Transferring Morality to Human–Nonhuman Chimeras
Authors: Monika Piotrowska
Journal: The American Journal of Bioethics (2014)

Abstract Human–nonhuman chimeras have been the focus of ethical controversies for more than a decade, yet some related issues remain unaddressed. For example, little has been said about the relationship between the origin of transferred cells and the morally relevant capacities to which they may give rise. Consider, for example, a developing mouse fetus that receives a brain stem cell transplant from a human and another that receives a brain stem cell transplant from a dolphin. If both chimeras acquire morally relevant capacities as a result of transplantation, and if those capacities are indistinguishable, should the difference in cell origin matter to how we classify these creatures? I argue that if morally relevant capacities are easy to detect, cell origin is irrelevant to how the chimera ought to be treated. However, if such capacities are hard to detect, cell origin should play a role in considerations about how to treat the chimera. Keywords: chimerahuman neuron mousestem cellmoral statusoriginclassification ACKNOWLEDGMENTS Special thanks to Steve Downes, Matt Mosdell, Rosamond Rhodes, Jason Scott Robert, Robert Streiffer and two anonymous reviewers for their careful reading and constructive criticism. In addition, I would like to thank Ana Iltis for organizing the ASBH Mentor-Pairing Workshop in Washington, D.C. Notes 1. The human–mouse chimeras also showed greater fear. When trained to fear an innocuous tone by pairing it with foot shock, "the human glial chimeric mice exhibited a significant enhancement in learning of the tone foot shock association: they showed greater fear to the tone as measured by scoring freezing behavior (the cessation of all movement except for respiration)" (Han et al. Citation2013, 349). While efforts have been made to exclude chimpanzees from this category—by ending federal funding available for such research—chimpanzees may still be used in privately funded experiments when the research is considered necessary for human health (Gorman Citation2011). The relational argument is not always used to support anthropocentrism. A version of it has been used to prevent research on nonhuman animals that are closely related to humans. For example, when the U.S. government announced a halt on all new grants supporting research on chimpanzees, the reason provided was that chimpanzees are our closest relatives and therefore they deserve special consideration (Gorman Citation2011). Anthropocentrists need not be committed to Hull's particular account of species, but any view that accords special moral status to all and only human beings will most likely emphasize the importance of a thing's origin in establishing its species membership. It is worth noting that ethicists concerned with human– nonhuman chimeras acquiring "human-like" capacities (cf. Greely et al. Citation2007; Greene et al. Citation2005; Karpowicz et al. Citation2005) may at first glance appear to be advocates of the anthropocentric approach. After all, they are looking for traits that are human specific. However, unless they are interested in such capacities because they provide evidence for an underlying biological relation (a relation that is morally relevant on the anthropocentric view), they are not supporting anthropocentrism. Instead, they are supporting a capacity-based approach to moral classification. This will become clearer when I explain the capacity-based approach. Much of the following discussion on the complexities of genealogical relations is indebted to Piotrowska (Citation2012). Currently, this outcome is unlikely, since differences between species often constrain the development of human-nonhuman chimeras. I'll say more about this later. For yet another parallel case see Streiffer (Citation2005, 357). On the capacity-based view, capacities give us a reason not to harm a creature for its own sake, but there may be reasons other than for the creature's own sake not to harm it. Singer criticizes one version of the relational argument for anthropocentrism, but there are others. See Cynthia Townley's article (Citation2010) for criticism of three different relational arguments on the basis that each one is "either not restricted to humans, or is an inadequate basis for a difference in moral significance" (513). Although VanDeVeer's claims are counterfactual, there are a couple of reasons to be skeptical of the idea that steers are unable to remember the past. First, there is no evidence to support it, and second, in the 30 years since the publication of his paper, a number of studies have shown that mental time travel is a capacity that is not unique to humans (cf. Clayton et al. Citation2003; Corballis Citation2013; Eacott Citation2010). Depending on the circumstances, the capacity to anticipate the future may also decrease pain. For example, a creature capable of mental time travel may be able to anticipate a time when the pain is in the past, while a creature that lacks this capacity may have no choice but to be consumed by it.