QUOTE(teongpeng @ Aug 9 2010, 09:13 PM)
why do animals live? what is the purpose of their lives? there in lies the answer.
The most probable answer at this time is the GRAND design "Evolution" that took many years to evolved and became what it is today, living things will continue to evolve until they extinct, if the dinosaur still live, human won't stand a chance.
So, what triggers the beginning of life and why they strive to live is the natural instinct that created all living things. If there is a god, we stop wondering or let nature take it course but if it occur in a spontaneous natural reaction, survival of the fittest is the only rules.
Earth happens to sustain lives and only difference is reproduction method, life span in a food chain. All animals that lives today are the surviver and a part of the food chain which is their purpose, but human went beyond animal life and invented technology, our brain is an ever recording medium unlike animals that can't remember too much.
Knowing we can't derive a satisfactory answer, a lifetime is only to feel as much happiness as we can and reproduce to take care of us when we are old and bury us, if no children, the system have someone to do that.

Memories is our trophy and that is all we need to know.