As our kind pushes outward into space we express a paradox of looking for life while simultaneously bringing it along. No species is an island, and though machines serve us well there's no sense fighting our nature-loving nature. Life itself is interesting, much more than where you find it, and forgive me but just looking for it using the fingers of technology misses something important, something vital, whatever you call that sweet mystery that at last is found.
One case to examine would be the currently ignored Phoenix lander. It managed a breath-taking retro-powered landing on Mars several sols ago to widespread media coverage. Since then ho hum, as the easy bake ovens aren't and don't, the second string announcement of water is passé given decades old evidence from multiple devices, and all in all it hasn't done much to fever the public imagination for things Martian. It will be sad if it garners more attention slowly freezing to death than any formerly acquired by its clumsy attempts to analyze cold clumpy red dirt.
It's wonderful to think how far humanity has come, from our initial frenzied phase to today's more patient, base-building path. But one problem explorers have yet to conquer, one limitation shared by all in common, was that they had to bring their supplies along with them. Only those serving aboard long-term manned space stations ever expected to find a meal waiting for them (and even then of course it was shipped up previously).
People eat a lot. They breathe a lot. They spray waste fluids and leak gases and produce copious amounts of solid biohazard at (if lucky) regular intervals. At some point the relative expenses come into consideration, between direct storage and supply of raw materials (storage/disposal of waste materials too) to a self-contained, "closed" bioregenerative system. Supply ships may be less expensive but life has several advantages, not least among them self-replication and a lack of packing materials!
Estimates range on a mission duration required to cost-justify bringing chickens and feed rather than simply shipping up frozen nuggets, but their low end would be no less than ten years. That's an optimistic though entirely reasonable stint for a permanent moon base, but still impractical for even the most avid Mars visitor. But sooner or later we've got to learn how to take more than just ourselves. The garden, and its attendants large and small, also have to go. We have to take more of our home along, in order to make space our home.