Université de Fribourg

Feeding biomechanics suggests progressive correlation of skull architecture and neck evolution in turtles

Ferreira, Gabriel S. ; Lautenschlager, Stephan ; Evers, Serjoscha W. ; Pfaff, Cathrin ; Kriwet, Jürgen ; Raselli, Irena ; Werneburg, Ingmar

In: Scientific Reports, 2020, vol. 10, p. 5505

The origin of turtles is one of the most long-lasting debates in evolutionary research. During their evolution, a series of modifications changed their relatively kinetic and anapsid skull into an elongated akinetic structure with a unique pulley system redirecting jaw adductor musculature. These modifications were thought to be strongly correlated to functional adaptations, especially to bite...

Université de Fribourg

Evolution of neck vertebral shape and neck retraction at the transition to modern turtles: an integrated geometric morphometric approach

Werneburg, Ingmar ; Wilson, Laura A.B. ; Parr, William C. H. ; Joyce, Walter G.

In: Systematic Biology, 2014, p. syu072

The unique ability of modern turtles to retract their head and neck into the shell through a side-necked (pleurodiran) or hidden-necked (cryptodiran) motion is thought to have evolved independently in crown turtles. The anatomical changes that led to the vertebral shapes of modern turtles, however, are still poorly understood. Here we present comprehensive geometric morphometric analyses that...

Université de Fribourg

Modeling neck mobility in fossil turtles

Werneburg, Ingmar ; Hinz, Juliane K. ; Gumpenberger, Michaela ; Volpato, Virginie ; Natchev, Nikolay ; Joyce, Walter G.

In: Journal of Experimental Zoology Part B: Molecular and Developmental Evolution, 2014, p. -

Turtles have the unparalleled ability to retract their heads and necks within their shell but little is known about the evolution of this trait. Extensive analysis of neck mobility in turtles using radiographs, CT scans, and morphometry reveals that basal turtles possessed less mobility in the neck relative to their extant relatives, although the anatomical prerequisites for modern mobility were...

Université de Fribourg

The hooked element in the pes of turtles (Testudines): a global approach to exploring primary and secondary homology

Joyce, Walter G. ; Werneburg, Ingmar ; Lyson, Tyler R.

In: Journal of Anatomy, 2013, vol. 223, no. 5, p. 421–441

The hooked element in the pes of turtles was historically identified by most palaeontologists and embryologists as a modified fifth metatarsal, and often used as evidence to unite turtles with other reptiles with a hooked element. Some recent embryological studies, however, revealed that this element might represent an enlarged fifth distal tarsal. We herein provide extensive new myological and...