Biomechanics, morphology, ecology, and stable isotopes
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Sculpture, painting, and photography
I am from the perpetually beautiful, occasionally desolate, and frequently harsh place called Wyoming. I spent much of my early life biking in the prairie, hiking in the mountains, and taking the natural world around me somewhat for granted. Somewhere around middle school, I discovered that dinosaurs were more interesting in real life than they were in picture books, and that steered me toward a career in science.
Carl Sagan wrote that, "Finding out the way the world really works requires a mix of hunches, intuition, and brilliant creativity; it also requires skeptical scrutiny of every step." I like to think of myself as a creative person, and I endeavor to bring that creativity into my study of how animals have adapted to the challenges that their lives present to them. As for the second part of the quote, regarding skeptical scrutiny, I am still in training. I will use this website to document the process.
Flight performance of Turkey Vultures
Isotopic niches of Cinclodes ovenbirds
Ecomorphology of Cinclodes ovenbirds
I am interested in the mechanics, physiology, and ecological consequences of animal movement, and in the interplay between ecology and animal performance. I enjoy projects that draw from multiple disciplines (morphology, biomechanics, stable isotope ecology, etc.), and feel strongly that such multifaceted datasets are powerful tools with which to approach these questions. I have a somewhat wandering focus, but my work has generally centered on form-function relationships and niche evolution in birds.
Most recently, I have been 3-D tracking free-flying turkey vultures (Cathartes aura) across an elevation gradient to investigate how the birds compensate for lower density air at high elevation, and how they respond to variable wind conditions. This work is still progressing, but the early cliff note seems to be that birds flying at high elevation maintain higher airspeeds than their low-elevation counterparts.
I have also studied morphological evolution in a lineage of South American birds called Cinclodes, and showed that despite being physiologically and ecologically diverse, the species of Cinclodes are morphologically quite similar to each other. I also used stable isotope analysis to investigate niche evolution in Cinclodes, and found the species that inhabit broader ranges also consumed more diverse resources. This result provides support for the Resource Breadth Hypothesis, and may be the first application of stable isotope analysis to address a macroecological question.
Bachelor of Science
University of Wyoming
Rader, J. A., P. Sabat, R.T. Chesser, S. D. Newsome and C. Martínez del Rio. Isotopic niches are not conservative. In prep.
Newsome, S. D., P. Sabat, N. Wolf, J. A. Rader, and C. Martínez del Rio. Multi-tissue d2H analysis reveals altitudinal migration and tissue-specific discrimination patterns in Cinclodes. Ecosphere. 2015.
Rader, J. A. and T. L. Hedrick. 2016. Behavioral compensation for decreased air density in turkey vultures. SICB Annual Meeting 2016: Portland, OR.
Rader, J. A., M.E. Dillon and C. Martínez del Rio. 2015. Isotopic niches are not conservative and confirm Brown's resource breadth hypothesis. SICB Annual Meeting 2015: Palm Beach, FL.
Rader, J. A., M. E. Dillon and C. Martínez del Rio. 2014. Delineating ecological niches and their evolution from stable isotopes and museum specimens. SICB Annual Meeting 2014: Austin, TX.
Rader, J. A., S. D. Newsome and C. Martínez del Rio. 2013. Phenotype-environment correlations inCinclodes ovenbirds: Linking morphology to isotopic niche. SICB Annual Meeting 2013: San Francisco, CA.
Rader, J. A., S. D. Newsome and C. Martínez del Rio. 2012. Exploring phenotype-environment correlations in South American Cinclodes ovenbirds Part 1: Characterizing the isotopic niche. NAOC-V 2012: Vancouver, B.C.
Rader, J. A., S. D. Newsome and C. Martínez del Rio. 2012. Of Isotopes and Ovenbirds: Seeking phenotype-environment correlations in South American Cinclodes ovenbirds. SICB Annual Meeting 2012: Charleston, SC.
Rader, J. A. and B. Breithaupt. 2009. An evaluation of methods for estimating the body mass of large animals with reference to Apatosaurus excelsus. Journal of Vertebrate Paleontology: Vol. 29, No. 3 suppl.
Rader, J. A. and B. Breithaupt. 2008. Mass Estimates for Apatosaurus excelsus: A comparison of modeling methods. Undergraduate Research Day 2008, University of Wyoming: Laramie, WY.
In addition to my professional life, I have hobbies. Probably too many of them, if I'm honest. That said, my hobbies make me happy, so I'm not giving them up!
I enjoy a fair amount of time biking on the roads and trails of North Carolina, though I must confess... I miss the mountain bike trails in Wyoming! I especially love the challenge of a long, steep mountain road.
I mentioned earlier that I like to think of myself as being a creative person. I have been running a freelance sculpture business for a while. My goal is to use whatever scientific resources that I can find to reconstruct prehistoric animals with a reasonable amount of accuracy.
I also dabble in painting. I am an absolute rank-amateur, but what the hell, it's fun.
Finally, and when I'm not doing any of the above, you can probably find me turning a wrench on my old Datsun.