Hybridization in the Fringed Orchids: An Analysis of Species Boundaries in the Face of Gene Flow
Natural hybridization between closely related species in sympatry is an evolutionary process that is common in orchids. Once seen as a threat to parent species, interspecific genetic change is increasingly viewed as a source of novel variation in some ecological contexts. Terrestrial fringed orchids...
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| Format: | Article |
| Language: | English |
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MDPI AG
2023-03-01
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| Series: | Diversity |
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| Online Access: | https://www.mdpi.com/1424-2818/15/3/384 |
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| author | Simone A. Evans Dennis F. Whigham Ida Hartvig Melissa K. McCormick |
| author_facet | Simone A. Evans Dennis F. Whigham Ida Hartvig Melissa K. McCormick |
| author_sort | Simone A. Evans |
| collection | DOAJ |
| description | Natural hybridization between closely related species in sympatry is an evolutionary process that is common in orchids. Once seen as a threat to parent species, interspecific genetic change is increasingly viewed as a source of novel variation in some ecological contexts. Terrestrial fringed orchids in the genus <i>Platanthera</i> contain several clades with high genetic compatibility among species and many putative hybrids. We used biallelic SNPs generated with 3RAD sequencing to study the hybrid complex formed from the parent species <i>P. blephariglottis, P. ciliaris,</i> and <i>P. cristata</i> with high resolution. The genetic structure and phylogenetic relationship of the hybrid complex revealed site-dependent gene flow between species. We documented extensive hybridization and cryptic hybrids in sympatric sites. Interspecific genetic exchange is particularly common between <i>P. blephariglottis</i> and <i>P. ciliaris</i>, with cryptic hybrids among putative <i>P. ciliaris</i> samples being more common than parental assignments in sympatric sites. Hybridization across the triad species complex can reticulate lineages and introduce adaptive alleles. Conversely, it can reduce diversification rates and introduce maladaptive alleles. Investigation into whether anthropogenic forces are eroding species boundaries, particularly the permeable <i>P. blephariglottis</i> and <i>P. ciliaris</i> boundary, is appropriate for conservation efforts. |
| first_indexed | 2024-03-11T06:40:47Z |
| format | Article |
| id | doaj.art-59dbf794f7c444c69bf7933d1ec35169 |
| institution | Directory Open Access Journal |
| issn | 1424-2818 |
| language | English |
| last_indexed | 2024-03-11T06:40:47Z |
| publishDate | 2023-03-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Diversity |
| spelling | doaj.art-59dbf794f7c444c69bf7933d1ec351692023-11-17T10:37:53ZengMDPI AGDiversity1424-28182023-03-0115338410.3390/d15030384Hybridization in the Fringed Orchids: An Analysis of Species Boundaries in the Face of Gene FlowSimone A. Evans0Dennis F. Whigham1Ida Hartvig2Melissa K. McCormick3Smithsonian Environmental Research Center, 647 Contees Wharf Rd, Edgewater, MD 21037, USASmithsonian Environmental Research Center, 647 Contees Wharf Rd, Edgewater, MD 21037, USASmithsonian Environmental Research Center, 647 Contees Wharf Rd, Edgewater, MD 21037, USASmithsonian Environmental Research Center, 647 Contees Wharf Rd, Edgewater, MD 21037, USANatural hybridization between closely related species in sympatry is an evolutionary process that is common in orchids. Once seen as a threat to parent species, interspecific genetic change is increasingly viewed as a source of novel variation in some ecological contexts. Terrestrial fringed orchids in the genus <i>Platanthera</i> contain several clades with high genetic compatibility among species and many putative hybrids. We used biallelic SNPs generated with 3RAD sequencing to study the hybrid complex formed from the parent species <i>P. blephariglottis, P. ciliaris,</i> and <i>P. cristata</i> with high resolution. The genetic structure and phylogenetic relationship of the hybrid complex revealed site-dependent gene flow between species. We documented extensive hybridization and cryptic hybrids in sympatric sites. Interspecific genetic exchange is particularly common between <i>P. blephariglottis</i> and <i>P. ciliaris</i>, with cryptic hybrids among putative <i>P. ciliaris</i> samples being more common than parental assignments in sympatric sites. Hybridization across the triad species complex can reticulate lineages and introduce adaptive alleles. Conversely, it can reduce diversification rates and introduce maladaptive alleles. Investigation into whether anthropogenic forces are eroding species boundaries, particularly the permeable <i>P. blephariglottis</i> and <i>P. ciliaris</i> boundary, is appropriate for conservation efforts.https://www.mdpi.com/1424-2818/15/3/384<i>Platanthera</i>population genomicsorchidHybridizationadmixturehybrid zone |
| spellingShingle | Simone A. Evans Dennis F. Whigham Ida Hartvig Melissa K. McCormick Hybridization in the Fringed Orchids: An Analysis of Species Boundaries in the Face of Gene Flow Diversity <i>Platanthera</i> population genomics orchid Hybridization admixture hybrid zone |
| title | Hybridization in the Fringed Orchids: An Analysis of Species Boundaries in the Face of Gene Flow |
| title_full | Hybridization in the Fringed Orchids: An Analysis of Species Boundaries in the Face of Gene Flow |
| title_fullStr | Hybridization in the Fringed Orchids: An Analysis of Species Boundaries in the Face of Gene Flow |
| title_full_unstemmed | Hybridization in the Fringed Orchids: An Analysis of Species Boundaries in the Face of Gene Flow |
| title_short | Hybridization in the Fringed Orchids: An Analysis of Species Boundaries in the Face of Gene Flow |
| title_sort | hybridization in the fringed orchids an analysis of species boundaries in the face of gene flow |
| topic | <i>Platanthera</i> population genomics orchid Hybridization admixture hybrid zone |
| url | https://www.mdpi.com/1424-2818/15/3/384 |
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