Explaining how and why reproductive isolation evolves and determining which forms of reproductive isolation have the largest impact on the process of population divergence are major goals in the study of speciation. By studying recent adaptive radiations in incompletely isolated taxa, it is possible to identify barriers involved at early divergence before other confounding barriers emerge after speciation is complete. Sibling species of the Anopheles gambiae complex offer opportunities to provide insights into speciation mechanisms. Here, we studied patterns of reproductive isolation among three taxa, Anopheles coluzzii, An. gambiae s.s. and Anopheles arabiensis, to compare its strength at different spatial scales, to dissect the relative contribution of pre-versus postmating isolation, and to infer the involvement of ecological divergence on hybridization. Because F1 hybrids are viable, fertile and not uncommon, understanding the dynamics of hybridization in this trio of major malaria vectors has important implications for how adaptations arise and spread across the group, and in planning studies of the safety and efficacy of gene drive as a means of malaria control. We first performed a systematic review and meta-analysis of published surveys reporting on hybrid prevalence, showing strong reproductive isolation at a continental scale despite geographically restricted exceptions. Second, we exploited our own extensive field data sets collected at a regional scale in two contrasting environmental settings, to assess: (i) levels of premating isolation; (ii) spatio/temporal and frequency-dependent dynamics of hybridization, (iii) relationship between reproductive isolation and ecological divergence and (iv) hybrid viability penalty. Results are in accordance with ecological speciation theory predicting a positive association between the strength of reproductive isolation and degree of ecological divergence, and indicate that postmating isolation does contribute to reproductive isolation among these species. Specifically, only postmating isolation was positively associated with ecological divergence, whereas premating isolation was correlated with phylogenetic distance.

Dissecting functional components of reproductive isolation among closely related sympatric species of the Anopheles gambiae complex / Pombi, Marco; Kengne, Pierre; Gimonneau, Geoffrey; Tene-Fossog, Billy; Ayala, Diego; Kamdem, Colince; Santolamazza, Federica; Guelbeogo, Wamdaogo Moussa; Sagnon, N'Falé; Petrarca, Vincenzo; Fontenille, Didier; Besansky, Nora Jessie; Antonio-Nkondjio, Christophe; Dabiré, Roch Kounbobr; Della Torre, Alessandra; Simard, Frederic; Costantini, Carlo. - In: EVOLUTIONARY APPLICATIONS. - ISSN 1752-4571. - ELETTRONICO. - 10:10(2017), pp. 1102-1120. [10.1111/eva.12517]

Dissecting functional components of reproductive isolation among closely related sympatric species of the Anopheles gambiae complex

Pombi, Marco
Conceptualization
;
Santolamazza, Federica
Methodology
;
Petrarca, Vincenzo
Supervision
;
Besansky, Nora Jessie;Della Torre, Alessandra
Writing – Original Draft Preparation
;
SIMARD, FREDERIC;
2017

Abstract

Explaining how and why reproductive isolation evolves and determining which forms of reproductive isolation have the largest impact on the process of population divergence are major goals in the study of speciation. By studying recent adaptive radiations in incompletely isolated taxa, it is possible to identify barriers involved at early divergence before other confounding barriers emerge after speciation is complete. Sibling species of the Anopheles gambiae complex offer opportunities to provide insights into speciation mechanisms. Here, we studied patterns of reproductive isolation among three taxa, Anopheles coluzzii, An. gambiae s.s. and Anopheles arabiensis, to compare its strength at different spatial scales, to dissect the relative contribution of pre-versus postmating isolation, and to infer the involvement of ecological divergence on hybridization. Because F1 hybrids are viable, fertile and not uncommon, understanding the dynamics of hybridization in this trio of major malaria vectors has important implications for how adaptations arise and spread across the group, and in planning studies of the safety and efficacy of gene drive as a means of malaria control. We first performed a systematic review and meta-analysis of published surveys reporting on hybrid prevalence, showing strong reproductive isolation at a continental scale despite geographically restricted exceptions. Second, we exploited our own extensive field data sets collected at a regional scale in two contrasting environmental settings, to assess: (i) levels of premating isolation; (ii) spatio/temporal and frequency-dependent dynamics of hybridization, (iii) relationship between reproductive isolation and ecological divergence and (iv) hybrid viability penalty. Results are in accordance with ecological speciation theory predicting a positive association between the strength of reproductive isolation and degree of ecological divergence, and indicate that postmating isolation does contribute to reproductive isolation among these species. Specifically, only postmating isolation was positively associated with ecological divergence, whereas premating isolation was correlated with phylogenetic distance.
2017
ecological speciation; hybridization; postmating; premating; reproductive isolation; species complex; ecology, evolution, behavior and systematics; genetics
01 Pubblicazione su rivista::01a Articolo in rivista
Dissecting functional components of reproductive isolation among closely related sympatric species of the Anopheles gambiae complex / Pombi, Marco; Kengne, Pierre; Gimonneau, Geoffrey; Tene-Fossog, Billy; Ayala, Diego; Kamdem, Colince; Santolamazza, Federica; Guelbeogo, Wamdaogo Moussa; Sagnon, N'Falé; Petrarca, Vincenzo; Fontenille, Didier; Besansky, Nora Jessie; Antonio-Nkondjio, Christophe; Dabiré, Roch Kounbobr; Della Torre, Alessandra; Simard, Frederic; Costantini, Carlo. - In: EVOLUTIONARY APPLICATIONS. - ISSN 1752-4571. - ELETTRONICO. - 10:10(2017), pp. 1102-1120. [10.1111/eva.12517]
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11573/1072744
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