2.12.2009

Lizard Legs


Some of you know and others are now finding out that this semester I am "working" in a lab where we race lizards.  My beloved father has been bugging me about putting up proof of my reptilian exploits, so here it is :)  
I work with Dr. Eric McElroy.  It is his first year as a professor at the college, so much of this semester has been spent setting up the racetrack for the lizards and also setting up all of the computers we use for the analysis of our data.  Kristen, another honors student doing her independent study in the lab, is in charge of the kinematics.  So she analyzes the high speed video we collect of the trials.  In a couple of the pictures, you can see the white dots we use to collect data on specific limb and spine movements.  The videos are of vertical and horizontal views, and a calibration cube made of legos is used to input the video data into a program so we can analyze it in 3D.   My main focus is the study of the forces the lizard outputs when it runs down the track.  A force plate is embedded in the track and each time the lizard runs, 5 seconds of data is collected.  Then, I use another program to filter out the "noise," like the forces exerted from the building shaking and air particles vibrating (which all do at about 60 Hz I believe).  Then, another program breaks up the forces into vertical, medio-lateral, and fore-aft.  Those are the forces down on the plate, the forces to the right or left, and the forces forward and backward.  I analyze the output graphs based on footfalls on the force-plate, and that information is used to find how the lizard pushes on its limbs to propel itself along the track.  Right now we are focusing on acceleration, so right when the lizard starts running.  But later in the semester we might move onto terminal, or peak, velocity.  The species we have right now are Agamas, Fire Skinks, and tachydermis (the really little ones with super long tails that remind me of the tiny dinosaurs that attack that one guy in Jurassic park).  I am really enjoying the work in the lab so far and look forward to the rest of the semester!

2 comments:

Hilary Surratt said...

That looks so fun! This is very interesting, I had no idea that people actually cared about the lizards and how they run! It looks like here that the lizards are spoiled by you! :)

Anonymous said...

Leapin' Lizards!!!! That is a wonderful post. Keep the reptilian news coming.