the argument is that the bowerbird isn't making ecstatic art though, in the sense that while the bird is still expressing an aesthetically driven directive, its

the argument is that the bowerbird isn't making ecstatic art though, in the sense that while the bird is still expressing an aesthetically driven directive, its still biologically motivated, which then remains unexamined beyond preference and aversion in its audience (ie potential mate) the argument the author is instead trying to make is that humans are the only organism that produces ecstatic aesthetic experiences, not simply that it is the only organism that can make pretty things.