All non-hermaphroditic creatures, even invertebrates, have to have a means of making males; testosterone is by far the most prevalent mechanism (other creatures are made male/female depending on the temperature the egg is exposed to). Furthermore, ALL members of the same species have both testosterone and estrogens, which have many other functions than anything the public associates with male/female sexes. A testosterone free zone will have little animal species diversity in it.
All non-hermaphroditic creatures, even invertebrates, have to have a means of making males; testosterone is by far the most prevalent mechanism (other creatures are made male/female depending on the temperature the egg is exposed to). Furthermore, ALL members of the same species have both testosterone and estrogens, which have many other functions than anything the public associates with male/female sexes. A testosterone free zone will have little animal species diversity in it.