292-8 The Curious Case of the Caribbean Carnivores

Session: Life and Environments Through Time and Space: Multi-Record Approaches to Stratigraphic Paleobiology, Part II

Presenting Author:

Authors:

Abstract:

Understanding the mechanisms by which the physical environment impacts biological communities provides essential context for how we decipher and predict system function in our rapidly changing world. One way to explore these mechanisms is to study the response of ancient communities to past physical system changes. In the Neogene western Caribbean, environmental change initiated by the formation of the Isthmus of Panama led to oceanographic change and the restructuring of benthic marine communities and emergence of the modern Caribbean fauna. In this study, we detail and revisit changing ecologies in the gastropod community, with particular focus on feeding strategy through time. 

Here, we quantify relative abundances of gastropod trophic groups across seventy bulk sampling locations in Panama and Costa Rica. Samples ranged in age from 11 million years to ~7000 yrs BP. We identified individual specimens to the genus level and then assigned each genus to a trophic group based on diet, mobility, and relationship to the substrate, as defined in the Neogene Marine Biota of Tropical America (NMITA) database. Previous work on gastropod ecology suggests that declines in abundance of carnivorous gastropods are expected with decreasing productivity in the Caribbean; therefore, we paid particular attention to carnivore abundance. We examined trends in carnivore abundance both as a broadly-defined functional group, but we also analyzed more nuanced trends in types of carnivorous gastropods (e.g. active predators versus scavengers). Our data support the broad hypothesis that carnivores decrease through time as planktonic productivity plumets in the Caribbean, however, not all broadly defined carnivorous groups follow this trend, providing additional insight into this changing ecosystem. This research illustrates how understanding changes in the ecology and functional diversity of an ecosystem in response to environmental perturbations contributes to greater understanding of the larger mechanisms that connect environmental and biological changes. 

Geological Society of America Abstracts with Program. Vol. 57, No. 6, 2025

doi: 10.1130/abs/2025AM-9382

© Copyright 2025 The Geological Society of America (GSA), all rights reserved.