This is a question that is going to really brand me a city girl, I'm afraid!

A friend and I were out driving this weekend to find wildflowers. This is the perfect time for them to be blooming.

Every time we saw cows, they were all together. It didn't matter how big the field was, they were always in a group. My friend said that's just what cows do. Why? Why don't they spread out?

My friend also said that that's why you can put a cowbell on just one cow - the "lead cow" - if you lead her home, the rest of them will follow. Again, why?! And, how do you find out who she is (walk into the group and say, "Ok! Who's in charge here? Raise your hoof." )?!

The horses don't do it. The donkeys we saw weren't doing it. The goats kinda were, but not to the extent that the cows were.

I need to know! This was a very intriguing mystery this weekend!

They stick together for safety. Herd animals. It would be impossible to herd cattle and sheep if they didn't stick together. On the open range they do separate for forage and to have their calves. Ranchers have to go looking for individuals in gullys and surrounding hills.
As far as finding the lead cow, it's done by observation. Cows use the same path from water to forage and will walk single-file from the stock water tank back to grazing. When it's time to leave one location the lead cow takes over. I've never seen a belled animal in Wyoming but in dairy cow herds I think that the bell is an aid to the rancher so he can hear where the herd may be without looking too far.