Behavioral Evolutionary Ecology Research in the Smith Lab:
Our research integrates perspectives from evolutionary biology, ecology, animal behavior, and physiology in an effort to understand how natural selection and current ecological conditions shape decision-making in mammalian societies. We test modern theories of evolution using long-term data on free-living mammals to understand the causes and consequences of mammalian social evolution.
Current research questions:
1. Which evolutionary forces shape patterns of cooperation and the emergence of leaders in mammals, including humans? Which traits co-evolve with the emergence of cooperation and leadership in mammalian societies?
2. Which social and endocrine mechanisms permit animals to cope with life in unpredictable environments? Are responses to risk-taking and predator avoidance socially-learned? To what extent do individual and environmental factors shape responses to stressors?
3. What are the costs and benefits of social network connections among mammals? Does network structure predict ectoparasite transmission, and, thus, the potential for disease? Do social ties buffer individuals from ecological stressors, such as predator-induced stress?
Biological systems and collaborations:
We focus on rich data sets for which extensive behavioral, demographic, genetic, and endocrine measures are available for multiple generations of individually-marked populations of free-living, social rodent and carnivores.
Our research integrates perspectives from evolutionary biology, ecology, animal behavior, and physiology in an effort to understand how natural selection and current ecological conditions shape decision-making in mammalian societies. We test modern theories of evolution using long-term data on free-living mammals to understand the causes and consequences of mammalian social evolution.
Current research questions:
1. Which evolutionary forces shape patterns of cooperation and the emergence of leaders in mammals, including humans? Which traits co-evolve with the emergence of cooperation and leadership in mammalian societies?
2. Which social and endocrine mechanisms permit animals to cope with life in unpredictable environments? Are responses to risk-taking and predator avoidance socially-learned? To what extent do individual and environmental factors shape responses to stressors?
3. What are the costs and benefits of social network connections among mammals? Does network structure predict ectoparasite transmission, and, thus, the potential for disease? Do social ties buffer individuals from ecological stressors, such as predator-induced stress?
Biological systems and collaborations:
We focus on rich data sets for which extensive behavioral, demographic, genetic, and endocrine measures are available for multiple generations of individually-marked populations of free-living, social rodent and carnivores.
Our Long-term Study of California Ground Squirrels at Briones Regional Park in the San Francisco Bay Area is supported by the National Science Foundation, the Barrett Foundation, the W. M. Keck Foundation, the Contra Costa Fish and Wildlife Fund, and Mary Bowerman Science and Research Program.
We monitor the life history traits, social behavior, and antipredator behavior of marked individuals. We collect endocrine and genetic samples in an effort to understand the causes and consequences of their cooperation.
Kin-biased social networks:
California ground squirrels are facultatively social mammals that likely foster social networks with family members. These social interactions may be represented over time as dynamic social networks. We expect that California ground squirrels also maintain kin-biased social networks.
Temporal and spatial network dynamics:
We are modeling spatial and temporal dynamics of California ground squirrels using a novel data logger approach to continuously record burrow use. We are elucidating the factors shaping variation in temporal and spatial networks. We are currently seeking funds from the NSF to support a collaboration with Any Sih at UC-Davis on this project.
California ground squirrels are facultatively social mammals that likely foster social networks with family members. These social interactions may be represented over time as dynamic social networks. We expect that California ground squirrels also maintain kin-biased social networks.
Temporal and spatial network dynamics:
We are modeling spatial and temporal dynamics of California ground squirrels using a novel data logger approach to continuously record burrow use. We are elucidating the factors shaping variation in temporal and spatial networks. We are currently seeking funds from the NSF to support a collaboration with Any Sih at UC-Davis on this project.
Disease ecology and transmission networks:
We seek to understand how disease networks in wild mammals. California ground squirrels harbor fleas and ticks, both of which are potential vectors for zoonotic diseases. Disease ecology research is conducted in collaboration with Dr. Robert Lane at UC-Berkeley and the California Department of Public Health.
We seek to understand how disease networks in wild mammals. California ground squirrels harbor fleas and ticks, both of which are potential vectors for zoonotic diseases. Disease ecology research is conducted in collaboration with Dr. Robert Lane at UC-Berkeley and the California Department of Public Health.
Ecology of Fear: Predator-induced vocalizations and stress responses
California ground squirrels possess myriad of adaptations to cope with natural predators with which they have co-evolved. However, little is known about the potential for sublethal effects of predators on these animals or how the acoustical properties of the vocalizations vary across ontogeny.
Our endocrine studies rely upon minimally-invasive sampling in the captive and field conditions. We are finding that predators, including humans, trigger vocalizations and stress responses in these animals.
California ground squirrels possess myriad of adaptations to cope with natural predators with which they have co-evolved. However, little is known about the potential for sublethal effects of predators on these animals or how the acoustical properties of the vocalizations vary across ontogeny.
Our endocrine studies rely upon minimally-invasive sampling in the captive and field conditions. We are finding that predators, including humans, trigger vocalizations and stress responses in these animals.
Our research focusing on the stress response of California ground squirrels is in collaboration with the Lacey Lab at the University of California Berkeley.
We collaborate with Clark Lab at San Diego State University to study physiological responses of squirrels to rattlesnakes. Our field experiments provide novel evidence for the social buffering hypothesis, indicating that conspecific presence buffers predator-induced stress. This finding compliments our work at Briones Regional Park indicating that the social environment is highly predictive of behavioral trade-offs during foraging.
We collaborate with Clark Lab at San Diego State University to study physiological responses of squirrels to rattlesnakes. Our field experiments provide novel evidence for the social buffering hypothesis, indicating that conspecific presence buffers predator-induced stress. This finding compliments our work at Briones Regional Park indicating that the social environment is highly predictive of behavioral trade-offs during foraging.
We collaborate with Dr. Kay E. Holekamp at Michigan State University to study the social behavior of spotted hyenas. Kay initiated her amazing Mara Hyena Project in Kenya back in 1988 and these rich data continue to offer new insights into why social mammals cooperate, maintain social networks and engage in other forms of complex social behaviors. We find that social network dynamics vary over time but connections among kin are highly resilient. Adult females hyenas form powerful coalitions, intervening on behalf of maternal and paternal kin. Adult females lead in collective movements and use greeting rituals to promote cooperation and reduce conflict at reunions within their fluid societies, shaped by fission-fusion dynamics.
In collaboration with Dr. Daniel T. Blumstein at the University of California Los Angeles, we also study the behavior and endocrinology of marked yellow-bellied marmots across their lives in the areas surrounding the Rocky Mountain Biological Laboratory in Colorado. This foundations of this study date back to 1962. We are finding that outcomes during play early in life predict dominance status later in life, that affiliative interactions increase in symmetry as marmots mature, individuals possess consistent endocrine traits, and high-ranking females are less "stressed" and produce more offspring than low-ranking female marmots.
In collaboration with Dr. Daniel T. Blumstein at the University of California Los Angeles, we also study the behavior and endocrinology of marked yellow-bellied marmots across their lives in the areas surrounding the Rocky Mountain Biological Laboratory in Colorado. This foundations of this study date back to 1962. We are finding that outcomes during play early in life predict dominance status later in life, that affiliative interactions increase in symmetry as marmots mature, individuals possess consistent endocrine traits, and high-ranking females are less "stressed" and produce more offspring than low-ranking female marmots.
