title: Deep-sea diversity patterns are shaped by energy availability.
abstract: The deep ocean is the largest and least-explored ecosystem on Earth, and a uniquely energy-poor environment. The distribution, drivers and origins of deep-sea biodiversity remain unknown at global scales. Here we analyse a database of more than 165,000 distribution records of Ophiuroidea (brittle stars), a dominant component of sea-floor fauna, and find patterns of biodiversity unlike known terrestrial or coastal marine realms. Both patterns and environmental predictors of deep-sea (2,000-6,500 m) species richness fundamentally differ from those found in coastal (0-20 m), continental shelf (20-200 m), and upper-slope (200-2,000 m) waters. Continental shelf to upper-slope richness consistently peaks in tropical Indo-west Pacific and Caribbean (0-30°) latitudes, and is well explained by variations in water temperature. In contrast, deep-sea species show maximum richness at higher latitudes (30-50°), concentrated in areas of high carbon export flux and regions close to continental margins. We reconcile this structuring of oceanic biodiversity using a species-energy framework, with kinetic energy predicting shallow-water richness, while chemical energy (export productivity) and proximity to slope habitats drive deep-sea diversity. Our findings provide a global baseline for conservation efforts across the sea floor, and demonstrate that deep-sea ecosystems show a biodiversity pattern consistent with ecological theory, despite being different from other planetary-scale habitats.
authors.affiliation: Museum Victoria, GPO Box 666, Melbourne, Victoria 3001, Australia.|Quantitative and Applied Ecology Group, School of Biological Sciences, BioSciences Building 2, The University of Melbourne, Victoria 3010, Australia.
authors.forename: Skipton N C
authors.initials: SN
authors.lastname: Woolley
authors.affiliation: Department of Biology, Dalhousie University, 1355 Oxford Street, Halifax B3H 4J1, Canada.|United Nations Environment Programme World Conservation Monitoring Centre, 219 Huntingdon Road, Cambridge CB3 0DL, UK.
authors.forename: Derek P
authors.initials: DP
authors.lastname: Tittensor
authors.affiliation: CSIRO, Wealth from Oceans Flagship, Hobart, Tasmania 7000, Australia.
authors.forename: Piers K
authors.initials: PK
authors.lastname: Dunstan
authors.affiliation: Quantitative and Applied Ecology Group, School of Biological Sciences, BioSciences Building 2, The University of Melbourne, Victoria 3010, Australia.
authors.forename: Gurutzeta
authors.initials: G
authors.lastname: Guillera-Arroita
authors.affiliation: Quantitative and Applied Ecology Group, School of Biological Sciences, BioSciences Building 2, The University of Melbourne, Victoria 3010, Australia.
authors.forename: José J
authors.initials: JJ
authors.lastname: Lahoz-Monfort
authors.affiliation: Quantitative and Applied Ecology Group, School of Biological Sciences, BioSciences Building 2, The University of Melbourne, Victoria 3010, Australia.
authors.forename: Brendan A
authors.initials: BA
authors.lastname: Wintle
authors.affiliation: Department of Biology, Dalhousie University, 1355 Oxford Street, Halifax B3H 4J1, Canada.
authors.forename: Boris
authors.initials: B
authors.lastname: Worm
authors.affiliation: Museum Victoria, GPO Box 666, Melbourne, Victoria 3001, Australia.
authors.forename: Timothy D
authors.initials: TD
authors.lastname: O'Hara
mesh_terms: D000818:Animals; D059001:Aquatic Organisms / Q000302:isolation & purification* / Q000378:metabolism*; D044822:Biodiversity; D003247:Conservation of Natural Resources; D004447:Echinodermata / Q000378:metabolism*; D004734:Energy Metabolism; D009792:Oceans and Seas; D012623:Seawater; D013696:Temperature; D014329:Tropical Climate