Parental phenotype not predator cues influence egg warning coloration and defence levels (article)
© 2018 The Authors. Published by Elsevier Ltd on behalf of The Association for the Study of Animal Behaviour. Open Access funded by Natural Environment Research Council. Under a Creative Commons license: https://creativecommons.org/licenses/by/4.0/
In species that advertise their toxicity to predators through visual signals, there is considerable variation among individuals in both signal appearance and levels of defence. Parental effects, a type of non-genetic inheritance, may play a key role in creating and maintaining this within-species diversity in aposematic signals, however a comprehensive test of this notion is lacking. Using the ladybird Adalia bipunctata we assess how egg coloration and defence level (concentration of the toxic alkaloid (-)-adaline) is influenced both by simulated predation risk in the egg laying environment, and by parental phenotype (coloration and toxin level). We found that egg toxin level and colour were predicted by parental phenotype, but were not altered in response to cues of egg predators. Egg luminance (lightness) was positively correlated with paternal elytral luminance, whilst maternal toxin level positively predicted egg toxin level. In response to egg predator cues, ladybird mothers altered the timing of laying and total egg number, but not egg toxin level or colour. It appears therefore that in A. bipunctata variation between individuals of the same morph in the colour and toxin level of the eggs they lay, i.e. egg aposematic phenotype, is more strongly influenced by individual variation in parental aposematic traits than environmental cues of egg predation risk. Furthermore, these results provide the first indication that, in a warningly coloured species, male coloration may play a dual role as predator deterrent and indicator of paternal quality, influencing maternal investment in offspring.
This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record
The dataset associated with this article is located in ORE at: http://hdl.handle.net/10871/32137
Vol. 140, pp. 177-186
Except where otherwise noted, this item's license is described as © 2018 The Authors. Published by Elsevier Ltd on behalf of The Association for the Study of Animal Behaviour. Open Access funded by Natural Environment Research Council. Under a Creative Commons license: https://creativecommons.org/licenses/by/4.0/