Date of Award


Document Type


Degree Name

Doctor of Philosophy (PhD)


Biological Sciences

Committee Chair/Advisor

Dr. Richard Blob

Committee Member

Dr. Samantha Price

Committee Member

Dr. Kara Powder

Committee Member

Dr. Henry Astley


Many organisms must contend with navigating their environments from birth. An organism could be classified as – and is often studied – in the context of locomotion through a single habitat type. However, many organisms must contend with a wide variety of environmental obstacles and substrates. What’s more, a large group of animals, Lissamphibia, do so while undergoing drastic transformation of their morphology and locomotor appendages. This transformation, term metamorphosis, typically coincides with a movement from water as a tadpole, to land as a frog or salamander. Many studies have associated this transitionary period with decreased locomotor performance and worse survival compared to amphibians pre or post metamorphosis and have termed this paradigm as the “Adaptive Peaks Hypothesis”. This body of work sought to address the generality of the Adaptive Peaks Hypothesis by studying the locomotor performance, development, and survival of a fully aquatic frog, Xenopus laevis. Swimming performance and survival of frogs across developmental stages were measured using high speed cameras and a predation tank where morphological traits were compared between (non)survivors post predation. Another subset of frogs, including aquatic X. laevis and more terrestrial L catesbianus, were used to quantify bone mineral density and material properties of developing frogs. Finally, the aquatic frog, Xenopus laevis, underwent jumping performance trials using high speed cameras and force plates to determine how well an aquatic frog could perform out of the water. The adaptive peaks hypothesis is not as robust as once thought. Xenopus laevis did not experience a performance decrease during metamorphosis, despite similar capture rates from the predators. Furthermore, the bone development of the femur differed from the more terrestrial frogs such that the less dense bones had greater stiffness in Xenopus. Finally, despite being fully aquatic, Xenopus frogs were still capable jumpers across two incline treatments with greater variability in jump performance in the more juvenile stages. Taken together, this body of work builds upon our understanding of animal locomotion by addressing how animals with complex life cycles navigate complex habitats.

Author ORCID Identifier




To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.