Here is a thought (a thought that I've never seen expressed before):

Biology (or perhaps evolutionary biology) is to conservation ecology as comparative physiology / comparative anatomy is to medicine.

People have tried to ground medicine (and psychiatry as a branch of medicine) in the biological sciences. A way of saying 'psychiatry deals in facts too so it clearly isn't SOLELY a matter of value colonialisation' (as some anti-psychiatrists / social constructionists have thought). But the jump from the biological sciences to medicine is problematic in a number of respects...

One feature is that psychiatry (and medicine) is applied. To say that someone is mentally and / or physically ill / disordered is to say that that person would be better off if that person were not mentally and / or physically disordered. The application seems to make it evaluative.

Similarly, conservation ecology is all about maximising 'diversity' (similarly to how medicine / psychiatry is about maximising 'health'). There are different measures of 'diversity' (e.g., morphological / phenotypic difference, difference (with respect to evolutionary history) from other surviving species, the role the organism plays in an ecological niche (e.g., as a prey for a different species or whatever). It has been thought... That while there are many measures of 'diversity' none is equivalent to the concept itself (and of course the concept of diversity is normative in the sense that diversity is something that it is good to maximise).

One could argue that medicine in analogous. It involves (as does psychiatry) this notion of 'health'. While there are many different measures of health none is equivalent to the concept itself (which is partly normative in the sense that organisms would be better off if they were healthy).

Interesting.

Or interesting-ish.

Not sure...