title: Consequences of biodiversity loss diverge from expectation due to post-extinction compensatory responses.
abstract: Consensus has been reached that global biodiversity loss impairs ecosystem functioning and the sustainability of services beneficial to humanity. However, the ecosystem consequences of extinction in natural communities are moderated by compensatory species dynamics, yet these processes are rarely accounted for in impact assessments and seldom considered in conservation programmes. Here, we use marine invertebrate communities to parameterise numerical models of sediment bioturbation - a key mediator of biogeochemical cycling - to determine whether post-extinction compensatory mechanisms alter biodiversity-ecosystem function relations following non-random extinctions. We find that compensatory dynamics lead to trajectories of sediment mixing that diverge from those without compensation, and that the form, magnitude and variance of each probabilistic distribution is highly influenced by the type of compensation and the functional composition of surviving species. Our findings indicate that the generalized biodiversity-function relation curve, as derived from multiple empirical investigations of random species loss, is unlikely to yield representative predictions for ecosystem properties in natural systems because the influence of post-extinction community dynamics are under-represented. Recognition of this problem is fundamental to management and conservation efforts, and will be necessary to ensure future plans and adaptation strategies minimize the adverse impacts of the biodiversity crisis.
authors.affiliation: Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton Waterfront Campus, European Way, Southampton. SO14 3ZH, UK.
authors.forename: Matthias S
authors.initials: MS
authors.lastname: Thomsen
authors.affiliation: Cefas Laboratory, Pakefield Road, Lowestoft, Suffolk, NR33 0HT, UK.
authors.forename: Clement
authors.initials: C
authors.lastname: Garcia
authors.affiliation: Cefas Laboratory, Pakefield Road, Lowestoft, Suffolk, NR33 0HT, UK.
authors.forename: Stefan G
authors.initials: SG
authors.lastname: Bolam
authors.affiliation: Cefas Laboratory, Pakefield Road, Lowestoft, Suffolk, NR33 0HT, UK.
authors.forename: Ruth
authors.initials: R
authors.lastname: Parker
authors.affiliation: Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton Waterfront Campus, European Way, Southampton. SO14 3ZH, UK.|Biological Sciences, University of Southampton, Highfield Campus, Southampton. SO17 1BJ, UK.
authors.forename: Jasmin A
authors.initials: JA
authors.lastname: Godbold
authors.affiliation: Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton Waterfront Campus, European Way, Southampton. SO14 3ZH, UK.
authors.forename: Martin
authors.initials: M
authors.lastname: Solan
mesh_terms: D000818:Animals; D044822:Biodiversity; D017753:Ecosystem; D053476:Extinction, Biological; D007448:Invertebrates