Collaborative Research: Mesozoic Tethyan paleocommunity dynamics: Modelling complexity and stablity during times of biotic escalation and community restructuring<br/><br/>The Mesozoic Era began in the aftermath of Earth's largest mass extinction 251 million years ago, ending 66 million years ago with another mass extinction. The current project focuses on ecosystems of an ancient ocean which covered much of western Europe during the Mesozoic and left behind a rich, well-documented fossil record. The groundwork for modern oceans was laid during this time with increasingly complex ecosystems. The relationship between the complexity and stability of ecosystems is, however, poorly understood. The project will examine that relationship by modeling the complex dynamics of Mesozoic marine ecosystems using food webs, which capture the interactions and energy transfer between species in biological communities. Food web reactions to environmental disturbances are informative of ecosystem resilience. Analyzing ancient food webs will be accomplished with a suite of mathematical and computational models. <br/><br/>Ecosystem responses to changes in biological complexity and environmental disturbance remain poorly understood. Anthropogenically-driven global biological change is currently resulting in catastrophic losses of biodiversity. To anticipate ecosystem responses and effectively manage resources, we must understand how ecosystems respond to extreme changes; yet there are no precedents in human experience to guide us. The fossil record documents extreme ecosystem changes and this project will provide analogs from the past to enable better forecasts for modern marine ecosystems. This information will be distributed to the public, educators and students through a variety of programs at the California Academy of Sciences.