Abstract
Cranial ornamentation is widespread throughout the extinct non-avialian Ornithodira, being present throughout Pterosauria, Ornithischia and Saurischia. Ornaments take many forms, and can be composed of at least a dozen different skull bones, indicating multiple origins. Many of these crests serve no clear survival function and it has been suggested that their primary use was for species recognition or sexual display. The distribution within Ornithodira and the form and position of these crests suggest sexual selection as a key factor, although the role of the latter has often been rejected on the grounds of an apparent lack of sexual dimorphism in many species. Surprisingly, the phenomenon of mutual sexual selection -where both males and females are ornamented and both select mates -has been ignored in research on fossil ornithodirans, despite a rich history of research and frequent expression in modern birds. Here, we review the available evidence for the functions of ornithodiran cranial crests and conclude that mutual sexual selection presents a valid hypothesis for their presence and distribution. The integration of mutual sexual selection into future studies is critical to our understanding of ornithodiran ecology, evolution and particularly questions regarding sexual dimorphism.
Original language | English |
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Pages (from-to) | 139-156 |
Number of pages | 18 |
Journal | Lethaia |
Volume | 45 |
Issue number | 2 |
Early online date | 19 Dec 2011 |
DOIs | |
Publication status | Published - Apr 2012 |
Keywords
- Behaviour
- Dinosauria
- ornaments
- Pterosauria
- sexual selection
- THEROPOD DINOSAURS
- MATE CHOICE
- SPECIES RECOGNITION
- BIZARRE STRUCTURES
- RELATIVE GROWTH
- CRANIAL ANATOMY
- ORNITHISCHIA
- ORNAMENTATION
- BEHAVIOR
- CHINA