Bringing together data across animal species and landscape contexts, Gemma Harvey addresses the fundamental question of whether there is a geomorphological signature of life
Understanding when and how life leaves a geomorphological signature within landscapes is a major research challenge for the field of biogeomorphology – which explores the interactions between living organisms and earth surface processes and landforms. The role of animals in the evolution of landforms and landscapes is greater than is widely recognised, and has major implications for environmental resilience, restoration and hazards. Animals acting as ‘zoogeomorphic agents’ can engineer geomorphological processes in diverse ways, and across a wide range of space and time scales.
Shaping of landscapes and landforms by larger or more charismatic animals is sometimes better known, for example beaver dams transforming the character of entire river-landscape systems, and salmon spawning influencing river evolution over geological timescales. Yet smaller and less conspicuous animals can also have significant effects. For example, freshwater crayfish modify erosion and sediment transport in rivers and ant mounds alter soil erosion in terrestrial landscapes. Animals that modulate geomorphological processes can make important contributions to the recovery or restoration of degraded landscapes, but some invasive species can generate geomorphic hazards or even induce landscape collapse.
Recent years have seen rapid growth in research on the diverse and fascinating ways that animals modify sediment fluxes and contribute to landform and landscape evolution. Yet empirical studies overwhelmingly focus on single species within a specific environmental context. Now, with over four decades of published data available, it is possible to bring together this diverse evidence to explore the nature and significance of geomorphological signatures of life across scales from patches to landscapes, and across animal groups and biomes.
During my Research Fellowship I will carry out a systematic review of published research to establish a novel global data set, ZooGeoData, that captures animal impacts on geomorphological forms and processes across terrestrial and aquatic environments. I will then use this new resource to undertake a comprehensive meta-analysis. My research will uncover the diversity and global distribution of zoogeomorphic agents and the characteristics of their signatures. I will explore how animal traits (such as size, sociality, behaviours, life history and abundance) interact with landscape context to generate different geomorphological signatures. I will assess the magnitude, relevance and persistence of animal impacts on sediment fluxes and landform and landscape change in different environmental contexts. This new understanding will help answer the fundamental question ‘is there a geomorphological signature of life?’.