Mechanisms of behavioral evolution
Research in the Hoke lab examines the evolution of developmental and molecular influences on the structure and function of the nervous system, and consequently on behavior. We use an integrative mechanistic approach to address questions of neural and behavioral evolution including the role of developmental plasticity and phenotypic integration in the evolution of behavior, and the extent to which parallel independent evolutionary transitions share common molecular, developmental, and neural substrates. Our research relies on two primary study systems: acoustic social communication in frogs and anti-predator strategies in guppies.
Research in the Hoke lab examines the evolution of developmental and molecular influences on the structure and function of the nervous system, and consequently on behavior. We use an integrative mechanistic approach to address questions of neural and behavioral evolution including the role of developmental plasticity and phenotypic integration in the evolution of behavior, and the extent to which parallel independent evolutionary transitions share common molecular, developmental, and neural substrates. Our research relies on two primary study systems: acoustic social communication in frogs and anti-predator strategies in guppies.
Reproductive Decision Making
We study mechanisms of parallel evolution of mating decisions, integrating comparative development and structure of the ear and central auditory processing centers with ecological factors driving evolution. Our aim is to determine whether similar selective pressures modify common or distinct molecular, developmental, and morphological substrates to detail the interplay between system robustness and pleiotropy in determining evolutionary lability. We’re especially obsessed with the loss and regain of outer and middle ear structures in bufonid toads.
We also study the neural mechanisms of decision-making to understand how modulation of sensorimotor integration generates the subtle context-dependence that matches the behavior to an animal’s needs and its external environment. Vertebrates have conserved neural circuits that mediate this balance of competing demands to select and enact a single behavior. The well-studied neural system underlying the robust behavioral responses to conspecific vocalizations offers a unique opportunity to understand how reproductive state, recent experience, and current environment together shape the sensory-motor relay and thus determine the details of the behavioral response.
We study mechanisms of parallel evolution of mating decisions, integrating comparative development and structure of the ear and central auditory processing centers with ecological factors driving evolution. Our aim is to determine whether similar selective pressures modify common or distinct molecular, developmental, and morphological substrates to detail the interplay between system robustness and pleiotropy in determining evolutionary lability. We’re especially obsessed with the loss and regain of outer and middle ear structures in bufonid toads.
We also study the neural mechanisms of decision-making to understand how modulation of sensorimotor integration generates the subtle context-dependence that matches the behavior to an animal’s needs and its external environment. Vertebrates have conserved neural circuits that mediate this balance of competing demands to select and enact a single behavior. The well-studied neural system underlying the robust behavioral responses to conspecific vocalizations offers a unique opportunity to understand how reproductive state, recent experience, and current environment together shape the sensory-motor relay and thus determine the details of the behavioral response.
Anti-predator strategies
The ability of the Trinidadian guppy (Poecilia reticulata) to rapidly adapt to changing environmental pressures has made it a model system in ecology and evolutionary biology. Much of the adaptive variation observed in guppies is associated with predation pressure. In downstream high-predation localities guppies co-occur with piscivorous fish, which prey intensely on guppies. These major predators are prevented from upstream migration by waterfall barriers, resulting in low-predation localities at higher elevations. Here guppies co-occur only with minor predators. High-predation guppies have repeatedly and independently colonized and adapted to upstream low predation environments, resulting in rapid, parallel changes in life history traits, behavior, and morphology.
Guppies derived from high- and low-predation source populations show robust behavioral differences, even after multiple generations of rearing in a common laboratory environment, and many behaviors also change in response to developmental exposure to predator cues. Our lab is interested in understanding how genetic and environmental forces interact to shape complex phenotypes and their evolution. To address this question, we rear guppies from different source populations with and without chemical cues from predators and examine neuroendocrine, transcriptional, morphological, and physiological correlates of anti-predator behavior. We hope to disentangle genetic and environmental influences on functional neural circuits and behavior to characterize the interplay between developmental and functional constraints, developmental plasticity, and adaptive evolution.
The ability of the Trinidadian guppy (Poecilia reticulata) to rapidly adapt to changing environmental pressures has made it a model system in ecology and evolutionary biology. Much of the adaptive variation observed in guppies is associated with predation pressure. In downstream high-predation localities guppies co-occur with piscivorous fish, which prey intensely on guppies. These major predators are prevented from upstream migration by waterfall barriers, resulting in low-predation localities at higher elevations. Here guppies co-occur only with minor predators. High-predation guppies have repeatedly and independently colonized and adapted to upstream low predation environments, resulting in rapid, parallel changes in life history traits, behavior, and morphology.
Guppies derived from high- and low-predation source populations show robust behavioral differences, even after multiple generations of rearing in a common laboratory environment, and many behaviors also change in response to developmental exposure to predator cues. Our lab is interested in understanding how genetic and environmental forces interact to shape complex phenotypes and their evolution. To address this question, we rear guppies from different source populations with and without chemical cues from predators and examine neuroendocrine, transcriptional, morphological, and physiological correlates of anti-predator behavior. We hope to disentangle genetic and environmental influences on functional neural circuits and behavior to characterize the interplay between developmental and functional constraints, developmental plasticity, and adaptive evolution.