I could be wrong, but I think I owe the following observation to J.P. Moreland.
In short, it appears Peter Singer himself can’t escape the charge of specieism. That is, not only is his criterion for persohnood ad-hoc and arbitrary (he never tells us why certain value-giving properties are value-giving in the first place), it distinctly favors his own species. For example, why are self-awareness and rationality—distinctly human traits—the standards by which we evaluate all living things, including non-human animals? Why are those things value-giving rather than, say, having traits that favor alligators, such as powerful jaws and tough skin? It seems that Singer’s own standard is no less specieist than the pro-lifer's.