The polar icecaps are melting. Is it OK to have a child? Australia is on fire. Is it OK to have a child? My house is flooded, my crops have failed, my community is fleeing. Is it OK to have a child? It is, in a sense, an impossible question.

The many problems with a common forensic technique called “pattern-matching” — comparisons of bite marks, tool marks, hairs, shoe prints, tire tracks, or fingerprints.