Integrating functional diversity into the global conservation agenda
File(s)
Author(s)
Webster, Ceri
Type
Thesis
Abstract
Biodiversity is declining at an unprecedented rate, driven largely by anthropogenic pressures. This thesis explores the multifaceted nature of biodiversity, focusing on phylogenetic diversity (PD) and functional diversity (FD), to provide insights into the current and future state of global biodiversity. Using comprehensive datasets on sharks, rays, and birds, I examine the relationship between PD and FD, revealing that these facets often diverge, particularly when decoupled from species richness, and are therefore complementary rather than interchangeable. Building on these findings, I develop the FuDGE framework to prioritise species for conservation based on their functional distinctiveness and extinction risk. This framework incorporates intraspecific trait variation, future trait space predictions, and uncertainties in extinction risk, providing a robust tool for identifying species whose loss would result in irreplaceable functional deficits. Applying this framework to sharks highlights 76 species with high functional distinctiveness that are threatened with extinction, offering actionable priorities for conservation efforts. Finally, I introduce a probabilistic approach to quantify expected FD losses under current extinction trajectories. By simulating potential erosion of trait space, I identify vulnerable ecological strategies and regions at heightened risk. This research underscores the urgency of protecting species that contribute disproportionately to FD, especially in marine ecosystems where overexploitation and climate change are accelerating biodiversity loss. The findings presented in this thesis highlight the need to move beyond taxonomic measures to capture the full breadth of biodiversity. By integrating PD and FD metrics, and by prioritising functionally irreplaceable species, this work aims to provide critical tools to inform policy and enhance global conservation strategies. These advances will offer new insights into the global decline of FD and safeguarding ecological strategies essential for human well-being.
Version
Open Access
Date Issued
2024-11-15
Date Awarded
01/02/2025
License URL
Advisor
Rosindell, James
Gumbs, Rikki
Pettorelli, Nathalie
Sponsor
Natural Environment Research Council (Great Britain)
Grant Number
NE/S007415/1
Publisher Department
Department of Life Sciences
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)