Is playing football like falling in love? That question, which would perhaps not occur to most of us watching hours of the bruising game this holiday season, is the focus of a provocative and growing body of new science examining the role of oxytocin in competitive sports.
Historically we've enjoyed arguing that women are inherently different to men, not only in our physical lady-bits but in our temperament, abilities and behaviours. Testosterone and other hormones, different brain structures, they all lead to certain inevitable "hard-wired" gender-based differences and, even, inequalities.
Your brain doesn't like to keep secrets. Studies at the University of Texas, Austin, have shown that writing down secrets in a journal or telling a doctor your secrets actually decreases the level of stress hormones in your body. Keeping a secret, meanwhile, does the opposite.
Looks aren't everything but love, it would seem, is far from blind. Across cultures and sexes, some features hold greater appeal. "More symmetrical faces do seem to be rated more attractive," says Tamsin Saxton, a senior lecturer at Northumbria University and part of the evolution, perception and behaviour research group. "The theory goes that your genes provide a template for symmetrical bodies, symmetrical face. [When] there's some sort of problem - you get ill or you encounter some problem with the environment - that can sometimes throw the symmetry off a little bit," she says. "So it might be that if you are picking a symmetric partner then you are actually picking somebody whose genes are fairly well suited to the environment around you."