Fossog B. T. auteur aut IRD Ayala Diego auteur aut IRD Acevedo P. auteur aut IRD Kengne Pierre auteur aut IRD Mebuy I. N. A. auteur aut IRD Makanga B. auteur aut IRD Magnus J. auteur aut IRD Awono-Ambene P. auteur aut IRD Njiokou F. auteur aut IRD Pombi M. auteur aut IRD Antonio-Nkondjio C. auteur aut IRD Paupy Christophe auteur aut IRD Besansky N. J. auteur aut IRD Costantini Carlo auteur aut IRD text journalArticle eng text/pdf born digital access Understanding how divergent selection generates adaptive phenotypic and population diversification provides a mechanistic explanation of speciation in recently separated species pairs. Towards this goal, we sought ecological gradients of divergence between the cryptic malaria vectors Anopheles coluzzii and An.gambiae and then looked for a physiological trait that may underlie such divergence. Using a large set of occurrence records and eco-geographic information, we built a distribution model to predict the predominance of the two species across their range of sympatry. Our model predicts two novel gradients along which the species segregate: distance from the coastline and altitude. Anopheles coluzzii showed a bimodal' distribution, predominating in xeric West African savannas and along the western coastal fringe of Africa. To test whether differences in salinity tolerance underlie this habitat segregation, we assessed the acute dose-mortality response to salinity of thirty-two larval populations from Central Africa. In agreement with its coastal predominance, Anopheles coluzzii was overall more tolerant than An.gambiae. Salinity tolerance of both species, however, converged in urban localities, presumably reflecting an adaptive response to osmotic stress from anthropogenic pollutants. When comparing degree of tolerance in conjunction with levels of syntopy, we found evidence of character displacement in this trait. specialized Anopheles coluzzii Anopheles gambiae cryptic species ecological character displacement ecological speciation habitat segregation malaria vector molecular forms niche partitioning saltwater tolerance spatial ecology species distribution modelling urban pollution CAMEROUN GUINEE EQUATORIALE GABON AFRIQUE DE L'OUEST AFRIQUE CENTRALE 052 082 8 4 326-345 2015 1752-4571 https://www.documentation.ird.fr/hor/fdi:010064159 10.1111/eva.12242 1752-4571 [F B010064159] https://www.documentation.ird.fr/hor/fdi:010064159 https://www.documentation.ird.fr/intranet/publi/2015/05/010064159.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2015-06-04 2021-05-20 fdi:010064159 fre