The house has 4 children, but 3 of them are different.

The house has 4 children, but 3 of them are different.
The mother starling has hatched 4 chicks, but there is something off here. There is one chick with a yellow beak, while the other 3 chicks have red beaks. So, who is the biological child of the yellow-beaked mother? In the bird world, there is a species called the cuckoo, which specializes in laying its eggs in the nests of other birds so it doesn't have to raise its young. Let's investigate which chick is the biological one.