The test is reasonably well known, however MHC's are thought to be one of the main differences selected for. These are part of the immune response, so more variation means you should be able to have a broader range of resistance.
And yes they do smell it, the test i read of had 30 men wear a tshirt, do 30 mins of exercise, no deoderants etc. the tshirts were numbered or sometihng, then given to the women to smell. In this test close relations didnt smell as good as people who werent as closly related.
Scientists arent daft enough to claim that its smell if theres another more sensible reason. Everyone smells if not wearing deoderant etc, the test is fine. Once again leaving a good correlation between symmetry and smell.
Unseul
Give a man a fire and he's warm for a day. Set a man on fire and he's warm for the rest of his life....
Do unto others before they do unto you.
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