Biotic ethics

Callicott is on a quest to find where (and how) our ethical thoughts first originated. He aims to follow the development of our ethics through history, with specific references to Leopold's "Land Ethic."
Did our ethics come from God (or gods)? Callicott says that can't be right because scientific principle states that such supernatural explanations (like religion) can hold no water with regards to natural phenomena.
Hume and Adam Smith believe that our ethics came from our animal feelings and sentiments.
Darwin argues that the tight bonds that families have with their kin spread throughout larger populations, giving rise to such ethical feelings. Callicott goes further, quoting Darwin: "the individual is a member of a community of interdependent parts" (203).
Callicott proposes ecological thought, which also involves an individual's relationship with the whole (in this case, the whole environment).
So ethics and society or community are correlative.
But it is also true, according to Callicott, that ecological relationships determine the nature of organisms, not the other way around (207).
The whole ends up shaping the parts that make it up. So, the very soil, solar energy, food chains and death and decay are part of this biotic whole. We are in there right along with everything else, and I agree that there is a certain level of respect that goes along with being a part of this whole. It is not as if we will no longer be a part of the whole if our laziness and neglect of consequences of our actions will get us kicked out. We will be in in no matter what, so we best continue thinking how we affect the whole, because this whole represents us as well.