title: Stimulating Anopheles gambiae swarms in the laboratory: application for behavioural and fitness studies.
abstract: BACKGROUND
  Male Anopheles mosquitoes that swarm rely in part on features of the environment including visual stimuli to locate swarms. Swarming is believed to be the primary behaviour during which mating occurs in the field, but is not a common behaviour in the laboratory. Features that stimulate male Anopheles gambiae G3 strain swarming were created in novel large indoor cages.
  
  
  METHODS
  The following visual features were tested in all combinations to determine which were important for swarm formation. Large cages and fading ceiling lights at dusk alone did not stimulate swarming while a dark foreground and contrasting illuminated background with a contrasting landmark stimulated and localized swarm formation during artificial twilight. Given the need to test transgenic strains in as natural a setting as possible, in this study it was investigated whether induced swarm behaviour and cage size would affect relative mating performance of wild-type and transgenic β2Ppo1 and β2Ppo2 A. gambiae sexually sterile males.
  
  
  RESULTS
  Even using a mosquito colony that has been in laboratory culture for 39 years, swarming behaviour was induced by this novel arrangement. The presence of swarming stimuli was associated with an increase in insemination frequency from 74.3 to 97.7% in large cages. Transgenic males showed a lower competitiveness in large cages compared to small cages regardless of the presence of swarming stimuli.
  
  
  CONCLUSIONS
  The results of the present study are discussed in view of the progressive evaluation of genetically modified A. gambiae strains and the potential applications of reproducing swarms in controlled conditions to dissect the mating behaviour of this species and the mechanisms controlling it.
authors.affiliation: Department of Experimental Medicine, University of Perugia, Perugia, Italy. lucafacchinelli@yahoo.it.
authors.forename: Luca
authors.initials: L
authors.lastname: Facchinelli
authors.affiliation: Department of Experimental Medicine, University of Perugia, Perugia, Italy. scarablaura@yahoo.it.
authors.forename: Laura
authors.initials: L
authors.lastname: Valerio
authors.affiliation: Department of Experimental Medicine, University of Perugia, Perugia, Italy. rosemarysusanlees@gmail.com.
authors.forename: Rosemary S
authors.initials: RS
authors.lastname: Lees
authors.affiliation: Department of Experimental Medicine, University of Perugia, Perugia, Italy. cleliaoliva@gmail.com.
authors.forename: Clelia F
authors.initials: CF
authors.lastname: Oliva
authors.affiliation: Department of Experimental Medicine, University of Perugia, Perugia, Italy. taniapersampieri@gmail.com.
authors.forename: Tania
authors.initials: T
authors.lastname: Persampieri
authors.affiliation: Centre for Environmental Policy, Imperial College London, London, UK. t.collins@imperial.ac.uk.
authors.forename: C Matilda
authors.initials: CM
authors.lastname: Collins
authors.affiliation: Department of Experimental Medicine, University of Perugia, Perugia, Italy. acrs@imperial.ac.uk.|Department of Life Sciences, Imperial College London, London, UK. acrs@imperial.ac.uk.
authors.forename: Andrea
authors.initials: A
authors.lastname: Crisanti
authors.affiliation: Department of Experimental Medicine, University of Perugia, Perugia, Italy. roberta.spaccapelo@unipg.it.
authors.forename: Roberta
authors.initials: R
authors.lastname: Spaccapelo
authors.affiliation: Department of Experimental Medicine, University of Perugia, Perugia, Italy. mqbenedict@yahoo.com.|Centers for Disease Control and Prevention, Atlanta, USA. mqbenedict@yahoo.com.
authors.forename: Mark Q
authors.initials: MQ
authors.lastname: Benedict
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified / Q000235:genetics / Q000502:physiology; D000852:Anopheles / Q000235:genetics / Q000502:physiology*; D003163:Competitive Behavior; D005260:Female; D007314:Insemination; D008297:Male; D009032:Mosquito Control / Q000379:methods*; D010775:Photic Stimulation / Q000379:methods*; D012726:Sexual Behavior, Animal