This July 2018 video shows two common carder bees mating.
Anja Barendrecht in the Netherlands made this video.
The Brazilian stingless bee Tetragonisca angustula (jataí in Portuguese) deploys a different strategy for defending its nests from other social insect species. In addition to posting sentinels at the nest entrance, as do most social insects, colonies of this species also have guards that hover near the entrance all the time: here.
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