A.N.Severtzov Institute of Ecology and Evolution, 117071 Moscow, Leninsky pr., 33

Abstract

All extant orders of amphibians are characterized by kinetic skulls. Main type ofintracranial movability in amphibians is pleurokinetism, that is supplemented in differentamphibian groups by various types of rhyncho- and prokinetism. The most primitive patternof cranial kinesis is revealed in the stegocrotaphic gymnophions. More paedomorphic speciesretain genera] cranial flexibility that is characteristic of larval skull. That is infavourable forevolution of well regulated (adult) cranial kinesis and related feeding adaptations. Kinetismis also reduced in the species with heavily ossified skulls. Adaptive role and evolution ofcranial kinesis in amphibians are discussed.