Complex sentence: The behaviour of domestic pigs is more like that of dogs and humans, rather than cattle or sheep; in many ways, their behaviour appears to be intermediate between that of carnivores and the more highly evolved artiodactyls.
Split into simpler sentences: The behaviour of domestic pigs resembles that of dogs and humans more than that of cattle or sheep. In many ways, their behaviour appears to be intermediate between that of carnivores and the more highly evolved artiodactyls.