Fascinating stuff, this human nature of the herd mentality. It's why cows grazing in a field are mostly facing in the same direction.
Actually ,it's have more to do with nature itself .
Cows can only see black & white , there for , the direction of the sun , and the shade , make them think the grass is bigger .
it's also have a lot to do with wind direction - many animals will face down wind , to avoid wind on the face .
that's why dogs with pointed ears ,will always face back , when riding on the back of a PU truck.
in cold Temp. it's help keeping buddy warm.
the wind also carry the Invader smell , so the animal can watch one way and smell the other way .
Moose.