Morphology and locomotion in terrestrializing gobies
Elizabeth Surovic
The first vertebrate transition from water to land began approximately 380 million years ago and represents one of the most intensively studied major habitat transitions in evolutionary history. This transition required substantial anatomical and physiological changes, including shifts in eye position, the transformation of fins into more robust weight-bearing appendages, changes in body cross-sectional shape, and modifications to head morphology. Although fossils provide important evidence of skeletal change, they reveal far less about the behaviour, ecology, and locomotion of transitional species. Modern analogues can therefore provide more nuanced insights into how morphology and locomotory behaviour interact during terrestrial transitions. Gobies are especially valuable modern analogues because they exhibit a wide range of aquatic, amphibious, and terrestrial locomotory lifestyles. Some species use a form of terrestrial locomotion known as crutching, which may resemble aspects of the locomotion used by early vertebrates moving onto land. This study used species from the family Gobiidae to examine how locomotory lifestyle is associated with morphological evolution across the water-to-land transition. The study addressed five questions: 1) how visual, body-shape, and locomotory traits are associated with lifestyle; 2) whether species with similar lifestyles have converged morphologically; 3) whether these lifestyles have evolved independently multiple times; 4) what functional constraints and trade-offs occur among morphological traits; and 5) whether body shape follows identifiable evolutionary trajectories through time. This talk presents the findings of these analyses, highlights the importance of locomotory diversity in understanding the water-to-land transition, and identifies key questions that remain unresolved.
Meet our speaker:
Liz is a third-year PhD candidate in the Evolution and Ecology Research Centre at UNSW’s School of Biological, Earth and Environmental Sciences. Her research examines how locomotory lifestyles influence morphological evolution during the transition from water to land, using fishes from the families Blenniidae and Gobiidae as modern analogues. For her master’s thesis, Liz investigated the spatial distributions of several snake species in the genus Chironius and conducted fieldwork in the Bolivian Amazon. During her undergraduate studies at Texas A&M University, she analysed remotely operated vehicle footage to help document marine life on the seafloor of the Gulf of Mexico and the Caribbean. She also conducted research in the Stored Ion and Bio-Optics Research Laboratory, where she worked on optimising surface plasmon resonance techniques. Liz has undertaken fieldwork in the Bolivian Amazon and on the island of Guam. Her research has been published in journals spanning applied optics, herpetology, and evolutionary ecology, including Functional Ecology.
