IF, as Christians believe, the Earth was created in this universe as a home for man to have dominion over that guarantee would absolutely be necessary. This all depends on whether Gods intention for creation was a relationship with man or a relationship with what ever developed out of his created initial conditions. Christians it is my understanding are of the belief that creation was intended for man and not some other highly developed creature. As for chance development, the universe IS full of billions and billions of apparent opportune sites for life or creatures of self consciousness to have developed yet there has been absolutely no verification of life outside this orb. We should be awash in life if given the time span that has passed the universe were an opportunistic place for life to develop and correspondingly man as a creature God intended to have developed. That being said though I agree that this apparent rarity of discovered life in the universe does not guarantee that man wouldn’t have developed eventually according to Gods specially chosen initial conditions. It would seem though more likely that man would not have developed than the converse if left merely to chance given the time span we have to work in at least in the sense of man being what God were waiting for to develop in his image since the bible clearly states God as wanting man to develop. The bible is a story of not what developed through chance given Gods initial conditions but one of what God directly intended to create. I see what your saying about things acting according to their nature but we still are left with the question of who or what is the originator of the development of that nature. The bible is clear that all things act according to the natures that God infused and sustains within them. The bible is also clear that the creation of man and the creation of other creatures were separate events. The earth was populated with life and then man was created not from this established life but from the inorganic dust of the ground as a separate event in itself. The Genesis statements themselves indicate that man developed not from the advanced life forms found on earth at the time but in retrograde from the primordial conditions of the dust of the earth in apparent violation of the laws of undirected evolution.