Cargando…

We get by with a little help from our friends: shared adaptive variation provides a bridge to novel ecological specialists during adaptive radiation

Adaptive radiations involve astounding bursts of phenotypic, ecological and species diversity. However, the microevolutionary processes that underlie the origins of these bursts are still poorly understood. We report the discovery of an intermediate C. sp. ‘wide-mouth’ scale-eating ecomorph in a sym...

Descripción completa

Detalles Bibliográficos
Autores principales: Richards, Emilie J., Martin, Christopher H.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: The Royal Society 2022
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9130792/
https://www.ncbi.nlm.nih.gov/pubmed/35611537
http://dx.doi.org/10.1098/rspb.2022.0613
_version_ 1784713048289705984
author Richards, Emilie J.
Martin, Christopher H.
author_facet Richards, Emilie J.
Martin, Christopher H.
author_sort Richards, Emilie J.
collection PubMed
description Adaptive radiations involve astounding bursts of phenotypic, ecological and species diversity. However, the microevolutionary processes that underlie the origins of these bursts are still poorly understood. We report the discovery of an intermediate C. sp. ‘wide-mouth’ scale-eating ecomorph in a sympatric radiation of Cyprinodon pupfishes, illuminating the transition from a widespread algae-eating generalist to a novel microendemic scale-eating specialist. We first show that this ecomorph occurs in sympatry with generalist C. variegatus and scale-eating specialist C. desquamator on San Salvador Island, Bahamas, but is genetically differentiated, morphologically distinct and often consumes scales. We then compared the timing of selective sweeps on shared and unique adaptive variants in trophic specialists to characterize their adaptive walk. Shared adaptive regions swept first in both the specialist desquamator and the intermediate ‘wide-mouth’ ecomorph, followed by unique sweeps of introgressed variation in ‘wide-mouth’ and de novo variation in desquamator. The two scale-eating populations additionally shared 9% of their hard selective sweeps with the molluscivore C. brontotheroides, despite no single common ancestor among specialists. Our work provides a new microevolutionary framework for investigating how major ecological transitions occur and illustrates how both shared and unique genetic variation can provide a bridge for multiple species to access novel ecological niches.
format Online
Article
Text
id pubmed-9130792
institution National Center for Biotechnology Information
language English
publishDate 2022
publisher The Royal Society
record_format MEDLINE/PubMed
spelling pubmed-91307922022-05-31 We get by with a little help from our friends: shared adaptive variation provides a bridge to novel ecological specialists during adaptive radiation Richards, Emilie J. Martin, Christopher H. Proc Biol Sci Evolution Adaptive radiations involve astounding bursts of phenotypic, ecological and species diversity. However, the microevolutionary processes that underlie the origins of these bursts are still poorly understood. We report the discovery of an intermediate C. sp. ‘wide-mouth’ scale-eating ecomorph in a sympatric radiation of Cyprinodon pupfishes, illuminating the transition from a widespread algae-eating generalist to a novel microendemic scale-eating specialist. We first show that this ecomorph occurs in sympatry with generalist C. variegatus and scale-eating specialist C. desquamator on San Salvador Island, Bahamas, but is genetically differentiated, morphologically distinct and often consumes scales. We then compared the timing of selective sweeps on shared and unique adaptive variants in trophic specialists to characterize their adaptive walk. Shared adaptive regions swept first in both the specialist desquamator and the intermediate ‘wide-mouth’ ecomorph, followed by unique sweeps of introgressed variation in ‘wide-mouth’ and de novo variation in desquamator. The two scale-eating populations additionally shared 9% of their hard selective sweeps with the molluscivore C. brontotheroides, despite no single common ancestor among specialists. Our work provides a new microevolutionary framework for investigating how major ecological transitions occur and illustrates how both shared and unique genetic variation can provide a bridge for multiple species to access novel ecological niches. The Royal Society 2022-05-25 2022-05-25 /pmc/articles/PMC9130792/ /pubmed/35611537 http://dx.doi.org/10.1098/rspb.2022.0613 Text en © 2022 The Authors. https://creativecommons.org/licenses/by/4.0/Published by the Royal Society under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/4.0/ (https://creativecommons.org/licenses/by/4.0/) , which permits unrestricted use, provided the original author and source are credited.
spellingShingle Evolution
Richards, Emilie J.
Martin, Christopher H.
We get by with a little help from our friends: shared adaptive variation provides a bridge to novel ecological specialists during adaptive radiation
title We get by with a little help from our friends: shared adaptive variation provides a bridge to novel ecological specialists during adaptive radiation
title_full We get by with a little help from our friends: shared adaptive variation provides a bridge to novel ecological specialists during adaptive radiation
title_fullStr We get by with a little help from our friends: shared adaptive variation provides a bridge to novel ecological specialists during adaptive radiation
title_full_unstemmed We get by with a little help from our friends: shared adaptive variation provides a bridge to novel ecological specialists during adaptive radiation
title_short We get by with a little help from our friends: shared adaptive variation provides a bridge to novel ecological specialists during adaptive radiation
title_sort we get by with a little help from our friends: shared adaptive variation provides a bridge to novel ecological specialists during adaptive radiation
topic Evolution
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9130792/
https://www.ncbi.nlm.nih.gov/pubmed/35611537
http://dx.doi.org/10.1098/rspb.2022.0613
work_keys_str_mv AT richardsemiliej wegetbywithalittlehelpfromourfriendssharedadaptivevariationprovidesabridgetonovelecologicalspecialistsduringadaptiveradiation
AT martinchristopherh wegetbywithalittlehelpfromourfriendssharedadaptivevariationprovidesabridgetonovelecologicalspecialistsduringadaptiveradiation