Meeting Abstract

57.3  Saturday, Jan. 5  Maternal predation risk induces transgenerational behavioral plasticity in a parthenogenetic insect KEISER, C.N.*; MONDOR, E.B.; University of Pittsburgh, PA. Georgia Southern University, Statesboro, GA; Georgia Southern University, Statesboro, GA

It is becoming increasingly evident in many organisms that cues of immediate and latent predation risk in one generation can induce defensive phenotypes in the next generation. This predator-induced transgenerational phenotypic plasticity has been widely documented in the induction of defensive morphologies in naïve offspring, though relatively little is known about transgenerational plasticity in offspring behavior. To address the possibility of transgenerational behavioral plasticity in the pea aphid, Acyrthosiphon pisum, a group-feeding parthenogenetic insect, we exposed pre-reproductive individuals of two clonal lines (“green” and “pink” color morphs) to the aphid alarm pheromone (E)-&beta-Farnesene (EBF), a reliable cue of increased predation risk. Compared to controls groups, offspring of aphids exposed to a single alarm pheromone emission altered their feeding site choices relative to the location of the maternal aphids, occupying lower-risk feeding sites. The two clonal lines responded differently; green juveniles occupied “safer” feeding sites in the natal colony, while pink offspring were more likely to disperse to feeding sites on neighboring plant leaves. Offspring responses were also different depending on the cultivar of broad bean, Vicia faba, upon which they were feeding. This may indicate an influence of host-plant quality on aphid defensive behavior. Further studies are needed to clarify the association between the transgenerational induction of morphological and behavioral defenses, and how transgenerational behavioral plasticity augments survival of the clonal lineage.