Evidence conflicts as to whether hamsters are crepuscular or nocturnal. Khunen writes, "Hamsters are nocturnal rodents who [sic] are active during the night...",[5] but others have written that because hamsters live underground during most of the day, only leaving their burrows about an hour before sundown and then returning when it gets dark, their behavior is primarily crepuscular.[citation needed] Fritzsche indicated although some species have been observed to show more nocturnal activity than others, they are all primarily crepuscular.