While it would be highly impractical (not to mention awkward) if everyone kept a microscope handy to study the DNA of a potential love interest, the good news is that we can literally sniff each other out, finding the ideal genetically suitable partner using our nose.
Davis says this is because we look for complementary immune systems that enhance the chance of our offspring’s survival. In other words, the path to true love is more sci-fi than rom-com.
The basis of this evolutionary psychology comes from the delightfully termed "sweaty T-shirt" experiment by Swiss zoologist Claus Wedekind in 1994. The idea was to test women's sensitivity to male odors. He gave 44 men clean T-shirts to wear for two nights without deodorant or cologne. These were returned to his laboratory where they were put in separate boxes. Female volunteers then sniffed each box (as you do), and described each sweaty T-shirt’s smell in terms of intensity, pleasantness, and sexiness. The experiment found that women preferred the scents of T-shirts worn by men whose genes were most different from their own.
While Davis admits that more research is needed, at least sniffing out true love makes a nice change from the usual cliched advice that gets trotted out. And if you're stuck for conversation on a first date, why not suggest that you smell each other? Surely the ultimate icebreaker.