Author: Kara Reardon

Extensive research on the habitat use of Caribbean anole species has allowed for a general understanding of the ecomorphs and how they partition the habitat of a singular tree. However, less is known about the habitat use of geckos, specifically Phelsuma laticauda, which has adhesive toe pads similar to anoles, but could differ from anoles in toe pad performance due to their unique shape. Travis Hagey from Mississippi University for Women, along with John Philips and Eben Gering (University of Idaho and Michigan State University) examined preferred perch types of Anolis carolinensis (green anole), Norops sagrei (brown anole), and Phelsuma laticauda after placing them in similar habitats in Kauai and Oahu, HI.

They found that texture had the largest effect on habitat use where geckos used smooth surfaces in the canopy and brown anoles used rough surfaces near the ground. This study interestingly created polymer casts of different textured surfaces and used a stylus profiler to quantify miniscule peaks and valleys within terrains. Brown and green anoles partitioned the habitat as expected, while geckos shared the canopy with green anoles, but had a wider range of perch angles because they were able to utilize the bottom of leaves as well.

The gecko is ecologically similar to the crown-giant and morphologically similar to the twig anole, and this study leads to further questions about how geckos would partition their habitats in the presence of anoles. It calls for research further into what genetic variation among these species might affect adaptation, and how geckos balance tradeoffs of toe pad adhesiveness, limb-length, and sprint speed as Caribbean anoles do to maximize fitness and survival.

Have you ever wondered which muscle is the strongest? Depending on a muscle’s function, it can have different levels of performance. Muscle performance can be quantified by measuring several different characteristics, such as time between muscle twitches, contraction velocities, and muscle curvature. Previous work in quantifying these values in jaw and leg muscles in three species of anoles led to questions about what gene functions these different functioning muscles regulate. Andrea Liebl with the University of South Dakota, along with colleagues at the University of Iowa and Brown University, addressed this question. She did this by working to identify candidate genes that may be involved in creating the functional differences seen between jaw muscles involved in biting and leg muscles involved in locomotion.

After using a PCoA Analysis that showed distinct clustering of different gene expression between the two muscles, they were able to find differences in specific genes and their expression in the two muscle types as well. Genes that differed in expression were classified and placed in groups based on function that may play a role in muscle performance. Genes that regulate energy for the cell such as those involved in ATP synthesis and mitochondria were found to differ in expression in the jaw and leg muscles, as well as genes involved in muscle structure, contraction, and activity. These findings allow for further work that is currently being done to address differences in gene expression among four species of anoles. This study along with further work gives great insight into what differences in muscle physiology leads to specific muscle performance as well as whole organism performance.