MSc Student
Advisors: Patrick Lemell
Unit for Integrative Zoology, Department of Evolutionary Biology, University of Vienna

Abstract

Cranial kinesis refers to distinct intracranial movements other than the jaw joint, middle ear and the hypobranchial skeleton. With respect to tetrapods, investigations on cranial kinesis have been conducted especially in extant Sauropsida (birds, ophidians/snakes, non-ophidian squamates). Different kinds of cranial kinesis have been described for Squamata, including metakinesis, mesokinesis, streptostyly and amphikinesis. Within squamates, geckos are known for their ability of cranial kinesis, thus this clade is of special interest providing a lot of species from less to highly kinetic. Within this current knowledge, the aim of my master thesis is to analyze the feeding mechanisms of the leopard gecko Eublepharis macularius with special emphasis on the functional morphology of the major parts of the feeding apparatus involved in cranial kinesis. Hence, six individuals of Eublepharis macularius were filmed during food consumption on different prey items, using high-speed cinematography. The Feeding Cycle was divided into the capture phase, the oral transport phases and the oral manipulation phases. Each of these gape cycles was then analysed. The angle between the frontal and the parietal bone was measured at specific timepoints of each gape cycle. This angle, occurring at the so called fronto-parietal suture, allows to quantify mesokinetic movements. First results of the kinematic analyses were compared to morphological data gained from 3D visualization of microCT scans and the reconstruction of the muscles in the skull area. Compared to other geckos, the skull of Eublepharis macularius shows more kinetic potential; this may be important for gape and bite force during feeding.

Keywords: Eublepharis macularius, Feeding, Cranial kinesis, Gape cycle, High-speed cinematography, Skull morphology