Ol Pejeta raised millions of dollars into trying to get them to procreate. It’s a strange conservation paradigm that talks about animals in fences and cages. They did very well out of those rhinos.”Implications for white rhino conservationOthers like KeesRookmaaker of the Rhino Resource Center accept the new classification. “Groves is a respected taxonomist who has reviewed many species of mammals, which provides consistency of approach within the class,” says Rookmaaker. “Most taxonomists follow Groves’ approach. Some scientists feel that his taxonomy is unjustified. But when you study the papers, you will find that the genetics are very similar, but the conclusions differ. I think it is unfortunate, especially at a time when the white rhino of Central Africa is at a point of no return.”As a species, white rhinos are not endangered. At least 20,000 southern whites roam the expanses of southern Africa. If northern white rhinos were a separate species, their situation is extremely dire. If Sudan was the last male of a species, there is no hope for its survival. But if northern white rhinos are a subspecies, the outlook for their future is relatively less severe.Inbreeding between few individuals would cause maladapted mutations to spread to the detriment of the species. Lots of different individuals maintain genetic diversity that a healthy population needs. The future viability of the northern white rhino depends on interbreeding with southern white rhinos. This is difficult to pull off if they were considered separate species. For instance, Bengal tigers (Pantheratigristigris) breeding with ones from Sumatra (Pantheratigrissondaica) for conservation purposes would be acceptable since they are both subspecies. But the offspring of tiger and lion has no value for the conservation of either species.Should taxonomy – the study of classification of life forms – bend to the convenience of conservation?In 2016, Eric Harley and other geneticists from the University of Cape Town, South Africa, examined the mitochondrial DNA of the two white rhinos once again and concluded they were subspecies. The ancestors of the animals had separated not one million years ago as Groves and his colleagues estimated but more likely between 460,000 and 970,000 years ago. Such inconsistencies are bound to creep in when samples are drawn from few individuals.So what is a species? It depends on which of the 10 biological concepts one applies. According to one, if two distinct groups can produce offspring, they are the same species. Another says a geographically restricted population with distinct characters is a different species.Northern white rhinos produce offspring with southern white rhinos, vindicating the champions of subspecies status. However, polar bears (Ursusmaritimus) and grizzly bears (Ursusarctos) are two different species and yet produce fertile young. We don’t know if the hybrid young of white rhinos are fertile because only one was born at DvůrKrálové Zoo, which never bred.In 2017, Groves and a team of scientists from several institutions defended his previous effort to make the northern white rhino a separate species. They said they weren’t unnecessarily splitting species but correcting past oversight. Taxonomists of the 20th century had lumped several species together. Groves and others pointed to consistent differences in body size, length of bones and vocalisations of the northern and southern white rhinos to make their case. Also, the genetic work that Harley and others had done shows the two rhinos are ‘reciprocally monophyletic’, meaning northern white rhinos are more similar to each other than southern white rhinos.Emslie suggests looking at the species conundrum differently. “Many conservation geneticists are moving away from talking in terms of subspecies but instead favouring the use of Evolutionary Significant Units (ESUs) and Management Units (MUs),” he says. “In this case, the northern white rhinos and southern white rhinos would be considered separate ESUs and MUs. One usually wouldn’t mix MUs unless there was a good reason to.”With the lack of consensus on the subject, how should we view Sudan’s death? What does it mean for white rhino conservation?“It is indeed tragic and shameful that this is the second distinct rhino taxa that is going extinct under our watch,” says Fernando, who collaborated with Groves in declaring northern white rhinos a distinct species. “The last Vietnamese Javan rhino [a subspecies of the Javan rhino] was shot and killed by a poacher in 2010.”“It serves as a warning not to have all one’s eggs in one basket,” says Emslie. “If a second population had been set up two decades ago, there is a very good chance we would still have breeding northern white rhinos in the wild.”“Sudan’s death is symbolic,” says Elodie Sampere, a spokesperson for Ol Pejeta. “It signifies extinction. If we allow the second largest mammal on the planet to go extinct, what chances do smaller species have? We are currently facing extinction at a faster rate than any other time in human history. We must use Sudan’s death as a wake-up call for the rest of the species.”Ol Pejeta Conservancy’s press release on Sudan’s death included a call for donations:The estimated cost of IVF – from the development of the method, to trials, implantation and the creation of a viable breeding herd of northern whites – could be as much as US$ 9 million. Yet this is the hope for preserving an entire subspecies. Ol Pejeta and DvůrKrálové Zoo are asking supporters to donate towards this campaign in memory of Sudan, to help us raise the funds needed before it’s too late.In 2016, an article in Nature reported that San Diego Zoo had raised $2 million after it had lost all its northern white rhinos.“They talk like business people,” comments Ogada. “Conservation cannot be a business. Stewardship cannot be a business. This entire sob story is driven by money which is driven by crisis or the illusion of crisis.”Contested territory in the conservation of African wildlifeIs keeping a subspecies going at this cost worth the effort? Could this money not be put to better use for, say, the Javan rhino or Sumatran rhino?“First of all, there should be enough funds out there to do both,” says Sampere. “Why do we have to choose? And second, if we manage to bring back the northern white rhinos from the brink of extinction using science, this could mean that we could use the same technology for other species. We feel it is tremendously important to carry on.”“It is entirely right that our main priority should be to conserve remaining wild rhino in their natural habitats, and such high tech IVF work should not deflect effort and funds away from this,” says Emslie. “However, in this instance, I have been informed that the funding to sponsor the IVF ART [Assisted Reproductive Technology] research work on white rhino is coming from a source that would not be supporting wild field rhino conservation.”ButOgada is scathing in his dismissal. “There are white rhinos left in South Sudan, and in about a year or two, a ‘saviour’ (most likely Caucasian) will ‘discover’ them to much fanfare and acclamation.”There is a slim chance of a few northern white rhinos holed up in a remote part. Many of these areas are war zones and no one has explored them for many years. Besides, as conservationists noted more than three decades ago, aerial surveys may not be the best way to find rhinos.Two years ago, western biologists “discovered” a population of “lost” lions in remote parts of Sudan and Ethiopia. Residents of the area knew of the lions, but until foreign scientists saw them, they were not truly “discovered.” Or take the case of elephants returning to Somalia after 20 years. Such media promotion erasing indigenous experts and knowledge creates resentment among some African conservationists.“The story is – wildlife in Africa is in danger, and the threat is African people,” says Ogada. “The saviours of wildlife are white. This is the story that sells. There’s a complete diminution of African people. This individual rhino is bigger than a country. One television channel even said Sudan was instrumental in maintaining peace in all of Africa.”Ogada continues, “Sudan’s death means the end of a particular line of funding, sob story, and source of fame. There are two females left there, but the in vitro fertilisation attempts have nowhere near the gravitas or romance of a single remaining male. Bluntly put, the end of a hoax. For the rest of the world outside Ol Pejeta Conservancy, it is not worth any of the mourning or moaning!”More than an icon for a species or subspecies driven to extinction, Sudan has come to symbolise contested territory in the conservation of African wildlife.