Format

Send to

Choose Destination
Nat Commun. 2016 Sep 27;7:12931. doi: 10.1038/ncomms12931.

Bony cranial ornamentation linked to rapid evolution of gigantic theropod dinosaurs.

Author information

1
Department of Biological Sciences, North Carolina State University, Raleigh, North Carolina 27695, USA.
2
Paleontology Research Laboratory, North Carolina Museum of Natural Sciences, Raleigh, North Carolina 27603, USA.
3
Department of Microbiology and Immunology, Montana State University, Bozeman, Montana 59717, USA.
4
Department of Earth Sciences, Montana State University, Bozeman, Montana 59717, USA.

Abstract

Exaggerated cranial structures such as crests and horns, hereafter referred to collectively as ornaments, are pervasive across animal species. These structures perform vital roles in visual communication and physical interactions within and between species. Yet the origin and influence of ornamentation on speciation and ecology across macroevolutionary time scales remains poorly understood for virtually all animals. Here, we explore correlative evolution of osseous cranial ornaments with large body size in theropod dinosaurs using a phylogenetic comparative framework. We find that body size evolved directionally toward phyletic giantism an order of magnitude faster in theropod species possessing ornaments compared with unadorned lineages. In addition, we find a body mass threshold below which bony cranial ornaments do not originate. Maniraptoriform dinosaurs generally lack osseous cranial ornaments despite repeatedly crossing this body size threshold. Our study provides novel, quantitative support for a shift in selective pressures on socio-sexual display mechanisms in theropods coincident with the evolution of pennaceous feathers.

Supplemental Content

Full text links

Icon for Nature Publishing Group Icon for PubMed Central
Loading ...
Support Center