The abortion and euthenasia debates depend heavily on questions of personal identity. One of the most important decisions in 20th US history was Roe v. Wade. The courts were persuaded to rule as they did largely due to the influence of the metaphysician Judith Jarvis Thomson's famous paper in defense of abortion (among other philosophical arguments made).
I mentioned in an earlier post that in most interdepartmental dialogues, the philosophers will almost inevitably know far more about the other disciplines than those in the other disciplines will know about philosophy (see here for an example). This is understandable as there is just about a philosophy of everything. So I agree that there should be more collaboration but I think most of what is prohibiting that constructive dialogue is the arrogance and ignorance seen in people from some other disciplines who don't know a lick about what philosophers are up to. Check out this, this and this just examples from the ignorance of physicists (though in recent years this seems to have started to change among physicists especially theoretical physicists due to the work of philosophers of science on the problem of time, e.g.).