It is relatively common knowledge that birds and mammals are capable of warning each other of danger. Alarm calling occurs readily in nature and is studied by many ethologists, however not much was known about alarm calling in insects. When attacked, pea aphids release an alarm pheromone called EBF to warn other aphids in the area of danger, as these aphids tend to be kin or mates alarm calling in aphids is a great example of increased inclusive fitness. Amount of EBF in aphids has also been linked to whether or not they grow up in groups–with solitary aphids producing drastically less EBF highlighting the connection between EBF, alarm-calling, and inclusive fitness benefits.
This research sought to explore whether there was specialization among aphids in response to different kinds of predators. To quantify different responses to different predators the researchers measured the amount of EBF emitted by pea aphids under attack from different species. These tiny green sap suckers demonstrated that by “marking” predators before their demise they increased the likelihood of survival for subsequent aphids attempting to be preyed upon.
The emission of EBF was found to be significantly different between attacks from lacewing flies vs ladybird beetles. However, attacks from lacewing flies were found to be longer than that of ladybird beetles which then corresponded with the varying levels of EBF emitted by the aphids (Lacewing attacks resulted in more EBF). Though the authors believe there is much more research to be done in this area, they felt comfortable concluding that like birds and mammals pea aphids are capable of producing varying degrees of predator alarm signaling. The notion of pea aphids producing varying levels of alarm signaling dependent on types of predator attack has implications for all other areas of the study of animal behavior and opens a pathway into further study into previously unstudied species and creates even more compelling opportunities in the field of entomology.
References
Joachim, C., Hatano, E., David, A., Kunert, M., Linse, C., & Weisser, W. (2013). Modulation of Aphid Alarm Pheromone Emission of Pea Aphid Prey by Predators. Journal Of Chemical Ecology, 39(6), 773. doi:10.1007/s10886-013-0288-x
Sarah Dickinson
November 7, 2017 — 7:03 pm
I don’t know if it would be considered a last ditch effort at some inclusive fitness or altruism that they mark predators for future aphids, but that’s still really cool!
Anner Harris
November 8, 2017 — 5:46 am
Wow, that’s really cool that aphids do this. I think there is definitely more room for research on insects and alarm calls.
Ishara Agostini
November 10, 2017 — 1:16 am
This is so exciting! there is so much communication between organisms happening beneath our very noses xD