Abstract Detail


Alonso, Alejandro [1], Coca, Marina [1], Monjas, David [1], Gallego-Narbón, Angélica  [1], Fernández-Mazuecos, Mario [2], Valcarcel, Virginia [1].

Genotyping-by-sequencing reveals the impact of climatic niche on the successful colonization of Madeira by ivies (Hedera L., Araliaceae).

The genus Hedera L. (ivies) includes 12 vine species naturally distributed throughout Eurasia and northern Africa. Three of them are endemic to Macaronesia: H. azorica Carrière (Azores), H. canariensis Wild. (Canary Islands), and H. maderensis K. Koch ex A. Rutherford (Madeira). The Madeiran ivy has traditionally been related to the SW Iberian endemic H. iberica McAllister (Ackerfield & Wen). H. maderensis and H. iberica are quite different in leaf morphology but they are both hexaploids and have similar foliar trichomes. However, previous phylogenetic analyses based on Sanger sequencing failed to confirm a close relationship between them. Here we aim to 1) resolve the phylogenetic relationships of H. iberica and H. maderensis using genome-wide data generated by genotyping-by-sequencing (GBS), and 2) assess the role of climatic niche in their speciation using niche overlap analyses. Nine populations of H. iberica and seven of H. maderensis were used to prepare a GBS library. The tetraploid Hedera hibernica (G. Kirchner) Bean (12 localities) and the diploid Hedera helix L. (12 localities) were also included in the GBS library. Hedera hibernica was included because it is part of the Western polyploid clade of Hedera alongside our two study species, and H. helix because it has been related to the origin of the Western polyploid clade. Concatenation and coalescent-based phylogenies were constructed. Population genetic structure was studied through genetic principal components analysis (GPCA) and Bayesian analysis of population structure (BAPS). A geo-referenced database with 731 records of the four species was used to extract climatic data from the WorldClim database and perform niche overlap analyses. Hedera iberica and H. maderensis form a monophyletic group placed within a larger clade including most H. hibernica samples. Hedera iberica populations form a paraphyletic group, with the monophyletic H. maderensis nested within it as sister to a Portuguese population of H. iberica (Arrabida). Genetic structure analyses support H. iberica and H. maderensis as distinct genetic groups. Hedera iberica and H. maderensis exhibit narrower niches than H. helix and H. hibernica, and the niche of H. maderensis is included within the one of H. iberica. These results indicate that H. maderensis originated from H. iberica by progenitor-derivative speciation, and suggest that an ancestral “Macaronesian niche” was acquired by H. iberica in mainland Europe and may have facilitated the establishment of the ancestor of H. maderensis in the Macaronesian Island of Madeira.

1 - Universidad Autónoma de Madrid, Biology, C/ Darwin 2, 28049 Madrid, Spain, Madrid, Madrid, 28049, España
2 - Real Jardín Botánico (RJB-CSIC), C/Plaza de Murillo 2, 28014 Madrid, Spain, Madrid, Madrid, 28014, España

climatic niche.

Presentation Type: Poster
Session: P, Phylogenomics Posters
Location: Virtual/Virtual
Date: Wednesday, July 29th, 2020
Time: 5:00 PM Time and date to be determined
Number: PPL003
Abstract ID:405
Candidate for Awards:None

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