if humans were to try to prevent predation, such as from stopping lions killing gazelles, that it would likely increase the "net amount of animal suffering", but asserted that if hypothetically we could reduce suffering in the long-term, then it would be right to intervene. The English philosopher Stephen R. L. Clark's "The Rights of Wild Things" (1979) is considered to be one of the first ethics papers to explicitly engage with predation as a problem. In the paper, Clark argues that the concept that humans are obligated to aid animals against predators is not absurd, but that it follows only in the abstract, not in practice. Animal rights philosopher, Tom Regan in his 1983 book, The Case for Animal Rights, argued that humans have no obligation to prevent predation because carnivorous animals are not moral agents and as a result cannot violate the rights of the animals that they predate. Along these lines, Julius Kapembwa argues that "intervention in predation is neither required nor permitted by animal rights theory". Steve Sapontzis, in his 1984 paper "Predation" argues against the idea that the problem of predation is a reductio ad absurdum for animal rights, instead, he claims that if we accept the view that we have an obligation to reduce avoidable animal suffering, then predation is something that we should work towards preventing if we can do so without inflicting greater suffering. Sapontzis concludes that whether humans choose to fulfil this particular obligation, or attempt to reduce other forms of avoidable suffering, is a question of where humans can do the most good. In a 2003 paper, the economist Tyler Cowen advocates, from a utility, rights and holistic perspective, for the policing of nature to reduce the predatory activity of certain animals to help their victims. The transhumanist philosopher David Pearce, in his 2009 essay, "Reprogramming Predators", claims that predation is an immense source of suffering in the world and that a "biosphere without suffering is technically feasible". He argues for the phased extinction of carnivorous species using immunocontraceptives or "reprogramming" them using gene editing so that their descendants become herbivores. Pearce lists and argues against a number of justifications used by people who think that suffering caused by predation does not matter and that it should be conserved in its current state, including a "television-based conception of the living world", "[s]elective realism" and "[a]daptive empathy deficits". In 2010, Jeff