Taken from:
http://www.religioustolerance.org/hom_fixe1.htm Whiptail lizards, (Cnemidophorus neomexicanus) found in the American southwest, are all females. They reproduce by parthenogenesis. Unfertilized eggs develop, producing an exact clone of its mother. Even though no males exist, the females still exhibit sexual mating behavior(WITH FEMALES). Those that attract a partner have been found to produce more and healthier eggs.
So there.
Heather