The gist
From winter 2021 to fall 2022, I worked with a couple of other undergraduates with the help of our mentor, Dr. Chris Law, to research the evolution of different skeletal structures within the squirrel family, Sciuridae. There are three distinct ecotypes of squirrels--flying, ground, and tree--that have different locomotions and habitats. Using this model system, we asked two main questions:
Q1) How does overall body shape differ between ecotypes?
To answer this, we are quantifying squirrels' body shape using skeletal specimens in natural history museums to see whether the ecotypes' different lifestyles are reflected in their body shape. Read the whole article: Linden TJ, Burtner AE, Rickman J, McFeely A, Santana SE, & Law CJ. 2023. Scaling patterns of body plans differ among squirrel ecotypes. 2023. PeerJ, 11:e14800. https://doi.org/10.7717/peerj.14800. Q2) How do internal structure and external shape differ between ecotypes' limb bones? To answer the internal structure aspect of this question, we used the SegmentGeometry module in 3D Slicer to analyze 3D data from CT scans of squirrel limbs to determine whether the ecotypes have evolved different bone compactness and cross sectional shape, among other metrics. To answer the external shape aspect of this question, we used the Alpaca module in SlicerMorph (3D Slicer) to conduct geometric shape analyzes on the same 3D data limb data. The goal to determine whether the ecotypes have evolved different 3D limb shapes to facilitate their locomotions. Read the whole article: Burtner AE, Rickman J, Linden TJ, Santana SE, & Law CJ. Accepted. Size and locomotor ecology have differing effects on the external and internal morphologies of squirrel (Rodentia: Sciuridae) limb bones. 2023. Integrative Organismal Biology, https://doi.org/10.1093/iob/obad017. |
What I've learned
I've learned everything from collecting data to coding in R to presenting results, which I discuss a bit in my experiential learning reflection. Team Squirrel has presented some of these projects at the UW Undergraduate Research Symposium in May 2021 and May 2022, at the American Society of Mammalogists Annual Meeting in June 2021, and at the Society for Integrative and Comparative Biology Meeting in January 2022 thanks to the support of our amazing mentor, Chris, and the Santana Lab at UW Biology. I had the opportunity to work on this project over the summer of 2021 with the American Museum of Natural History's NSF-funded REU program. I loved this project for the opportunity to learn about evolution and functional morphology and how research generally works!