Ice, testing the genders, unruly crowds...

The differences between boys and girls, the discovery of the oldest turtle specimen that has turned turtle science on its head, the discovery of an enormous plume of water vapour on Enceladus, how calving of ice shelf gives an insight into icebergs and climate change, how robot lizards help us learn more about how lizards get themselves noticed, and the link between serotonin and osteoporosis. Plus, in 'Stuff and Non-Science', are crowds as volatile and unruly as we think?