Over the centuries, we believed that animals do not have an intelligence or the ability of logical thinking and learning.It was believed that their lives are just guided by "Instinct". However as expected there is no consensus about this among scientists due to the difficulty in designing the experiments which can be used generally to assess the intelligence among various species making the interpretation very difficult.

One can argue that if animals like horses, dogs or dolphins are really intelligent, then why they loose their freedom to us and become our pet but other side of the argument can be they get food and protection as pets which they wont get in the wild.

Every organism has some kind of blue print which it knows since birth and other information for survival is gained by experience either of their own and learnt from those of parents and relatives. Nature has given each and every animal some kind of power necessary for survival.

We all have heard the story of Abhimanyu who learnt the art of breaking into "Chakravyuh" while in Subhadra's womb and modern science also confirms that human babies along with other mammals have womb with a view, i.e. a sound view and babies of humans as well as other animals can recognize their mother's voice and can differentiate that with other sounds and also respond to the various events experienced by their mother. This ability is especially vital for survival in the wild for animals especially located at bottom or middle of the food-chain. e.g  mallard ducklings cant survive without their mother and start following their mother everywhere immediately after they hatch. The experiments showed that the ducklings followed a box containing recorded sound of their mother instead of another duck, which shows that the mother's sound is more important than her appearance which is understandable in the night where the vision would be limited.This certainly doesnt mean that they cant differentiate between shapes or so,but the sound is just more important for their initial survival.

Similar thing happens in a Ring-billed gull colony...In a single colony, there would be thousands of birds and sound is the only effective way to avoid getting lost and get attention of parents to get food as their would be thousands of hatching at same time. To confirm this, some experiments were carried on these species in which one clutch of eggs was exposed to maternal feeding call sounds while another clutch was incubated in silence. After hatching the chicks which have heard their mother's calls while in eggs, pecked at her beak encouraging her to regurgitate the food while the other group didnt peck at their mother at all and certainly had little chance of survival in the wild. These birds are extremely territorial and a chick lost from its parents would certainly be killed by other gulls. Hence the hearing mother's call while in egg, also has a survival value.