Terry Dial

Field: Biology, Environment and Society
Areas of Focus: Anatomy, Biology, Birds, Evolution, Fish, Physiology, Wildlife Biology

Expertise

• anatomy and physiology
• comparative vertebrate morphology
• developmental biology
• evolutionary biology
• life history biology
• biomechanics
• fluid dynamics
• fishes and birds

Bio

Terry Dial is a Comparative Anatomist interested in how organisms are put together and how they work. He uses fish and birds to ask questions about tradeoffs associated with growth/development and organismal performance. Questions like: if an animal is growing very quickly does it experience decreased locomotor function during development, or how does increased parental investment lead to more mature and competitive offspring? In order to address these questions, Dial collects data that quantifies organismal performance, using high speed cameras, flow visualization equipment, electromyography, force plates and other methods of quantifying function. Dial also collects data on organismal form – though traditional histological techniques, gross anatomical dissections or using computed tomography (CT; a fancy 3D x-ray device). He then takes advantage of natural variation in life histories (growth rates, parental investment strategies) and compare the form and function of species or populations that differ in some fundamental life history strategy.

Dial's main model system is the Trinidadian guppy, which is a live-bearing fish inhabiting the freshwater streams in Trinidad’s Northern Range mountains. This species of fish invaded this stream network at the end of the most recent ice age and has adapted to environments of differing predation levels. In the main river stems, guppies are exposed to high levels of predation pressure from other fish, birds and invertebrates (high predation = HP). But, high in the headwaters of each tributary, guppies live without these predatory influences and thus have adapted to a whole new environment (low predation = LP). As one can imagine, in the absence of predation, the main selective pressure driving population size are the available resources, which in the LP environments lead to heavy competition among conspecifics. These differential selective pressures – high predation in HP vs. high competition in LP – have resulted in the evolution of contrasting life history traits among guppy populations. HP guppies life fast and die young – they produce lots of offspring, reproduce early in life and grow relatively quickly, whereas the LP guppies produce fewer but larger offspring, reproduce later in life and grow more slowly. It is the contrast in life history strategies between HP and LP populations he finds most interesting!

Dial works physically at the Moab campus, but is available over Zoom and often makes trips to the main campus and other Statewide campuses throughout the year. Fish on!