Holocene climate change promoted allopatric divergence and explains the current disjunct geographic distribution of the Ophrys aveyronensis species complex (Orchidaceae)

Anaïs Gibert; Roselyne Buscail; Michel Baguette; Christelle Fraïsse; Camille Roux; Bertrand Schatz; Joris a M Bertrand

doi:10.1101/2023.04.27.538532

Holocene climate change promoted allopatric divergence and explains the current disjunct geographic distribution of the Ophrys aveyronensis species complex (Orchidaceae)

Anaïs Gibert, Roselyne Buscail, Michel Baguette, Christelle Fraïsse, Camille Roux, Bertrand Schatz Joris a M Bertrand

29/04/2023

: https://doi.org/10.1101/2023.04.27.538532

Abstract Species with disjunct geographic distributions provide natural opportunities to investigate recent or incipient allopatric divergence. Although not rare, many of the cases observed result from successful colonization from a historical to a new range through dispersal or human-induced introduction which make the underlying eco-evolutionary processes sometimes difficult to decipher. The Ophrys aveyronensis species complex presents a disjunct geographic distribution with two ranges currently separated by 600 km on both sides of the Pyrenees Mountains. To uncover the causes of such intriguing biogeographic pattern, we combined population genomics and Ecological Niche Modelling approaches. Population genomic data show that all the populations studied display similar patterns of genetic diversity and dramatic decrease in effective size. We found significant genetic differentiation between the two ranges of the O. aveyronensis species complex. Our results support a very recent divergence ( ca. 1500 generations ago). Ecological Niche Modelling results further indicate that the disjunct geographic distribution of the O. aveyronensis species complex is consistent with a range split of a broad ancestral range, contraction and shifts in opposite directions in response to climate warming during the Holocene. The congruence of both the results of population genomics and ENM approaches demonstrates that continental allopatric divergence is involved in the Ophrys adaptive radiation. The O. aveyronensis complex is a promising candidate to study the onset of reproductive isolation immediately following an initial stage of geographic separation.

(1)

url

Find in HAL

: Holocene climate change promoted allopatric divergence and explains the current disjunct geographic distribution of the Ophrys aveyronensis species complex (Orchidaceae)
: Anaïs Gibert - Laboratoire Génome et Développement des Plantes
Roselyne Buscail - Centre de Formation et de Recherche sur les Environnements Méditerranéens
Michel Baguette - École Pratique des Hautes Études
Christelle Fraïsse - Unité Évolution, Écologie et Paléontologie
Camille Roux - Unité Évolution, Écologie et Paléontologie
Bertrand Schatz - Centre d'Écologie Fonctionnelle et Évolutive
Joris a M Bertrand - Laboratoire Génome et Développement des Plantes
: 9935449509311
: Institut des Sciences de l'Evolution - Montpellier - ISEM
: English
: Working paper
: hal-04310388