People who believe in the theory of evolution state (correctly) that we humans are descended from the same common ancestors as modern-day primates. People willfully ignorant of the science behind this assertion sometimes lash out in fear for their beliefs, finding it offensive that we are somehow related to chimpanzees and not perfectly created by a mythical being.
I say take the comparison further. Not only are we directly related to lowly chimpanzees but we can trace our evolutionary lineage all the way back to the first bacteria. Anybody with a passing interest in science already knows this, but a close reflection upon this evolutionary journey just might point us towards the meaning for existence along the way.
Bacteria are the most plentiful form of life on the planet and they are the first signs of life that scientists look for in outer space. Bacteria are remarkably resilient and can multiply their numbers exponentially given the right resources, not unlike humanity.
We've carved out niches in almost every environment on our planet and already have started looking at the stars like Tiktaalik peered out of the primordial water at the unexplored universe. We have left such an imprint with climate change and modification of the environment that geologists now refer to our time on earth as the beginning of the anthropocene.
Could we, or the artificial intelligence we eventually create, be simply giant bacteria magnified through the lens of evolution? Our purpose in life may be simply to spread as far and wide through the universe as resources allow until it too dies the slow death of entropy.