Evolution and effects of ecosystem engineers through the Phanerozoic

Alison Cribb, University of Southampton Cambridge Fluids Network - fluids-related seminars 25 February 2025 12:00pm Department of Earth Sciences, Tilley Lecture Theatre Ecosystem engineers are organisms whose behaviours change the physical characteristics of their habitats and modulate resource availability, thereby impacting the habitability of their environments for other biota. Given their profound impacts on ecological and evolutionary processes in the modern, palaeobiologists have long hypothesized that the rise of ecosystem engineers throughout Earth history has had increasingly positive impacts on the biosphere, contributing to the rise in marine biodiversity observed over the Phanerozoic. Here, I will highlight the role that animal ecosystem engineers have played in shaping ecological and environmental landscapes since the Ediacaran-Cambrian transition. Focusing on bioturbation, I will present how ecologically-informed biogeochemical modelling is used to show how evolutionary innovations and the environment work together to modulate an ecosystem engineer’s effects. Broadening timescales and ecological groups, I will also present new evidence using ecological meta-analyses that demonstrates that marine ecosystem engineers have had persistent strong positive effects on biodiversity over the entire Phanerozoic. Finally, I will propose a new framework for “Earth systems engineers” (ESE) – ecosystem engineer-type organisms whose activities play major roles in global resource cycles – and highlight major ESE innovations, transitions, and effects.