I think that the chickens do learn their 'language' and also some behaviour. I have seen the young chicks watch and copy the adults. Yes they have instincts and pre programmed behaviours, but they learn to modify them for their environment and their flock.
For example, I see with my chickens that the young pick up the 'language' for different predators from the older birds. They all will have a basic innate noise and responds for predators, but each flock has a slightly different call and behaviour. If I put a bird form another place in with my ones I notice it does not always respond the same way as my other birds to their calls. But after a week of 2 it will know what each noise means - like I got mealworm treats, or someone one new is in the garden etc.
Bird do learn song, and calls from their parents, that why the same species can have slightly different songs depending on the region or country it comes from. I breed Zebra doves for their calls. In Thailand we have dove cooing competitions with high prize money. There are many dove farms breeding different classes of singer. The chicks learn the calls form their parents as they grow up. So now the best ones sound very different to the wild ones.
For example, I see with my chickens that the young pick up the 'language' for different predators from the older birds. They all will have a basic innate noise and responds for predators, but each flock has a slightly different call and behaviour. If I put a bird form another place in with my ones I notice it does not always respond the same way as my other birds to their calls. But after a week of 2 it will know what each noise means - like I got mealworm treats, or someone one new is in the garden etc.
Bird do learn song, and calls from their parents, that why the same species can have slightly different songs depending on the region or country it comes from. I breed Zebra doves for their calls. In Thailand we have dove cooing competitions with high prize money. There are many dove farms breeding different classes of singer. The chicks learn the calls form their parents as they grow up. So now the best ones sound very different to the wild ones.