Question: why do we have tears and where do they come from?

Frank Longford answered on 14 Mar 2015:

Good question. The second part is easier to answer – tears are produced by tear ducts just at the side of our eyes next to our nose. They lubricate and clean our eyes so they don’t dry out or become infected all the time. Why we cry when we are upset or very happy however is not so clear. Scientists know how tears are triggered by the limbic system in the brain to accompany strong basic emotional feelings (fear, anger…something, something dark side…) but in terms of evolution how this reaction was developed doesn’t seem to be that well studied. Maybe you could discover it!