ropean hornets (Vespa crabro) and wasps such as the common wasp (Vespula vulgaris) or the German wasp (Vespula germanica) can often be observed at feeding sites such as fruit trees or sugary foods.

A high school teacher trying to solve the mystery of why queen Vespula wasps mate with many different males thinks the practice might have evolved to stave off a catastrophic colony collapse.