Availability of unfertilised eggs increases the fitness of nymphal crickets (Gryllidae)

Abstract

1. Female insects of many species lay both fertilised and unfertilised eggs, with the latter accounting for up to 50% of the total number laid. These unfertilised eggs do not hatch and so their relevance is unclear.2. In the present study, it was found that nymphs of the cricket Velarifictorus aspersus ate unfertilised eggs regardless of whether there was other food available. This provision enabled nymphs to develop successfully when no other food was provided, and to gain additional body mass when other food was available under crowded conditions. These results suggest that unfertilised eggs have an important role in the survival and development of nymphs.3. Nymphs preferred to eat unfertilised rather than fertilised eggs, suggesting that they may have the ability to distinguish between these two types of eggs.4. Crowding promoted feeding on unfertilised eggs and accelerate nymphal development, suggesting that greater food consumption accounts for faster growth under grouped conditions.

Love them all: mothers provide care to foreign eggs in the European earwig Forficula auricularia

“…This phenomenon has been reported in several earwig species, including F. auricularia (Miller and Zink 2012;Koch and Meunier 2014). Filial egg cannibalism is generally considered as an adaptive process if it either (i) targets damaged, parasitized or diseased eggs, (ii) reduces the future level of sibling competition for limited resources, (iii) allows parents to re-allocate their resources into future reproduction after a sudden deterioration in their environmental conditions or (iv) if it targets unfertilized trophic eggs and is used as a regular food source to parents when other food sources are scarce (Bartlett 1987;Crespi 1992;Lindström and Sargent 1997;Thomas and Manica 2003;Lourdais et al 2005;Klug et al 2006;Miller and Zink 2012;Zeng et al 2017). This fourth hypothesis could operate in earwigs, as mothers constantly remain in their nest over the period of egg care (Kölliker 2007) which largely occurs during the period when food sources are typically very limited (Lamb 1976).…”

Fight outcome briefly affects the reproductive fitness of male crickets

“…Previous study has shown that this species is polygamous and that multiple copulation increases the fertilization success of females 39 . Therefore, we examined the effects of dominance on the fecundity and fertilization success of females when mated two or three times.…”

Reproductive Strategies in Insects

“…The consumption of fertile eggs has been reported in several insect species (Frechette and Coderre, 2000;López-Ortega and Williams, 2018), making it difficult to understand what is the main driver of egg cannibalism. In other species such as in the cricket Velarifictorus asperses, however, nymphs have been shown to discriminate between fertile and non-fertile eggs and to selectively consume the latter (Zeng et al, 2017).…”