ONE of the biggest puzzles of evolution is how our brains got to be big compared with those of other animals. It now seems possible that a hormone which allows the placenta to burrow into the wall of the uterus in some primates might also have played a key role in brain evolution.
“A hormone which allows the placenta to burrow into the uterus wall might have played a key role in brain evolution”
Our brains account for a whopping 2.4 per cent of our body weight, three times the corresponding percentage in one of our nearest relatives, the orang-utan,…
