The research, published in the American Journal of Political Science, suggested one of the reasons so many spouses share similar political views is that they were initially - and subconsciously - attracted to each other's body odour.
Researchers had 21 participants classed as strongly liberal or conservative wear gauze pads under their arms for 24 hours to acquire the sample scents, and the pads were then dropped in sterile vials.
The 146-strong test group then gave the pads a sniff test, rating the attractiveness of the body odour without ever seeing the individuals whose smells they were evaluating.
"People could not predict the political ideology of others by smell if you asked them, but they differentially found the smell of those who aligned with them more attractive," study lead author Dr Rose McDermott, of Brown University, said.
In one case, a woman asked if she could take a vial containing one of the pads home, saying it was "the best perfume I ever smelled". The sample was from a man who shared her political ideology.
Another test subject, with different political leanings, said the same sample had "gone rancid".
"While people can choose to dismiss or ignore these signals in favour of more conscious considerations, it appears nature stacks the deck to make politically similar partners more attractive to each other in unconscious ways, at least over the long haul," Dr McDermott said.
Researchers from Brown, Harvard and Pennsylvania State universities were involved in the study.
- Online ODT
