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Showing posts from 2014

Dissection of the hindlimb of monitor lizards: V. varius and V. komodoensis, Part 1 of 4, Superficial Dorsal aspect.

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One of the major questions I am trying to determine in my research is how muscle and bone strains change with body size and habitat among Australia’s giant lizards the Varanids (aka monitor lizards aka goannas aka large uncooperative lizards). When I first attempted to dissect the hindlimb muscle of monitor lizards I was amazed about how little information there was on the topic. In the end the two most helpful bits of literature was the Snyder paper from 1954, and the book chapter, The Appendicular locomotor apparatus of Lepidosaurs, by Russell and Bauer, (2008), in Biology of the Reptilia, Vol 21.  Luckily I had a visit from muscle expert Taylor Dick, from Simon Fraser University Canada, and we were able to dissect some big lizards.  As a guide to help anyone else who might also be silly enough to want to follow along this line of inquiry we have made a guide below to help you identify some of the major muscles in the lizard hindlimb.  There will be 4 posts in total, th

Evolution of bipedal running

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Awesome lizard shot by Simon Pynt  which sadly the journal did not want on its cover  This week my paper on the evolution of bipedalism came out in the journal Evolution. This work is part of a long ongoing project understanding why these lizards sometimes run on two legs and sometimes run on four, and why Australian agamid lizards in particular seem to be so very good at the former. But to understand this we need a little bit of background into Bipedalism and why lizards are so weird. Awesome picture of a dinosaur I stole from the web. To make this blog post look cooler.     Bipedalism (running on two legs) evolved independently many times, for example in hopping marsupials (like kangaroos), hopping placentals (like kangaroo rats), primates (like us), birds, dinosaurs, lizards, insects, and this awesome octopus ! In birds, primates and dinosaurs the forelimbs appear to be used for something else so bipedalism makes sense, and hopping on two legs can save energy

Notes on running large lizards over forceplates

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Taylor Dick, SFU (probably didn't expect to be holding a lizard that big anytime  during her stay). Anyone who has had the misfortune of stumbling upon this blog, and particularly those who have suffered through many of its posts might have noticed that one of the main themes is determining how muscle and bone strains change with body size and habitat among Australia’s giant lizards the Varanids (aka monitor lizards aka goannas aka large uncooperative lizards). Recently I had convinced Muscle expert Taylor Dick from SFU to come to Australia to study these questions with the eventual goal of building a musculoskeletal model of these lizards in the open-source biomechanics software OpenSim. She had already endured one trip out to the Australian desert in order to catch these beasts , but more was yet to come.   Example output of the force plate from a dragon lizard, A. gilberti Force plate design, shown here without a plate on the top. Photo probably taken during

How to catch a giant varanid lizard

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Recently at the SEB conference in Spain I convinced a muscle expert, Taylor Dick from Simon Fraser University in Canada, to come out to Australia to study muscle variation in Australian varanids. The purpose of this study was based upon a previous paper I had written “Lizard Tricks” of which I wrote a blog about here . But incase you missed it, basically I had found that differences in the Kinematics of the lizards hindlimb were not based upon changes in lizard size (as I had expected) but rather were related to changes in the lizards habitat. The Arboreal lizards (both big and small) had a crouched, sprawling posture, as if they were in a perpetual pushup, the terrestrial lizards (again both big and small) had a more upright posture. The reason for this difference was probably since arboreal lizards wanted to be close to the surface they were climbing on to avoid toppling over (and so had the crouched posture), while the terrestrial lizards wanted to improve stride length, and so

Making nice figures

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Figures are Important http://www.nature.com/nature/journal/vaop/ncurrent/full/nature12871.html Everyone seems to know that figures are the most important part of the paper, so why not do a little research into not only what makes a great figure, but also what makes a unique memorable figure.  Before you write a paper, or even start a project, its a good idea to know what figures you want to make. There are many different ways to display data, so have a look through them and decide which ones might be suitable for you.  These are some websites I like to take inspiration from  https://github.com/mbostock/d3/wiki/Gallery http://nicefigure.tumblr.com/ http://www.plosone.org/article/info:doi/10.1371/journal.pone.0007783 One important part of making figures is the use of color. Most journals will let you publish online color figures, but these must also be view-able in black and white (greyscale) format. It is therefore important to vary shading in your figure between su