Togetherness

I have featured this little herd of Irish Dexter cattle before. Their behaviour is really fascinating. Several times in the warmest parts of each day they all gather together in a tight little knot and stand swishing their tails vigorously, often heads-to-tails. This seems to be with the purpose of swishing flies off one another in a communal form of mutual back-scratching.
It is organised, purposeful and I think must involve some sort of communication or tacit agreement.
I do wonder how they make these decisions and how they communicate with one another.
The so called "herding instinct" is a well-known bovine characteristic, popularly believed to be protective - safety in numbers and a defence against predators being the purpose.
We don't have lions or hyenas hereabouts, but this little herd does keep together and appears to be very socially cohesive and mutually interested. I think that shared decision making may outrank instinct as an explanation.
There's a Ph.D in this for someone I am sure!
Like "people watching" cattle watching can be very satisfying.