Environmental correlates of adaptive diversification in post‐glacial freshwater fishes

Tiddy, I. C., Schneider, K. and Elmer, K. R. (2023) Environmental correlates of adaptive diversification in post‐glacial freshwater fishes. Journal of Fish Biology, (doi: 10.1111/jfb.15621) (PMID:37984834) (Early Online Publication)

Abstract

Determining how environmental conditions contribute to divergence among populations and drive speciation is fundamental to resolving mechanisms and understanding outcomes in evolutionary biology. Postglacial freshwater fish species in the northern hemisphere are ideal biological systems to explore the effects of environment on diversification in morphology, ecology, and genetics (ecomorph divergences) within lakes. To date, various environmental factors have been implicated in the presence of multiple ecomorphs within particular lakes or regions. However, concerted evidence for generalisable patterns in environmental variables associated with speciation across geographical regions and across species and genera has been lacking. Here, we aimed to identify key biotic and abiotic factors associated with ecological divergence of postglacial freshwater fish species into multiple sympatric ecomorphs, focusing on species in the well-studied, widespread, and co-distributed genera Gasterosteus, Salvelinus, and Coregonus (stickleback, charr, and whitefish). We found that the presence of multiple sympatric ecomorphs tended to be associated with increasing lake surface area size, maximum depth, and nutrient availability. In addition, predation, competition, and prey availability were suggested to play a role in divergence into multiple ecomorphs, but the effects of biotic factors require further study. While we identified several environmental factors correlated with the presence of multiple ecomorphs, there were substantial data gaps across species and regions. An improved understanding of these systems may provide insight into both generalisable environmental factors involved in speciation in other systems, and potential ecological and evolutionary responses of species complexes when these variables are altered by environmental change.

• Item Type: Articles
• Keywords: Ecotype, speciation, ecomorph, salmonid, stickleback, lake, specialist, adaptive divergence.
• Status: Early Online Publication
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Elmer, Professor Kathryn and Schneider, Mr Kevin and Tiddy, Isabelle
• Authors: Tiddy, I. C., Schneider, K., and Elmer, K. R.
• College/School: College of Medical Veterinary and Life Sciences > School of Biodiversity, One Health & Veterinary Medicine
• Journal Name: Journal of Fish Biology
• Publisher: Wiley
• ISSN: 0022-1112
• ISSN (Online): 1095-8649
• Published Online: 20 November 2023
• Copyright Holders: Copyright © 2023 The Authors
• First Published: First published in Journal of Fish Biology 2023
• Publisher Policy: Reproduced under a Creative Commons License
• Data DOI: 10.5525/gla.researchdata.1526