CONTEMPORANEOUS CHANGES IN TERRESTRIAL AND MARINE FUNCTIONAL ECOLOGY DURING ANCIENT AND MODERN MASS EXTINCTION EVENTS: AN ECOSPACE CUBE APPROACH

Biotic crises in Earth’s geologic past offer insight into how environmental perturbations affect the composition of functional guilds within ecosystems. Tiering-motility-feeding ecospace occupation analyses (Bambach et al., 2007; Bush et al., 2007) have successfully been used to characterize marine functional ecology, but similar methods have not yet been developed for terrestrial ecosystems. The lack of terrestrial ecospace analyses inhibits comparisons of functional ecology between the marine and terrestrial realms across mass extinction boundaries. Here, we will present the first tiering-motility-feeding ecospace cube adapted for animals in terrestrial ecosystems, allowing for holistic comparison of three-dimensional ecospace occupation through time. Using our novel terrestrial ecospace model in concert with the well-established marine ecospace model, we compared how ecospace occupation changes and differs between the terrestrial and marine communities across during the Permian-Triassic mass extinction (PTME), the end-Triassic mass extinction (ETME), and in modern environments impacted by climate change. For the PTME and ETME, we utilized the Paleobiology Database, and for our modern analyses, we integrated data from the Global Biodiversity Information Facility and Ocean Biodiversity Information System with extinction threat assessed from the International Union for Conservation of Nature. By establishing consistent comparative models to assess global functional ecospace changes through mass extinction events, our data from the fossil record can help predict and manage changes in modern marine and terrestrial ecospace in response to today’s worsening biotic crisis.