FUNCTIONAL INTERCONNECTIONS IN THE JAW APPARATUS OF CHAMELEONS AND THE EVOLUTION OF ADAPTIVE COMPLEXES

摘要

General trends of transforming the jaw apparatus in the phylogeny of Iguanian lizards (especially in chameleons) are considered. Cranial kinesis in chameleons is represented by hyperstreptostyly, which enables propalinal movements of the lower jaw when the tongue is projecting to capture a prey. The specific peculiarities of the chameleon's jaw apparatus (quadrate-pterygoidal and jugo-mandibular ligaments, structure and position of the quadrate bones, loss of the epipterygoid and M. levator pterygoidei and others) are internal adaptations (sensu Severtzov, 1939) in relation to the mechanism of prey catching by the tongue. The evolution of this mechanism played part as a key innovation (or macromorphosis) in the phylogeny of chameleons. Ontogenetic interconnections of the jaw apparatus characters represent adaptation correlations, the phylogenetic transformations of which correspond to biological coordinations. Evolutionary pathways in the development of correlations and coordinations in organisms are considered.