Abstract Detail


Gallego-Narbón, Angélica [1], Alonso Hernandez, Alejandro [1], Valcarcel, Virginia [1], Fernandez-Mazuecos Santa Teresa, Mario [1].

Differential role of climatic niche in colonization and in-situ evolutionary processes of Macaronesian ivies (Hedera L., Araliaceae).

The genus Hedera L. (ivies) includes 12 vine species naturally distributed throughout Eurasia and northern Africa, including three single-species endemics in Macaronesian archipelagos: H. azorica Carrière (Azores), H. canariensis Wild (Canary Islands), and H. maderensis K. Koch ex A. Rutherford (Madeira). Previous studies using Sanger sequencing failed to resolve the phylogenetic relationships of these species but pointed to three independent origins. A recent study using the next-generation sequencing (NGS) technique genotyping by sequencing (GBS) revealed budding speciation of H. maderensis within the Iberian endemism H. iberica (McAll.) Ackerf. & J.Wen and the influence of climatic niche pre-adaptation in the successful colonization of Madeira [1]. Here we aim to 1) clarify the phylogenetic placement of the Macaronesian species H. azorica and H. canariensis using the GBS technique and 2) assess the role of climatic niche and geographic barriers in the colonization and diversification processes of Hedera in the Macaronesian archipelagos of Azores, Canary Islands and Madeira. In this study, we included 167 samples (85 were newly sequenced) from 100 populations representing the genus Hedera. We included samples from 33 populations of Macaronesian ivies (12 of H. azorica, 11 of H. canariensis and 10 of H. maderensis), 10 populations of North African species (2 of H. algeriensis Rantonnet ex C.Morren and 8 of H. maroccana McAll.), and 40 populations of mainland European ivies (20 of H. helix L., 12 of H. hibernica (G. Kirchner) Bean and 8 of H. iberica). Additionally, we completed the sampling with 13 Asian samples representing the remaining species of Hedera and 4 Araliaceae samples of other genera as the outgroup. Concatenation and coalescent-based phylogenies were estimated. Biogeographic analyses were implemented on the time-calibrated phylogeny. Climatic preferences and niche evolution were assessed from a geo-referenced database with 2,297 records of the western ivy species. The GBS phylogeny revealed an early split between a Western clade and an Asian clade. Hedera canariensis diverged early as sister to the remaining Western clade (7.5-12 Ma), while H. azorica and H. maderensis show a recent divergence closely related to H. helix (4.4-6.8 Ma) and H. iberica (2.8-4.6 Ma), respectively. Biogeographic reconstructions suggest a western Mediterranean origin of the Macaronesian species and confirm three independent colonization events, one per archipelago. Macaronesian species occupy a climatic niche well differentiated from that of the western continental species (Macaronesian ivy niche) and had different climatic affinities. These results indicate that climatic niche has evolved differently for each Macaronesian species, as H. maderensis and H. canariensis had mainland ancestors with a similar climatic affinity while the climatic niche of H. azorica has strongly differentiated from that of its ancestor. Despite the differential role of climatic preferences in the colonization processes of the three Macaronesian archipelagos, the acquisition of Macaronesian niches in ivies seems to have played a similar role in the three archipelagos, leading to a process of speciation with no further in-situ diversification.
[1] Alonso et al. (2021). bioRxiv. DOI:10.1101/2021.07.16.452604

1 - Universidad Autónoma de Madrid, Department of Biology, Campus de Cantoblanco, C/ Darwin 2, Madrid, 28049, Spain

Climatic niche

Presentation Type: Oral Paper
Number: PHYLO I007
Abstract ID:100
Candidate for Awards:None

Copyright © 2000-2022, Botanical Society of America. All rights reserved