LTREB: Elucidating mechanisms mediating phenotypic responses to rapid urbanization

The rapid expansion of cities increases interactions between humans and many animals. Behavior, physiology, and even body shape within animal populations often change in response to those interactions. This influences the population’s survival and reproductive rates. The trait changes can be inherited as genes underlying beneficial traits are passed down from one generation to the next. Alternatively, an individual may respond within its lifetime, for example by changing how it behaves. This is known as phenotypic plasticity. Such plasticity may help animals or it may just be a pathological effect due to poor nutrition or stress. This work uses a long-term study of spotted hyenas to test hypotheses about the drivers of trait change in response to urbanization. The work measures trait variation among hyenas living in rural, transitional, and urban environments in East Africa. It then tests for a genetic basis of the traits. Finally, this work will explore how these trait changes correspond to hyena health, reproduction and survival. Understanding whether animals respond to urbanization through evolution, phenotypic plasticity or a mixture increases our understanding of the relative force of nature verses nurture in shaping animal responses to humans. Outreach to both the lay public and management stakeholders will ensure that the work will inform management of vulnerable species, and urban planning in similar environments. Additional broader impacts include training students and researchers, outreach to schools, public talks, and contributions to popular press and film documentaries about hyenas and conservation. This proposal exploits a unique opportunity to monitor trait responses to urbanization and identify their causes in a long-term study of wild spotted hyenas (Crocuta crocuta). The work focuses on hyenas living in undisturbed and transitional habitats in Kenya and compares them to hyenas from Ethiopia that have lived in cities for centuries. Human population growth has allowed some hyenas increased access to food including livestock and garbage dumps. Hyenas living close to humans also encounter fewer lions, which compete with and often kill hyenas. This work will identify which hyena traits vary with exposure to urbanization and then estimate trait heritability by partitioning trait variation into additive genetic and environmental (plastic) components. The study will incorporate data from 38 years of prior research and enable assessment of associations between specific traits and fitness to quantify how urbanization affects the magnitude and direction of selection. It will also considering nonadaptive explanations of how urbanization may compromise hyena health using genomic analyses and GPS telemetry to track hyena movement. Biotechnology and artificial intelligence will yield insights into how animals cope or thrive with exposure to urbanization, and changing environments. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria. NSF Award ID: 2617682 | Program: 01002627DB NSF RESEARCH & RELATED ACTIVIT | Principal Investigator: Zachary Laubach | Institution: University of Colorado at Boulder, BOULDER, CO | Award Amount: $599,994 View on NSF Award Search: https://www.nsf.gov/awardsearch/show-award/?AWD_ID=2617682 View on Research.gov: https://www.research.gov/awardapi-service/v1/awards/2617682.html