Research suggests 50% of all UK babies have shared their parents’ bed by the time they are 3 months old. Figures for breastfeeding babies appear to be much higher, 70-80%. When we consider the relative immaturity of the human infant (we are born relatively ‘early’ compared to other mammals) and the constituents of breastmilk, we can see that human babies need to feed regularly and they are dependent on close promixity. Close proximity helps regulate temperature and breathing rate. The cultural expectation that breastfeeding parents sleep separately from their babies doesn’t appear to fit with the evolutionary perspective.