what happened to these animals (dogs ) to make them like this and is there any other animal that shows its love for humans in this way ?

it is in their nature.. you are nice to them and they will always be faithfufl.. they are dogs. enjoy it

I'd say that most likely dogs are just like that, they like attention, they like to learn, and they like people. Man probably learned this about dogs over the course of time, and today, lots of breeds have become domesticated to more fit the needs of each owner. Just be thankful for your dog and love him the way he loves you.

that is so sweet but i think that it is just in them to be human kinds best friend!!! ( : : )