1
|
Clemens BJ, Schreck CB. An assessment of terminology for intraspecific diversity in fishes, with a focus on "ecotypes" and "life histories". Ecol Evol 2021; 11:10772-10793. [PMID: 34429881 PMCID: PMC8366897 DOI: 10.1002/ece3.7884] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 06/03/2021] [Accepted: 06/23/2021] [Indexed: 12/15/2022] Open
Abstract
Understanding and preserving intraspecific diversity (ISD) is important for species conservation. However, ISD units do not have taxonomic standards and are not universally recognized. The terminology used to describe ISD is varied and often used ambiguously. We compared definitions of terms used to describe ISD with use in recent studies of three fish taxa: sticklebacks (Gasterosteidae), Pacific salmon and trout (Oncorhynchus spp., "PST"), and lampreys (Petromyzontiformes). Life history describes the phenotypic responses of organisms to environments and includes biological parameters that affect population growth or decline. Life-history pathway(s) are the result of different organismal routes of development that can result in different life histories. These terms can be used to describe recognizable life-history traits. Life history is generally used in organismal- and ecology-based journals. The terms paired species/species pairs have been used to describe two different phenotypes, whereas in some species and situations a continuum of phenotypes may be expressed. Our review revealed overlapping definitions for race and subspecies, and subspecies and ecotypes. Ecotypes are genotypic adaptations to particular environments, and this term is often used in genetic- and evolution-based journals. "Satellite species" is used for situations in which a parasitic lamprey yields two or more derived, nonparasitic lamprey species. Designatable Units, Evolutionary Significant Units (ESUs), and Distinct Population Segments (DPS) are used by some governments to classify ISD of vertebrate species within distinct and evolutionary significant criteria. In situations where the genetic or life-history components of ISD are not well understood, a conservative approach would be to call them phenotypes.
Collapse
Affiliation(s)
| | - Carl B. Schreck
- Department of Fisheries and WildlifeOregon State UniversityCorvallisORUSA
| |
Collapse
|
2
|
Rougemont Q, Dolo V, Oger A, Besnard AL, Huteau D, Coutellec MA, Perrier C, Launey S, Evanno G. Riverscape genetics in brook lamprey: genetic diversity is less influenced by river fragmentation than by gene flow with the anadromous ecotype. Heredity (Edinb) 2021; 126:235-250. [PMID: 32989279 PMCID: PMC8027852 DOI: 10.1038/s41437-020-00367-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2019] [Revised: 08/28/2020] [Accepted: 09/01/2020] [Indexed: 01/05/2023] Open
Abstract
Understanding the effect of human-induced landscape fragmentation on gene flow and evolutionary potential of wild populations has become a major concern. Here, we investigated the effect of riverscape fragmentation on patterns of genetic diversity in the freshwater resident European brook lamprey (Lampetra planeri) that has a low ability to pass obstacles to migration. We tested the hypotheses of (i) asymmetric gene flow following water current and (ii) an effect of gene flow with the closely related anadromous river lamprey (L. fluviatilis) ecotype on L. planeri genetic diversity. We genotyped 2472 individuals, including 225 L. fluviatilis, sampled from 81 sites upstream and downstream barriers to migration, in 29 western European rivers. Linear modelling revealed a strong positive relationship between genetic diversity and the distance from the river source, consistent with expected patterns of decreased gene flow into upstream populations. However, the presence of anthropogenic barriers had a moderate effect on spatial genetic structure. Accordingly, we found evidence for downstream-directed gene flow, supporting the hypothesis that barriers do not limit dispersal mediated by water flow. Downstream L. planeri populations in sympatry with L. fluviatilis displayed consistently higher genetic diversity. We conclude that genetic drift and slight downstream gene flow drive the genetic make-up of upstream L. planeri populations whereas gene flow between ecotypes maintains higher levels of genetic diversity in L. planeri populations sympatric with L. fluviatilis. We discuss the implications of these results for the design of conservation strategies of lamprey, and other freshwater organisms with several ecotypes, in fragmented dendritic river networks.
Collapse
Affiliation(s)
- Quentin Rougemont
- ESE, Ecology and Ecosystem Health, INRAE, Agrocampus Ouest, 35042, Rennes, France.
- Département de biologie, Institut de Biologie Intégrative etsu des Systèmes (IBIS), Université Laval, Québec, G1V 0A6, Canada.
| | - Victoria Dolo
- ESE, Ecology and Ecosystem Health, INRAE, Agrocampus Ouest, 35042, Rennes, France
| | - Adrien Oger
- ESE, Ecology and Ecosystem Health, INRAE, Agrocampus Ouest, 35042, Rennes, France
| | - Anne-Laure Besnard
- ESE, Ecology and Ecosystem Health, INRAE, Agrocampus Ouest, 35042, Rennes, France
| | - Dominique Huteau
- ESE, Ecology and Ecosystem Health, INRAE, Agrocampus Ouest, 35042, Rennes, France
| | | | - Charles Perrier
- Centre de Biologie pour la Gestion des Populations UMR CBGP, INRA, CIRAD, IRD, Montpellier SupAgro, Univ Montpellier, Montpellier, France
| | - Sophie Launey
- ESE, Ecology and Ecosystem Health, INRAE, Agrocampus Ouest, 35042, Rennes, France
| | - Guillaume Evanno
- ESE, Ecology and Ecosystem Health, INRAE, Agrocampus Ouest, 35042, Rennes, France
- OFB, INRAE, Agrocampus Ouest, University Pau Pays Adour, Management of Diadromous Fish in their Environment, Rennes, France
| |
Collapse
|