> But, presumably, if they were to lose more weight in winter be being awake than asleep, they'd just go to sleep. This is quite a leap of faith, that they can

> But, presumably, if they were to lose more weight in winter be being awake than asleep, they'd just go to sleep. This is quite a leap of faith, that they can do this calculation. There's some kind of feedback mechanism going on with "if food is plentiful at a certain time, don't go to sleep", and evolution may have optimized this to avoid losing weight in typical scenarios, but evolution doesn't perform that well in outlier situations.