Phylogenetic patterns and the adaptive evolution of osmoregulation in fiddler crabs (Brachyura, Uca)

Authors

Samuel Coelho Faria, Universidade de São PauloFollow
Diogo Borges Provete, Universidade Federal de São CarlosFollow
Carl Leo Thurman, University of Northern IowaFollow
John Campbell McNamara, Universidade de São PauloFollow

Document Type

Article

Keywords

Salinity, Phylogenetics, Crabs, Evolutionary physiology, Phylogenetic analysis, Secretion, Habitats, Gills

Journal/Book/Conference Title

PLoS One

Volume

12

Issue

2

Abstract

Salinity is the primary driver of osmoregulatory evolution in decapods, and may have influenced their diversification into different osmotic niches. In semi-terrestrial crabs, hyperosmoregulatory ability favors sojourns into burrows and dilute media, and provides a safeguard against hemolymph dilution; hypo-osmoregulatory ability underlies emersion capability and a life more removed from water sources. However, most comparative studies have neglected the roles of the phylogenetic and environmental components of inter-specific physiological variation, hindering evaluation of phylogenetic patterns and the adaptive nature of osmoregulatory evolution. Semi-terrestrial fiddler crabs (Uca) inhabit fresh to hyper-saline waters, with species from the Americas occupying higher intertidal habitats than Indo-west Pacific species mainly found in the low intertidal zone. Here, we characterize numerous osmoregulatory traits in all ten fiddler crabs found along the Atlantic coast of Brazil, and we employ phylogenetic comparative methods using 24 species to test for: (i) similarities of osmoregulatory ability among closely related species; (ii) salinity as a driver of osmoregulatory evolution; (iii) correlation between salt uptake and secretion; and (iv) adaptive peaks in osmoregulatory ability in the high intertidal American lineages. Our findings reveal that osmoregulation in Uca exhibits strong phylogenetic patterns in salt uptake traits. Salinity does not correlate with hyper/hypo-regulatory abilities, but drives hemolymph osmolality at ambient salinities. Osmoregulatory traits have evolved towards three adaptive peaks, revealing a significant contribution of hyper/hypo-regulatory ability in the American clades. Thus, during the evolutionary history of fiddler crabs, salinity has driven some of the osmoregulatory transformations that underpin habitat diversification, although others are apparently constrained phylogenetically.

Department

Department of Biology

Comments

First published in PLoS ONE, v.12 n.2 (2017) e0171870, published by the Public Library of Science. DOI: http://dx.doi.org/10.1371/journal.pone.0171870

Original Publication Date

2-2017

DOI of published version

10.1371/journal.pone.0171870

Repository

UNI ScholarWorks, University of Northern Iowa, Rod Library

Date Digital

2017

Copyright

©2017 Faria et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.

Language

EN

File Format

application/pdf

Recommended Citation

Faria, Samuel Coelho; Provete, Diogo Borges; Thurman, Carl Leo; and McNamara, John Campbell, "Phylogenetic patterns and the adaptive evolution of osmoregulation in fiddler crabs (Brachyura, Uca)" (2017). Faculty Publications. 14.
https://scholarworks.uni.edu/bio_facpub/14