The notion of a linear Scala naturae in vertebrate brain evolution meanwhile has been replaced by the phyletic (cladistic) method of establishing ancestral and derived brain characters. From this analysis, a Bauplan or morphotype of the vertebrate brain emerges which exhibits many common ancestral neural traits (e.g., cranial nerves, brain subdivisions). Modern functional neuroanatomy and chemoarchitecture of fish brains confirm this view of a largely conservative neural organization throughout the vertebrate neuraxis on which many specializations may be detected. For example, ascending sensory pathways into the telencephalic pallium, motor output systems, as well as modulatory systems (dopamine, noradrenaline, serotonin, and acetylcholin) of lampreys, cartilaginous, and actinopterygian fishes share many commonalities still present in tetrapods. Hagfishes also have many of these vertebrate traits, but they lack external eye muscles and their innervating cranial nerves, as well as a cerebellum, indicating a simpler brain Bauplan for craniates.