Where is the dividing line between culture (man-made) and nature, or does it even exist anymore?

For a long time, I was convinced (with sadness and trepidation) that culture won the game, that we humans had "succeeded" in altering all aspects of life on earth. I was saying to myself, yes, we’d done it and there's no turning back, there's nothing truly “natural" found on this earth anymore. Every corner of the Earth and even our own body, were now forever changed by our way of life, sciences, technologies, our actions, by our culture.

Lately though I’ve began to think...wait a minute, maybe everything is all Nature’s "doing" all along.
How we became humans 200,000 years ago, (homo sapiens) was not our own choice but happened during the long process (4 billion years) called evolution/natural selection.
As we continued to evolve (and still are) we started having “culture" including the use of fire, invention of tools, of art and languages, that are the “natural" consequences of our evolving brain and of the stimuli from the (natural) environment we inhabited and altered ever since. We have come a long way here and now but our one foot is still in Nature. We are of Nature even though we are not totally natural; we are cultural beings. This reminds me of Carl Jung's saying: "Nature must not win the game but she cannot lose."

My artwork is a way to process and visualize my musings on this subject matter which occupies my time, except when I am looking at the birds in the tree besides my living room window.