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Full list of author information is available at the end of the articleFlying and biting arthropods are economically and epide-miologically important as agricultural pests and medical and veterinary vectors of disease, with over 3.2 billion people threatened by malaria and more than 5 billion people at risk from arboviruses (e.g. dengue fever) [1]. Most of these insects, such as mosquitoes, tsetse flies and moths, rely on olfactory cues for many essential life and breeding sites, while repellent odours include plant defensive toxins and predatory signals that deter ovipos-ition [2-4]. An insect’s responsiveness to host-emitted odours will affect its reproductive success and life-history, which in turn will determine its evolutionary fitness. A vector’s feeding success is also a strong determinant of the epidemiology and transmission of infectious diseases [5]. For example, anopheline mosquito species in sub-Saharan Africa such as Anopheles gambiae sensu stricto (s.s.) are some of the most efficient vectors of human malaria, pre