The Brain and Sense Organs of the Earliest Vertebrates: Reconstruction of a Morphotype

摘要: Speculations on the nature of brain and sense organs in earliest vertebrates have traditionally been based two different strategies. One approach has to examine living hagfishes lampreys, with assumption that these taxa are primitive thus represent starting point vertebrate phylogeny (Worthington, 1906; Ariens Kappers, 1929; Heier, 1948; Stahl, 1977). This is confounded by considerable differences organization lampreys themselves, so a single pattern can not be recognized, it also ignores fact long evolutionary history during which many changes obviously occurred.