Northeast African cheetahs to be genetically distinct from South African cheetahs. The theory of a 12,000-year-old genetic bottleneck is “not written in stone,” Burger says, and the bottleneck could have happened 40,000 years ago, giving subspecies more time to differentiate.

This seemingly esoteric argument over bottlenecks and subspecies has real consequences for the future of the world’s cheetahs. Introducing African cheetahs to India, where they would have another habitat in which to reproduce, could aid the long-term survival of the whole species. But substituting one subspecies for another risks erasing valuable genetic adaptations. Burger suggests, for example, that Asiatic cheetahs developed specialized traits that made them adept at living in mountainous regions.

The data produced by Burger and her fellow researchers intensified the call to save the remaining Asiatic cheetahs in Iran, but the results were also used in India to convince the Supreme Court that African cheetahs could not be substituted for Asiatic cheetahs. O’Brien says he does not believe that his work and Burger’s are in conflict, but rather that they interpreted the data differently. However, in 2017, he co-authored an unofficial rebuttal in the Journal of Heredity that said Burger’s research included “ambiguous and imprecise dating calculations,” which the Supreme Court relied on.

For her part, Burger believes her team’s data stand on their own and provide an “enlarged view” of the different cheetah subspecies. She’s not vehemently opposed to the introduction of African cheetahs in India, but explains, “It would be like having an African lion in a wild park in Europe. Of course, you can have that, but then it’s an African lion living in Europe. Not a European lion.”

This experiment—African cheetahs living in India—could still happen. At a hearing in early August, the Supreme Court suggested it might allow several African cheetahs to be translocated into India for a pilot program, potentially opening the door to a larger introduction of an African subspecies into India.

If the Supreme Court does allow African cheetahs into the subcontinent, the government would need to ensure that there was enough prey to sustain them, and enough room to minimize human-cheetah conflict. India has a mixed record when it comes to protecting its cats, however, and currently hundreds of Asiatic lions are languishing in a wildlife reserve, despite a 2013 mandate from the Supreme Court to move some of them to a secondary habitat in another state. Ritwick Dutta, an environmental lawyer who worked on those proceedings, calls cheetah reintroduction “a clear case of misplaced priorities” that diverts time and resources from the endangered species that already live in India.

But the conservationist Laurie Marker, who sequenced several complete African-cheetah genomes with O’Brien in 2015, says that if Indian authorities were willing to dedicate sufficient resources, “they would not be on their own.” Marker’s organization, the Cheetah Conservation Fund in Namibia, would likely help select suitable cheetahs for translocation to India. Cheetahs with the best chance of success would be those that don’t have a history of attacking livestock, are savvy to threats from stronger predators, and fit within certain age parameters. Marker is optimistic about the effort, provided that it’s handled correctly. “Cheetahs,” she says, “are very adaptable.”

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