First off, there is no such thing as a "higher species;" species are either successful or they are not. Secondly it is not the size of the skull, but the size of the brain case in relation to the size of the body that paleontologists andzoologists use to deternime the relative intelligence of the critter in question. For instance, your average raptor (velociraptor, utahraptor, etc.) was a highly intelligent critter compared to other dinosaurs. It would've come across as a freakin' moron next to an ostrich, though.
It is interesting that in an attempt to bash me, you contradict the basis of your evolutionary theory with a silly semantic argument. According to evolution there is. Darwinists are great tree drawers and the latest species they call the higher species since they appear higher in their trees. Also evolution claims that complexity arose slowly with each succeeding species adding something.