Although you won’t be seeing many of these pests now that the winter months have set in, it is interesting to know that humans are most definitely NOT the only species addicted to the stimulatory chemical caffeine!
Wasps go crazy for caffeine, so all that time you were being harassed by wasps for a drop of your fizzy, sugary drink, you might not have had quite so much attention should you have gone for the caffeine free alternative. Nature is responsible for this buzz surrounding caffeine, this is because the nectar from some flowers contains low levels of caffeine, meaning those waspy little fellas become frenzied when a nice, sweet fizzy beverage contains a good helping of caffeine too.
Ishay, J, S., and Paniry, V, A, (2014). Effects of caffeine and various xanthines on hornets and bees. Retrieved 8th December, 2014, from http://www.ncbi.nlm.nih.gov/pubmed/117503