{"doi":"10.1002/ece3.3893","title":"Rapid sexual and genomic isolation in sympatric<i>Drosophila</i>without reproductive character displacement","abstract":"<jats:title>Abstract</jats:title><jats:p>The rapid evolution of sexual isolation in sympatry has long been associated with reinforcement (i.e., selection to avoid maladaptive hybridization). However, there are many species pairs in sympatry that have evolved rapid sexual isolation without known costs to hybridization. A major unresolved question is what evolutionary processes are involved in driving rapid speciation in such cases. Here, we focus on one such system; the<jats:italic>Drosophila athabasca</jats:italic>species complex, which is composed of three partially sympatric and interfertile semispecies:<jats:styled-content style=\"fixed-case\">WN</jats:styled-content>,<jats:styled-content style=\"fixed-case\">EA</jats:styled-content>, and<jats:styled-content style=\"fixed-case\">EB</jats:styled-content>. To study speciation in this species complex, we assayed sexual and genomic isolation within and between these semispecies in both sympatric and allopatric populations. First, we found no evidence of reproductive character displacement (<jats:styled-content style=\"fixed-case\">RCD</jats:styled-content>) in sympatric zones compared to distant allopatry. Instead, semispecies were virtually completely sexually isolated from each other across their entire ranges. Moreover, using spatial approaches and coalescent demographic simulations, we detected either zero or only weak heterospecific gene flow in sympatry. In contrast, within each semispecies we found only random mating and little population genetic structure, except between highly geographically distant populations. Finally, we determined that speciation in this system is at least an order of magnitude older than previously assumed, with<jats:styled-content style=\"fixed-case\">WN</jats:styled-content>diverging first, around 200K years ago, and<jats:styled-content style=\"fixed-case\">EA</jats:styled-content>and<jats:styled-content style=\"fixed-case\">EB</jats:styled-content>diverging 100K years ago. In total, these results suggest that these semispecies should be given full species status and we adopt new nomenclature:<jats:styled-content style=\"fixed-case\">WN</jats:styled-content>—<jats:italic>D. athabasca</jats:italic>,<jats:styled-content style=\"fixed-case\">EA</jats:styled-content>—<jats:italic>D. mahican</jats:italic>, and<jats:styled-content style=\"fixed-case\">EB</jats:styled-content>—<jats:italic>D. lenape</jats:italic>. While the lack of<jats:styled-content style=\"fixed-case\">RCD</jats:styled-content>in sympatry and interfertility do not support reinforcement, we discuss what additional evidence is needed to further decipher the mechanisms that caused rapid speciation in this species complex.</jats:p>","journal":"Ecology and Evolution","year":2018,"id":35263,"datarank":0.39792131153452154,"base_score":2.4849066497880004,"endowment":2.4849066497880004,"self_citation_contribution":0.37273599746820013,"citation_network_contribution":0.02518531406632139,"self_endowment_contribution":0.37273599746820013,"citer_contribution":0.02518531406632139,"corpus_percentile":null,"corpus_rank":null,"citation_count":11,"citer_count":5,"citers_with_citation_signal":3,"citers_with_endowment":3,"datacite_reuse_total":2,"is_dataset":false,"is_dataset_confidence":null,"is_oa":false,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":null,"fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":180989,"name":"Luana S. Maroja","orcid":null,"position":1,"is_corresponding":false},{"id":180990,"name":"Kim Nguyen","orcid":null,"position":2,"is_corresponding":false},{"id":180991,"name":"Syed Hussain","orcid":null,"position":3,"is_corresponding":false},{"id":180992,"name":"Preethi Kumaran","orcid":null,"position":4,"is_corresponding":false},{"id":180988,"name":"Roman Yukilevich","orcid":"0000-0002-2426-839X","position":0,"is_corresponding":false}],"reference_count":0,"raw_metadata":{"has_enrichment":true,"base_score":2.4849066497880004,"endowment":2.4849066497880004,"datacite_reuse_total":2,"file_count":0,"downloads":0,"views":0,"has_version_chain":false,"is_dataset":false,"is_oa":false,"pmid":"29531700","pmcid":"PMC5838044","openalex_id":"https://openalex.org/W2792293161","authors":[],"funders":[{"funder_name":"National Science Foundation","grant_id":"1655935","title":null}],"total_grants":1,"fwci":0.7167,"citation_percentile":0.74999311,"influential_citations":0,"citation_trend":[{"year":2018,"count":1},{"year":2019,"count":1},{"year":2021,"count":2},{"year":2022,"count":2},{"year":2024,"count":2},{"year":2025,"count":1},{"year":2026,"count":2}],"oa_status":"gold","license":"cc-by","oa_locations":[{"url":"https://onlinelibrary.wiley.com/doi/pdfdirect/10.1002/ece3.3893","host_type":"journal"},{"url":"https://doi.org/10.1002/ece3.3893","host_type":"GOLD"},{"url":"https://onlinelibrary.wiley.com/doi/pdfdirect/10.1002/ece3.3893","host_type":"publisher"},{"url":"https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fece3.3893","host_type":"publisher"},{"url":"https://onlinelibrary.wiley.com/doi/pdf/10.1002/ece3.3893","host_type":"publisher"},{"url":"https://onlinelibrary.wiley.com/doi/full-xml/10.1002/ece3.3893","host_type":"publisher"},{"url":"http://api.wiley.com/onlinelibrary/chorus/v1/articles/10.1002%2Fece3.3893","host_type":"publisher"},{"url":"https://pubmed.ncbi.nlm.nih.gov/29531700","host_type":"repository"},{"url":"https://www.ncbi.nlm.nih.gov/pmc/articles/5838044","host_type":"repository"},{"url":"https://europepmc.org/articles/PMC5838044","host_type":"Europe_PMC"},{"url":"https://europepmc.org/articles/PMC5838044?pdf=render","host_type":"Europe_PMC"}],"fields_of_study":["Genetic and phenotypic traits in livestock","Reproductive Physiology in Livestock","Genetic diversity and population structure","Biology","Medicine"],"mesh_terms":[],"keywords":["Sympatric speciation","Character displacement","Character (mathematics)","Biology","Drosophila (subgenus)","Reproductive isolation","Isolation (microbiology)","Evolutionary biology","Zoology","Sympatry","Displacement (psychology)","Genetics","Bioinformatics","Gene","Sociology","Demography","Psychology","Psychoanalysis","Population structure","Gene flow","Secondary Contact","Isolation By Distance","Range Expansions","Genomic Divergence","Sexual Isolation","Reproductive Character Displacement"],"sdg_mappings":[],"linked_datasets":[{"doi":"10.5281/zenodo.18809046","title":"Rapid sexual and genomic isolation in sympatric Drosophila without reproductive character displacement.","publisher":"Zenodo","resource_type":"JournalArticle"},{"doi":"10.5281/zenodo.18809047","title":"Rapid sexual and genomic isolation in sympatric Drosophila without reproductive character displacement.","publisher":"Zenodo","resource_type":"JournalArticle"}],"clinical_trials":[],"software_tools":[],"database_accessions":[{"name":"gen"}],"source":"live","citation_network_status":"fetched"},"created_at":"2026-06-10T02:45:01.741905Z","pmid":null,"pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}