Craniate with well-defined heads, thus excluding members of the chordate subphyla Tunicata (tunicates) and Cephalochordata (lancelets), but including Myxini, which have cartilaginous skulls and tooth-like structures composed of keratin. Craniata also includes all lampreys and armoured jawless fishes, armoured fish, sharks, skates, and rays, and teleostomians: spiny sharks, bony fish, lissamphibians, temnospondyls and protoreptiles, sauropsids and mammals. The craniate head consists of a brain, sense organs, including eyes, and a skull. In addition to distinct crania (sing. "cranium"), craniates possess many derived characteristics, which have allowed for more complexity to follow. Molecular-genetic analysis of craniates reveals that, compared to less complex
Deception in animals There are relatively few examples of animal behaviour which might be attributed to the manipulative type of deception which we know occurs in humans, i.e. "tactical deception". It has been argued that true deception assumes the deceiver knows that (1) other animals have minds, (2) different animals' minds can believe different things are true (when only one of these is actually true), and (3) it can make another mind believe that something false is actually true. True deception requires the deceiver to have the mental capacity to assess different representations of reality. Animal behaviour scientists are therefore wary of interpreting