What is the meaning of life, from an atheists perspective?

If atheists believe that humans are just smart animals, like goats, only smarter....then what is the point of life? If we are just animals, why do we get up in the morning and fight traffic just to get to work and make a few bucks to eat? Why aren't we smart like zebras and kangaroos and just walk around eating gr for free? If humans were not put on this earth by a creator and destined for greatness, then aren't we living a lie? We were all mistakes, freaks of nature, according to atheists. None of us should really be here. We have no purpose, no reason to go on. We are all just monkeys that don't realize we're monkeys and we're just waiting to die so bugs can eat us, right? So, what do atheists see as the point behind all of this? If there is nothing inherently special about humans, if we aren't meant to live out some great destiny predetermined by God, then why put up with this crazy circus we call life?