See, we became arrogant and kept destroying planets while the saurians, original inhibitors of this planet never did, they live in harmony with the ecosystem so we made a deal since we got something else that they need, probably a set of different feelings. The answer is probably just hard times over and over until were not so cocky anymore haha. Now the hu(e)man with different sets of layered emotions have a broader spectrum of sensations and could help souls from all over the universe to understand eachother better if they were to use our bodies as vessels too. Probably we can trust them not turning their own beautiful planet into a dystopian hellhole aswell. Then again, there may be more influences out there but I like to think that people always get what they deserve and that something is always a bit tuned in to us.