Effect of food availability on larval cannibalism by foundresses of the paper wasp Polistes chinensis antennalis

Abstract

Cannibalism is a behavioral trait seen in a number of species and can be favored when the fitness gain outweighs the cost. In social wasps, field studies have suggested that food limitation causes larval cannibalism as a compensation of a meal for adult wasp and/or earlier production of the first workers, but experimental studies for the effect of food availability on larval cannibalism have been very scarce. Hence we examined whether Polistes chinensis antennalis foundresses exhibit a higher level of larval cannibalization under food-limited conditions than under food-available conditions. Larval cannibalization occurred frequently under both prey-and honey-limited conditions; however, young larvae were more frequently cannibalized than old larvae in the prey-limited colonies, while old larvae were more frequently cannibalized than young larvae in the honey-limited colonies. The number of days between colony initiation and the emergence of the first workers was not significantly different between the prey-limited and prey-available colonies, suggesting that under prey-limited conditions P. chinensis antennalis foundresses tend to cannibalize their young larvae and feed probably the flesh of these cannibalized larvae to old larvae in order to ensure the rapid production of the first workers. On the other hand, the number of days between colony initiation and the emergence of the first workers was longer in the honey-limited colonies than in the honey-available colonies. We propose explanations for the first time for why the foundresses in the honey-limited conditions cannibalized their old larvae more frequently than their young larvae in spite of this resulting in the delayed emergence of the first workers.

The Disappearance of Eggs and Larvae from the Nests of the Mischocyttarus (Monogynoecus) montei Zikán (Hymenoptera: Vespidae), Especially in Autumn and Winter: Can it Mean an Adaptive Cannibalism to Ensure the Survival of Colonies?

“…conditions; and 4 th -The similarity between our results under natural conditions and the results obtained by Mead et al (1994) and by Kudô and Shirai (2012) under manipulated conditions showed that it is possible to hypothesize the high disappearance of brood caused by scarce of food resource in adverse climatic conditions during the cold and dry period of the year. Thus, we believe that the cannibalism of small larvae, which occurred more frequently than cannibalism of medium and large larvae, represents an adaptive strategy of M. montei to ensure the development of the colony cycle, especially during unfavorable climatic conditions (during the autumn and winter).…”

“…Thus, adult wasps can feed larger larvae through the cannibalism of smaller larvae to obtain a faster production of adult individuals for colony. As observed by Kudô and Shirai (2012) in laboratorial conditions, the cannibalism occurred more frequently under prey-and honey-limited conditions. However, young larvae were cannibalized at high frequency under prey-limited conditions whereas old larvae under honey-limited colonies.…”

“…The following facts support the hypothesis of larval cannibalism as an adaptive strategy to overcome unfavorable climatic conditions: 1 st -Our hypothesis about the cannibalism of eggs and larvae to ensure the individual fitness is not considered here because the collection of data was made without the existence of conflict among females which can do the differential cannibalism (Pardi, 1948, West-Eberhard, 1969, Jeanne, 1972, Oliveira et al, 2012; 2 nd -The disappearance of eggs and larvae did not occur due to parasitoid attacks on the nests. This fact was observed in low frequencies (7 colonies from 41 studied colonies totalizing 1 egg, 6 larvae and 9 parasited pupae); 3 rdCannibalism in the social wasps was related under induced conditions with poor nutrition of adult individuals of the colony (Hunt, 1991), when the resource is limited (Mead et al, 1994;Kudô & Shirai, 2012) to observe the absolute frequency of the disappearance of eggs and larvae according to all months of the year. The frequency of disappearance of small larvae from the cells were higher (n= 128; 55,9 %) than medium larvae (n= 42; 18,3 %) and large larvae (n= 59; 25,8 %) (Table 3).…”

“…More recently, the relationship between availability of food and larval cannibalism of the foundress of P. chinensis antenalis was studied by Kudô and Shirai (2012), in laboratorial conditions. According to this study a higher frequency of cannibalism occurred under limited conditions of food, i.e., young larvae were cannibalized at higher frequency during limited conditions of prey whereas old larvae were cannibalized at higher frequency during limited conditions of honey.…”

“…In social wasps, studies have suggested that cannibalism on larvae is caused when food is scarce (Kudô & Shirai, 2012). Larval cannibalism of brood can be induced by poor nutrition of adult individuals in social wasps (Hunt, 1991).…”