Do all frogs swim alike? (Archive)

Originally posted March 11, 2018.

Itzue W. Caviedes-Solis is graduate student biology who studies tree frogs. Tree frogs move in their environments by jumping, swimming and climbing. Her research aims to understand how Mexican tree frogs move while they swim, how fast they go, and how are those influenced by how they look and where they live.

Why and how do species live where they do? It’s a question that biologists have been asking from centuries. Tree frogs are elusive and majestic animals that inhabit forest all around the world. The larger diversity of tree frogs in America is distributed close to the tropics, a place with warmer temperatures and a huge variety of microhabitats. Tree frogs move in their environments by jumping, swimming and climbing. The performance and efficiency of each movement is related to their evolutionary history (their ancestry), the environment where they live and morphology (how they look). For example, tree frogs have distinctive large discs in their fingers that allow them to hold on to vertical surfaces and climb to the top of the trees in the forest. Even though tree frogs spend most of their time… well… up in the trees, they reproduce in the water. Therefore, being good swimmers is crucial! It provides tree frogs an advantage during reproductive season and during earlier life stages after metamorphosis. Previous research suggests that swimming has low variation among frog families across the globe. However, I found a high rate of variation in swimming behaviors among Mexican tree frogs, and those behaviors result in different speeds! For example, species can have simultaneous or alternated backstroke, rowing present or absent, and when absent they keep the arms in different positions. Finally, behavior and speed are also influenced by where the frogs are living, is not the same swimming in a fast flow river against the flow… than swimming in a quiet still pond. My research aims to disentangle all those factors! To understand how tree frogs move while they swim, how fast they go, and how are those influenced by how they looked and where they live. In addition, like every good evolutionary biologist, I approach all those questions considering their evolutionary history along millions of years!