The braincases of mosasaurs and Varanus, and the relationships of snakes

Citation
O. Rieppel et H. Zaher, The braincases of mosasaurs and Varanus, and the relationships of snakes, ZOOL J LINN, 129(4), 2000, pp. 489-514
Citations number
73
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Animal Sciences
Journal title
ZOOLOGICAL JOURNAL OF THE LINNEAN SOCIETY
ISSN journal
0024-4082 → ACNP
Volume
129
Issue
4
Year of publication
2000
Pages
489 - 514
Database
ISI
SICI code
0024-4082(200008)129:4<489:TBOMAV>2.0.ZU;2-9
Abstract
The braincase structure of the mosasaur Platecarpus is described in detail and compared to that of Varanus and snakes. The braincase of mosasaurs and Varanus is found to be closely similar in most respects other than the cons equences of obliteration of the metakinetic axis in mosasaurs. Neither Vara nus, nor mosasaurs, approach snakes in braincase structure. The hypothesis of a sister-group relationship of snakes and mosasauroids is discussed in t he light of how hypotheses of homology, or synapomorphy, can be established on an empirical, i.e. testable and potentially falsifiable basis. The esta blishment of homology qua synapomorphy is recognized as a procedure involvi ng at least two levels of generalization. The most basic level is the conje cture of similarity of constituent elements of two or more organisms. Such conjectures of similarity maintain their testability, and falsifiability, o nly if established by reference to topographical equivalence, or equivalenc e of connectivity. (C) 2000 The Linnean Society of London.