Walking the Pond

I continually, well increasingly want to remind myself and others of our integral relationship with the planet we live on, and the way we solely develop our anatomy and thoughts in relation to its structure. In researching sleep and the microbiome, I am extremely interested in the fact that light affects the gut microbiome and the production of vitamin D which controls sleep. And how we have a dependence on the 'pond', the 'ocean', we carry within us, and that we have carried with us as we moved out of the sea and began to inhabit the land. The sea - the pond that once surrounded early forms of life is now carried within us. A round organism swimming in the sea becomes a tube, and the walls of our gut are a boundary to the outside.
In this evolutionary process are 'we' responsible for this or did the microbiome in us organise and manufacture this move to the resources of the land?
It is not our anatomy but a shared anatomy, where we host many valuable bacteria, that through our joint production of proteins allow us to survive.
We need a good and solid daily dose of light to perpetuate the processes that sustain us and remarkably regulate our gut and our rhythms of life.