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Wasps have a pretty nasty reputation. When it comes to protecting their nests, they can be quite aggressive—which isn't really their fault.

They're just protecting their home and their families. But that's a whole different thing. See, as mean as these animals might appear, they're not always in anger mode.

In the fall, some species chill out and get together for what could only be called “wasp parties!” And much like our parties, these soirees can provide some fascinating insights into their social lives. People often report seeing large gatherings of paper wasps as summer slides into winter. But these aren't aggressive swarms.

Instead, the wasps just sort of seem to be hanging out. This lesser-known part of the wasps' life cycle is called pre-hibernation. See, wasp colonies pop up in the spring, each started by one or more females which are called foundresses.

By the summer, the colony is full of workers bustling about to take care of the eggs and babies that the foundresses produce. Then, as summer ends, the colony collapses. The sterile workers die.

The males mate with the remaining fertile females. And then, the males die, too. And these mated females—all potential queens called gynes—will spend the winter hibernating, waiting to start the whole yearly cycle over again when the flowers bloom.

But in some places, temperatures stay warm enough that they still have some time before they have to settle in. So, they gather in groups, especially near the tops of tall structures. No one's really sure what it is about tallness that they're attracted to, but they sure seem to like the roofs of silos or the tips of telephone poles.

Sometimes it's just a handful of wasps; and sometimes, it's hundreds. It's thought that these numbers might help keep them safe from predators and from the coming cold. And for decades, many entomologists assumed these gatherings were pretty boring.

But it turns out that much like human parties, there are some fascinating social dynamics going on. With no nests to defend, the wasps are pretty docile—not only toward intruders like us, but also towards each other. They'll chill alongside individuals from multiple colonies, and sometimes multiple species.

And even though they're all potential queens, a new social hierarchy forms. The wasps have been observed biting, lunging, and mounting each other, though no one gets badly hurt or kicked out of the group. They're just establishing who's in charge.

Some scientists have even characterized this behavior as playing. Much like puppies or kittens, these wasps may be play fighting, because in this low-stress environment, they can practice the skills they'll need to establish who's the boss in the spring. But that's not to say that there are no stakes in these games.

See, the females who lose these competitions act subordinate for the rest of the party, and some even fetch food for the group like workers in colonies usually do! And these social interactions seem to influence who wins in the long run. The lowest ranking wasps rarely survive the winter.

And the more dominant a wasp is during pre-hibernation, the more likely she is to become the dominant foundress of a colony in the spring. Entomologists have noted that the highest-ranking wasps at the parties show the traits that identify dominant foundresses, such as larger ovaries and a bigger body size. So, these chill gatherings may actually serve as early testing grounds where the wasps practice the social hierarchy that will benefit them later.

Far from being a boring time when the wasps are just waiting around, it may be that pre-hibernation is an essential step in preparing future foundresses for spring. So if you come across a swarm of laid-back wasps this fall, don't be a buzzkill. Leave them alone so they can ring in the winter their way.

Thanks for watching! If you want to learn more about wasps and why they're actually really awesome, you should check out our video on what would happen if we killed them all. And don't forget to subscribe! [OUTRO ♪].