COOL mothers produce plumper babies – at least among mice. Feeding pups and producing milk is hard work, and generates so much waste heat that a mouse risks overheating. This constrains the amount of milk a mother can produce, says John Speakman at the University of Aberdeen, UK.
When Speakman shaved the backs of nursing mice to allow them to lose more heat through the skin, he found that milk production and the weight of the litter both increased by 15 per cent (The Journal of Experimental Biology, ). Once shaved, females kept cooler and could afford to eat…
