research fellow and lecturer - university of … thomas nelson, "allometry in kangaroos"....
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Honours projects in Genetics and Evolution with Marc Jones ARC DECRA Research Fellow and Lecturer The University of Adelaide [email protected] http://www.adelaide.edu.au/directory/marc.jones https://biological.adelaide.edu.au/current‐students/honours/genetics/ My research interests encompass the evolution of reptiles and amphibians but currently focus on the following areas:
‐ bite force in lizards and snakes ‐ skull shape, growth, and structure in lizards and snakes ‐ sea turtle skull shape and growth ‐ evaluating fossil calibrations important to tuatara and lizards
I have a number of active collaborations that are both international and multidisciplinary and I regularly use three innovative approaches:
‐ Generation computer models of anatomical structure using data from X‐ray Computed Tomography
‐ Landmark analysis to quantify the shape of anatomical structures and thus phenotype ‐ Bite force analysis to measure performance (again phenotype)
Ongoing current honours projects: 2015: Ray Chatterji, "Osteology of sea turtles". 2015: Thomas Nelson, "Allometry in Kangaroos". Co supervised with Roger Seymour (University of Adelaide). Completed Honours students: 2014: Jaimi A. Gray, "Agamid lizard skeleton identification and inferences for Pleistocene distributions". Co‐supervised with Mark Hutchinson (South Australia Museum).
A word cloud generated from some of my recent publications
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1. Muscle anatomy in agamid lizards The purpose of the research is to survey variation in jaw muscle anatomy amongst agamid lizards and the extent of the changes related to growth. During the project the student will build a three dimensional computer model of the jaw muscle arrangement in the bearded dragon lizard using X‐ray Computed Tomographic data of a juvenile and adult head stained with Lugo’s iodine solution I2KI (see attached). The computer model will facilitate comparisons with other lizards to better understand evolutionary relationships and jaw function. It may in future also form the basis of a biomechanical analysis to test how the mechanics of the skull responds to specified loading conditions. The student will receive training and first‐hand experience of working with CT scan data and using cutting edge software (Avizo). Both skills have widespread application and will increase the student’s opportunities for future employment and research.
Anticipated activities:
Surveying the literature
Dissection of museum specimens
Segmentation of X‐ray CT scans
Likely joint supervisors
Mark Hutchinson The South Australian Museum
Key Reference:
Jones MEH, Werneburg I, Curtis N, Penrose R, O’Higgins P, Fagan MJ, Evans SE. 2012. The head and neck anatomy of sea turtles (Cryptodira: Chelonioidea) and skull shape in Testudines. PLoS ONE 7(11): e47852
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One slice through the back of the head showing the braincase and muscle chambers as stained by Lugol’s iodine solution
User interface for the C T processing software Avizo
skull roof
lower jaw
temporal bone
brain
external jaw muscle
internal jaw muscle
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2. Skull shape growth in agamid lizards This project would examine some of the dramatic growth changes in agamid lizards. Several key taxa will be chosen an analysed by landmarking computer models generated using CT scans to examine whether there is a common growth pattern and evaluating the implications for function at different growth stages, phylogenetic relationships, and evolutionary process.
Anticipated activities:
Surveying the literature
Geometric Morphometrics using GeoMorph and R
Dissection of museum specimens
Segmentation of X‐ray CT scans
Likely joint supervisors
Mark Hutchinson The South Australian Museum Alessandro Palci The South Australian Museum
Key Reference:
Jones MEH, Werneburg I, Curtis N, Penrose R, O’Higgins P, Fagan MJ, Evans SE. 2012. The head and neck anatomy of sea turtles (Cryptodira: Chelonioidea) and skull shape in Testudines. PLoS ONE 7(11): e47852
A comparison between the skull of a juvenile (~10 mm) and adult water dragon (~60 mm).
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3. Bite force in lizards The purpose of this project is to survey bite force in lizards to establish the relationship between bite force performance and head shape. Target taxa would either include agamid lizards or blue tongue skinks.
Anticipated activities:
Surveying the literature
Supporting the collection of bite force data
Processing of bite force data
Likely joint supervisors
Mark Hutchinson The South Australian Museum
Key references:
Lappin AKL, Jones MEH. 2014. Reliable quantification of bite‐force performance requires use of appropriate biting substrate and standardization of bite out‐lever. Journal of Experimental Biology 217: 4304‐4312.
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4. Bite force and fang shape in snakes The purpose of this project is to survey bite force, fang structure, and skull shape amongst Australian elapid snakes but particularly Tiger snakes, Brown snakes, and Black snakes. This project (or projects as it could be sub‐divded) is part of a wider project examining geographic variation in tiger snakes.
Anticipated activities:
Surveying the literature
Segmentation of X‐ray CT scans
Geometric Morphometrics using GeoMorph and R
Supporting the collection of bite force data
Processing of bite force data
Snake fang impact analysis
Likely joint supervisors
Mark Hutchinson The South Australian Museum Alistair Evans Monash University Vicki Thomson The University of Adelaide
Key references:
Freeman PW, Lemen CA 2007. The trade‐off between tooth strength and tooth penetration: predicting optimal shape of canine teeth. Journal of Zoology 273: 273–280
Jones D, Evans AR, Siu KKW, Rayfield EJ, Donoghue PCJ. 2012. The sharpest tools in the box? Quantitative analysis of conodont element functional morphology. Proc. R. Soc. B 2012 279, 2849‐2854
Lappin AKL, Jones MEH. 2014. Reliable quantification of bite‐force performance requires use of appropriate biting substrate and standardization of bite out‐lever. Journal of Experimental Biology 217: 4304‐4312.