title: Physiological niche and geographical range in European diving beetles (Coleoptera: Dytiscidae).
abstract: Geographical ranges vary greatly in size and position, even within recent clades, but the factors driving this remain poorly understood. In aquatic beetles, thermal niche has been shown to be related to both the relative range size and position of congeners but whether other physiological parameters play a role is unknown. Metabolic plasticity may be critical for species occupying more variable thermal environments and maintaining this plasticity may trade-off against other physiological processes such as immunocompetence. Here we combine data on thermal physiology with measures of metabolic plasticity and immunocompetence to explore these relationships in Deronectes (Dytiscidae). While variation in latitudinal range extent and position was explained in part by thermal physiology, aspects of metabolic plasticity and immunocompetence also appeared important. Northerly distributed, wide-ranging species apparently used different energy reserves under thermal stress from southern endemic congeners and differed in their antibacterial defences. This is the first indication that these processes may be related to geographical range, and suggests parameters that may be worthy of exploration in other taxa.
authors.affiliation: Ecology, Behaviour and Evolution Research Group, School of Biological Sciences, Plymouth University, Plymouth, UK Marine Biology and Ecology Research Centre, School of Marine Science and Engineering, Plymouth University, Plymouth, UK rebekah.cioffi@plymouth.ac.uk.
authors.forename: Rebekah
authors.identifier: 0000-0001-8553-4340
authors.initials: R
authors.lastname: Cioffi
authors.affiliation: Ecology, Behaviour and Evolution Research Group, School of Biological Sciences, Plymouth University, Plymouth, UK.
authors.forename: A John
authors.initials: AJ
authors.lastname: Moody
authors.affiliation: Department of Ecology and Hydrology, University of Murcia, Murcia, Spain.
authors.forename: Andrés
authors.initials: A
authors.lastname: Millán
authors.affiliation: Ecology, Behaviour and Evolution Research Group, School of Biological Sciences, Plymouth University, Plymouth, UK.
authors.forename: Richard A
authors.initials: RA
authors.lastname: Billington
authors.affiliation: Marine Biology and Ecology Research Centre, School of Marine Science and Engineering, Plymouth University, Plymouth, UK.
authors.forename: David T
authors.initials: DT
authors.lastname: Bilton
mesh_terms: D063147:Animal Distribution; D000818:Animals; D001517:Coleoptera / Q000276:immunology / Q000378:metabolism*; D017753:Ecosystem; D005060:Europe; D005843:Geography; D058974:Phylogeography; D013696:Temperature
keywords: biogeography; immunity; macroecology/macrophysiology; metabolism; niche breadth hypothesis; thermal tolerance