I WONDER - Can Chickens Recognise Their Chicks?

Mother chickens exhibit a physical response, such as increased heart rate, when their chicks are in distress. They possess the ability to recognize not only each other but also humans. Additionally, chickens can form social bonds, allowing them to remember up to 100 individual faces.

What happens to the heart rate of mother chickens when their chicks are in distress?

How many individual faces can mother chickens recognize?