Here's [1] what appears to be a good one (or, at least, it has some citations to other papers which might be better) -- the first section after the abstract is

Here's [1] what appears to be a good one (or, at least, it has some citations to other papers which might be better) -- the first section after the abstract is an intro to circadian rhythms, including references to food zeitgebers in rats, rabbits and adorable hamsters. IIRC there doesn't appear to be a strong effect in humans, but I'm slacking off as is and won't be digging up a reference for that XD [1]: http://ajpregu.physiology.org/content/274/6/R1751.short http://ajpregu.physiology.org/content/274/6/R1751.short