The ‘catapult’ or ‘butterfly’ body language is often displayed in project meetings.
Why is body language important to a project manager? Well, once you get past a certain level of experience in managing projects (or managing in general) you can concentrate on how to become even more effective. And one way of doing that is to improve communication, facilitation and collaboration skills. Watching and reacting to body lanuage helps with these activities enormously.
So what is the ‘catapult’ in a body language context? You will recognise it instantly. It is almost always done by men, very rarely women:
It is the placing of both hands (interlocked) behing the head or neck with elbows out. Usually the person is seated.
It occurs when the person is feeling superior (“untouchable” with confidence) on the subject under debate. Or just generally feeling in charge and superior to everyone else present.
Now that you know you can watch out for it and use it your advantage. You’ll find that often managers will display this body language in front of subordinates, but rarely does it occur the other way around. And if it does, there may be issues to explore and resolve there.

AFAIC that’s the best anwser so far!