Habitat segregation and ecological character displacement in cryptic African malaria mosquitoes

Evolutionary Applications

Billy Tene Fossog⁷  Diego Ayala⁷  Pelayo Acevedo⁸  Pierre Kengne⁷  Ignacio Ngomo Abeso Mebuy¹  Boris Makanga⁷  Julie Magnus⁴  Parfait Awono-Ambene²  Flobert Njiokou⁵  Marco Pombi⁶  Christophe Antonio-Nkondjio²  Christophe Paupy⁷  Nora J. Besansky³ 

[1] Faculty of Medicine, Universidad Nacional de Guinea Ecuatorial (UNGE), Bata, Equatorial Guinea;Laboratoire de Recherche sur le Paludisme, Organisation de Coordination pour la lutte contre les Endémies en Afrique Centrale (OCEAC), Yaoundé, Cameroon;Eck Institute for Global Health & Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, USA;Centre International de Recherches Médicales de Franceville (CIRMF), Franceville, Gabon;Department of Animal Biology, Faculty of Sciences, University of Yaoundé I, Yaoundé, Cameroon;Sezione di Parassitologia, Dipartimento di Sanità Pubblica e Malattie Infettive, Università di Roma ‘La Sapienza’, Rome, Italy;Institut de Recherche pour le Développement (IRD), UMR MIVEGEC (UM1, UM2, CNRS 5290, IRD 224), Montpellier, France;SaBio, Instituto de Investigación en Recursos Cinegéticos (IREC), CSIC-UCLM-JCCM, Ciudad Real, Spain

关键词: 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;   

DOI  :  10.1111/eva.12242

来源: Wiley

【 摘 要 】

Abstract

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.

【 授权许可】

CC BY   
© 2014 The Authors. Evolutionary Applications published by John Wiley & Sons Ltd

Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.