Editing Hamster (section)

===Chronobiology===
Hamsters can be described as [[nocturnal]] or [[crepuscular]] (active mostly at dawn and dusk). Khunen writes, "Hamsters are nocturnal rodents who are active during the night",<ref name="Kuhnen, (2001)"/> but others have written that because hamsters live underground during most of the day, only leaving their burrows for about an hour before sundown and then returning when it gets dark, their behavior is primarily crepuscular. Fritzsche indicated although some species have been observed to show more nocturnal activity than others, they are all primarily crepuscular.<ref name="Fritz"/>

In the wild Syrian hamsters can [[hibernate]] and allow their body temperature to fall close to ambient temperature. This kind of [[thermoregulation]] diminishes the [[metabolic rate]] to about 5% and helps the animal to considerably reduce the need for food during the winter.<ref name="Kuhnen, (2001)"/> Hibernation can last up to one week but more commonly last 2–3 days.<ref name="britishhamsterassociation.org.uk">{{Cite web|url=http://www.britishhamsterassociation.org.uk/get_article.php?fname=journal/hibernation.html|title=Welcome to the British Hamster Association Web Site}}</ref> When kept as house pets the Syrian hamster does not hibernate.<ref name="britishhamsterassociation.org.uk"/>