Survival

Yesterday, In science we watched an Eyewitness movie called Survival. It is about the way living things adapt and survive in their surroundings using their environment, instinct and tactic. I found interesting that a wildebeest is born and a few minutes later it can run faster then an human, professional runner. I also found it interesting that there are so many different way that animals survive and they can learn these ways so quickly. But then animals need to learn survival skills very quickly when they are in the while so that they are not vulnerable to predators.Two questions I have are :

1. Is there a certain chemical in the brain that trigger the instincts that animals have?
2. With magnetism and migration how does it work?

A interesting survival video: