Research Summary

We are broadly interested in how global events, environmental change, and ecological interactions affect long-term evolution (macroevolution) and ecological communities (macroecology). We combine the fossil record and living biodiversity into a database of natural experiments and mine it for repeated patterns of diversification, extinction, morphological evolution, and ecosystem change to reveal common evolutionary processes. We apply quantitative, phylogenetic and descriptive methods, using approaches from fields as diverse as mathematical simulation, systematics, evolutionary development, community ecology and biomechanics.

Primary Study Groups

Ray-finned fishes (Actinopterygii; e.g. salmon, tuna and their relatives): This group represents the majority of vertebrate species in the modern world (>34,000 species). Ray-fins have dominated aquatic ecosystems since the mid-Paleozoic, come in myriad functional forms, and are widely used in evolutionary and ecological research. They also have an excellent fossil record, containing thousands of complete specimens and preserving traits from which function and ecology can be inferred.

Early Vertebrates: This group represents more than half of the total evolutionary history of vertebrates. Modern vertebrate biodiversity began in the Paleozoic (541-251 million years ago), an interval containing both the origins of major living groups (e.g., ray-finned fishes, tetrapods) and major events in their evolutionary history (e.g., the end-Devonian mass extinction and the subsequent diversification of survivors, 359 million years ago).

Marine Ecosystems: Vertebrates and invertebrates do not exist in vacuum, either in modern reefs or in the past. Ecological interactions, such as predation and competition, between these groups in the first half of their evolutionary history is likely to have affected the course of evolution, both of the lineages themselves and ecosystem structures, leaving a significant imprint on later biodiversity. While observation of modern ecosystems are limited to a snapshot of time, fossil ecosystems preserve and average thousands or millions of years of cascading interactions and environmental change, giving a window to longer-term consequences.