HERRERA‐FLORES, J.A., STUBBS, T.L., BENTON, M.J. 2017. Macroevolutionary patterns in Rhynchocephalia: is the tuatara (Sphenodon punctatus) a living fossil?. Palaeontology, 60, 3, 319-328. DOI: 10.1111/pala.12284
Jorge A. Herrera‐Flores, Thomas L. Stubbs, and Michael J. Benton- Jorge A. Herrera‐Flores - School of Earth Sciences University of Bristol Bristol UK (Email: jorge.herreraflores@bristol.ac.uk)
- Thomas L. Stubbs - School of Earth Sciences University of Bristol Bristol UK (Email: tom.stubbs@bristol.ac.uk)
- Michael J. Benton - School of Earth Sciences University of Bristol Bristol UK (Email: mike.benton@bristol.ac.uk)
- Issue published online: 26 April 2017
- Manuscript Accepted: 19 January 2017
- Manuscript Received: 04 July 2016
The tuatara, Sphenodon punctatus, known from 32 small islands around New Zealand, has often been noted as a classic ‘living fossil’ because of its apparently close resemblance to its Mesozoic forebears and because of a long, low‐diversity history. This designation has been disputed because of the wide diversity of Mesozoic forms and because of derived adaptations in living Sphenodon. We provide a testable definition for ‘living fossils’ based on a slow rate of lineage evolution and a morphology close to the centroid of clade morphospace. We show that through their history since the Triassic, rhynchocephalians had heterogeneous rates of morphological evolution and occupied wide morphospaces during the Triassic and Jurassic, and these then declined in the Cretaceous. In particular, we demonstrate that the extant tuatara underwent unusually slow lineage evolution, and is morphologically conservative, being located near the centre of the morphospace for all Rhynchocephalia.
Data for this study are available in the Dryad Digital Repository https://doi.org/10.5061/dryad.568jh Wiley Online Library (Open Access)