Roland Sookias


I am a researcher with a primary research interest in evolutionary biology, with a focus on the evolution of archosaurs (the group of animals including birds, crocodiles, and dinosaurs). My wider research interests include morphological evolution in general, language and cultural evolution, and sustainable development.

I am currently a Humboldt Stifting postdoc in the Müller lab. I am investigating how better to infer phylogeny in fossil animals using morphological characters, based on comparisons of molecular and morphological phylogenies for modern animals. My initial focus is on archosaurs.

I previously completed a PhD under Richard Butler reassessing the monophyly, anatomy and distribution of the early archosauromorph group Euparkeriidae. I have an MSc from Imperial College London and Uppsala University, and originally studied Zoology at the University of Cambridge.

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Below is a list of my publications, and click here for my own website where you can download all of my work:

Foth C, Ezcurra MD, Sookias RB, Brusatte SL, Butler RJ. 2016. Unappreciated diversification of stem archosaurs during the Middle Triassic predated the dominance of dinosaurs. BMC Evolutionary Biology. Open access.

Sobral G, Sookias RB, Bhullar B-AS, Smith R, Butler RJ, Müller J. 2016. New information on the braincase and inner ear of Euparkeria capensis Broom: implications for diapsid and archosaur evolution. Royal Society Open Science. Open access.

Sookias RB. 2016. The relationships of the Euparkeriidae and the rise of Archosauria. Royal Society Open Science. Open access.

Sookias RB, Sullivan, C., Liu, J. & Butler, R. J. 2014. Systematics of putative euparkeriids (Diapsida: Archosauriformes) from the Triassic of China. PeerJ. Open access.

Sookias RB, Böhmer C, Clack JA. 2014. Redescription and phylogenetic analysis of an enigmatic Pennsylvanian (Late Carboniferous) tetrapod from Nova Scotia, and the lability of Meckelian jaw ossification. PLoS ONE. Open access.

Sookias RB, Sennikov AG, Gower, DJ, Butler RJ. 2014. The monophyly of Euparkeriidae (Reptilia: Archosauriformes) and the origins of crown Archosauria: a revision of Dorosuchus neoetus from the Middle Triassic of Russia. Palaeontology. Main text (pdf).

Butler RJ, Sullivan C, Ezcurra MD, Liu J, Lecuona A, Sookias RB. 2014. New clade of enigmatic early archosaurs yields insights into early pseudosuchian phylogeny and the biogeography of the archosaur radiation. BMC Evolutionary Biology 14:128. Open access.

Sookias RB, Budd GE, Kear BP. 2013. Mesozoic fossil sustainability: synoptic case studies of resource management. GFF 135:131-143. Main text (pdf), Supplement (xls).

Sookias RB, Butler RJ. 2013. Euparkeriidae. In: Anatomy, Phylogeny and Palaeobiology of Early Archosaurs and their Kin, Nesbitt, S. J., Desojo, J. B. & Irmis, R. B. (eds). Geological Society, London, Special Publications 379:35-48. Main text (pdf).

Sookias RB, Benson RBJ, Butler RJ. 2012. Biology, not environment, drives major patterns in maximum tetrapod body size through time. Biology Letters 8:674-677. Main text (pdf), Supplement 1 (doc), Supplement 2 (xls).

Sookias RB, Butler RJ, Benson RBJ. 2012 Rise of dinosaurs reveals major body size transitions are driven by passive processes of trait evolution. Proceedings of the Royal Society B 279:2180-2187. Main text (pdf), Supplement 1 (pdf), Supplement 2 (xls).