  As to the first point, chimeras that are truly difficult to definitively classify as human or non-human are purely hypothetical. Even the chimeras involving the most extensive mixing to date (Goldstein et al. 2002; Muotri et al. 2005; James et al. 2006) resulted only in individuals easily classified as non-human animals. Such easily categorized individuals pose no more threat to our views about moral status than does a human being with a pig heart valve, that is, no threat whatsoever. Hence, the idea that such confusion is threatened by “any crossing of species boundaries involving human beings” (Robert and Baylis 2003, 10; emphasis added) is surely mistaken. And even if researchers were to create chimeras that were truly on the border between human and non-human, it still would not follow that there would be significant confusion as to the proper moral framework for their treatment. If the chimeras were clearly persons (by exhibiting a high degree of autonomy, rationality, self-awareness, etc.), then it would be clear to most people that they have full moral status, even if it would not be clear what species they were. As Andrew Siegel (2003, 33) notes, most people hold the belief that “species doesn’t matter where one possesses other traits that confer moral standing.” Those who do mistakenly believe that being a human being is necessary for full moral status might simply correct their mistaken belief when confronted with an actual example of a non-human or borderline-human that was clearly a person. Only the remaining people who retain that belief would be confused.