Studies of predator–prey interactions leading to NFDS have focused almost exclusively on the effect that predators have on prey populations (see earlier). The possibility of prey affecting the frequencies of morphs in predator populations has received far less consideration. If a predator’s main prey can discriminate between predator morphs, it might learn to avoid the predator morph that it encounters more frequently by associating it with a potential attack. Predators of the morph that is avoided by prey are expected to catch fewer prey and feed less often, which will learn more affect their fitness and cause their frequency to decrease relative to rare

morphs that are not as easily recognized by the prey. SP600125 order Such frequency dependence could maintain a balanced polymorphism in exactly the same way as was originally predicted when predators forage preferentially for common prey morphs. Evidence for NFDS on predator morphs by prey is scant (Hori, 1993), but there is clear potential

in some systems. For example, some spiders show conspicuous variation in body colour and pattern (Théry & Casas, 2009), and attack prey, such as bees, which are known to be able to discriminate colours (Giurfa, 2004; Dyer & Neumeyer, 2005; Srinivasan, 2010; Dyer, Paulk & Reser, 2011). Studies have shown that spider colouration affects the behaviour of some prey species in such a way that spider

fitness is likely to be affected (Hauber, 2002; Tso, Lin & Yang, 2004; Heiling et al., 2005; Tso et al., 2006; Ings & Chittka, 2008; Herberstein, Heiling & Cheng, 2009; Llandres et al., 2011). Most studies that have investigated colour variation in spiders have concentrated on species with forms that choose their backgrounds in relation to their colour, and use colouration to appear cryptic or to attract prey (Théry & Casas, 2002; Heiling, Herberstein & Chittka, 2003; Heiling et al., 2005; Defrize, Théry & Casas, 2010). However, we have found evidence selleck chemicals llc in favour of prey avoiding recently encountered colour morphs of the crab spider, Synema globosum (H. Ajuria-Ibarra & T. Reader, unpubl. data). This species shows a female-limited colour polymorphism, where females can have red, yellow or white colouration on their abdomen (Roberts, 1995). Synema globosum’s main prey are honeybees (Apis mellifera), and the spiders appear to choose flowers independently of their colour. We observed that after previously experiencing a simulated attack while visiting a flower harbouring a spider of one morph, honeybees were significantly less likely to visit a flower with a spider of the same morph a second time, whereas no such effect was found if the second flower harboured a spider of a different morph.