What is a biophysical cause of ecotourism?

ecotourism
em asked:

This is for my year 12 geography assignment. The main topic is “What impact does ecotourism have on our society?” and one of the sections needed to be covered is “causes” (of whatever our topic question is). In the causes section we must include the biophysical and the human causes, and the biophysical part doesn’t make much sense to me…
My teacher said one point was “the attraction of people to nature/wilderness” but I don’t get this and I need more points to add to this section.
Any help will be very much appreciated!