In a recent article “Abortion and Simple Consciousness' (Journal of Philosophy, V. LXXIV, N. 3, pp. 159–172), Werner S. Pluhar puts forward the following view:

A few words of explanation are in order. The reasoning can, I think, be summed up as follows: If one thinks that being conscious is what gives beings rights (and this seems to be a fairly common idea), then what justifies preferential treatment for humans as opposed to sentient members of other species? The fact, or so the answer goes, that humans have a higher degree of consciousness than do members of other species. But human fetuses do not have a higher degree of consciousness than, say, adult dogs. What justifies preferential treatment of human fetuses as opposed to adult dogs? The fact that human fetuses have a higher potential for reaching a higher degree of consciousness than do adult dogs. The liberal who holds that future generations have rights, e.g., to a healthy environment, thereby holds that merely potentially conscious beings have rights. If we have a right to life, then future generations also have that right. But fetuses are no less potentially conscious beings than unconceived future generations. So even a liberal must concede that if we have a right to life, fetuses have a right to life, and that it is at least prima facie wrong to destroy them by abortion.