18Cannibalism has been reported in a large proportion of coccinellids in fields as well as in 19 laboratories but studies involving mate preferences and potential benefits of cannibalism on 20 reproduction in Menochilus sexmaculatus Fabricius (Coleoptera: Coccinellidae)have yet not 21 been done. Thus, we assessed the effect of conspecific egg cannibalism on mate preferences 22 and reproductive outputs including offspring development. Higher mate preferences were 23 recorded for non-cannibal mates (fed on A. craccivora) than cannibal ones (fed on conspecific 24 eggs). Mating parameters significantly influenced by cannibalism. Time to commence mating 25 lasted less for homogeneous diet pairs than heterogeneous diet pairs. Longer copulation 26 duration and higher fecundity were recorded when one of the individuals in mating pair or both 27 was a non-cannibal. Egg viability did not differed significantly in all reciprocal crosses. Total 28 developmental durations of offspring were similar for all mating pairs. 29 Keywords: aphids, cannibal and non-cannibal, fecundity, egg viability, development. 30 31 109 simultaneous choice of males from both dietary regimes. Each mate preference treatment was 110 replicated 20 times. 111 The mating parameters, viz. time of commencement of mating and copulation durations of each 112 pair were recorded. In order to assess the effect of cannibalism on reproductive performance, 113 the following combinations obtained from both the female and male mate preference setup 114 were observed, Fnc × Mnc, Fnc × Mc, Fc × Mnc, Fc × Mc (F and M representing female and male 115 respectively; 'nc' and 'c' representing non-cannibal and cannibal, respectively).
116After the termination of mating, the male was removed and the females were maintained on 117 their pre-assigned diet. Daily oviposition and hatching were recorded for the next 5 days 118 Statistical analysis 119 The chi-square (χ2) goodness-of-fit analysis was used to test the null hypothesis of random 120 mating. Data on mating and reproductive outputs, i.e. time of commencement of mating, 121 copulation duration, fecundity, egg viability, and developmental durations were first tested for 122 normality (Kolmogorov-Smirnoff). On being found normally distributed, each of the previous 123 measurements was subjected to one-way analysis of variance (ANOVA) with diet as 124 independent factors. The analysis was followed by the comparison of means using post hoc 125 235 Avent, T.D., Price, T.A.R., Wedell, N., 2008. Age-based female preference in the fruit fly 236 Drosophila pseudoobscura. Anim.