Your statement presupposes there is, or can be, a world other than "the natural world", whatever that means to you.
Since morals and ethics are simply value standards for Homo Sapiens behavior, determined and set by Homo Sapiens, it would seem a scientific understanding of Homo Sapiens would be required to form any kind of informed opinion on the matter.
After that, it seems to be a matter managing competing needs, wants, and desires in a way that promotes social cohesion and stability. This seems to require a multifaceted understanding of human behavior, both on the individual psychological level and group or social behavior and psychology. You seem to be under the impression that science is only quantitative in method, but it is in fact, both qualitative and quantitative in it's inquiries.
I'm seeing lots of need for science and not a whole lot of need for philosophy.