Just had this thought today---two of my young chickens and two of my old ones are RIR and they look exactly alike. So how do the other old hens know to chase the young ones out of the coop and leave their (same age) sisters/friends alone? Do they make some noise or can they smell each other? Is it high frequency that we can't hear? This fascinated me in "March of the Penguins" where each bird knew his/her mate and chick in the middle of 100,000 others who looked the same and sounded the same (to me). Maybe I need to get out more........
My guess would be that the chickens don't look the same, at least not to the other chickens. I don't think chickens can smell, so it couldn't be that. It's probably to do with the way the chickens act too. Or how they sound.
I was curious about a similar phenomenon I noticed when I first received my chickies. They would all bundle together by breed... But how do they know what they look like? Chickens are a strange sort...
I think it is an energy thing. Kind of like how dogs feed off each others energy, or how we get 'gut feelings' about people we just met or that sort of thing. I say this because it seems that in a peaceful flock you can take out a hen or two and then a week later put them back and it is like adding two new chickens. So, they don't 'recognize' them in a typical way like people or other animals do. So, different breeds must have different energies and when your chicks grow up together they tend to stay together because they feel secure in their group of familiar energies.
They are bonded like mothers to baby in the hospital. Regular people can't tell one from another but momma can find her baby right off. I guess that's why broodies are so mean, they keep everyone away until she can tell HER chicks from the others'
