title: Hypersalinity drives physiological and morphological changes in Limia perugiae (Poeciliidae).
abstract: A fundamental question in biology is how an organism's morphology and physiology are shaped by its environment. Here, we evaluate the effects of a hypersaline environment on the morphology and physiology of a population of livebearing fish in the genus Limia (Poeciliidae). We sampled from two populations of Limia perugiae (one freshwater and one hypersaline) in the southwest Dominican Republic. We evaluated relative abundance of osmoregulatory proteins using western blot analyses and used a geometric morphometric approach to evaluate fine-scale changes to size and shape. Our data show that gill tissue isolated from hypersaline fish contained approximately two and a half times higher expression of Na(+)/K(+) ATPase proteins. We also show evidence for mitochondrial changes within the gills, with eight times more complex I and four times higher expression of ATP synthase within the gill tissue from the hypersaline population. The energetic consequences to Limia living in saline and hypersaline environments may be a driver for phenotypic diversity, reducing the overall body size and changing the relative size and shape of the head, as well as impeding the growth of secondary sex features among the males.
authors.affiliation: Department of Biology, University of La Verne, 1950 3rd St., La Verne, CA 91750, USA pweaver@laverne.edu.
authors.forename: Pablo F
authors.identifier: http://orcid.org/0000-0003-1576-1366
authors.initials: PF
authors.lastname: Weaver
authors.affiliation: Department of Biology, University of La Verne, 1950 3rd St., La Verne, CA 91750, USA.
authors.forename: Oscar
authors.initials: O
authors.lastname: Tello
authors.affiliation: Herbarium, Library, Art & Archives Directorate, Royal Botanic Gardens, Kew, Richmond, Surrey TW9 3AE, UK.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Krieger
authors.affiliation: Instituto de Investigaciones Botánicas y Zoológicas Prof. Rafael M. Moscoso, Universidad Autónoma de Santo Domingo, Santo Domingo, Dominican Republic.
authors.forename: Arlen
authors.initials: A
authors.lastname: Marmolejo
authors.affiliation: Department of Biology, University of La Verne, 1950 3rd St., La Verne, CA 91750, USA.
authors.forename: Kathleen F
authors.initials: KF
authors.lastname: Weaver
authors.affiliation: Department of Biology, University of La Verne, 1950 3rd St., La Verne, CA 91750, USA.
authors.forename: Jerome V
authors.initials: JV
authors.lastname: Garcia
authors.affiliation: Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO 80309-0334, USA.
authors.forename: Alexander
authors.initials: A
authors.lastname: Cruz
keywords: Geometric morphometrics; Hypersalinity; Mitochondria; Osmoregulation; Poeciliidae