Daily activity rhythms are nearly universal among animals and their specific pattern is an adaptation of each species to its ecological niche. Owing to the extremely consistent nocturnal patterns of activity shown by golden hamsters (Mesocricetus auratus) in the laboratory, this species is a prime model for studying the mechanisms controlling circadian rhythms. In contrast to laboratory data, we discovered that female hamsters in the wild were almost exclusively diurnal. These results raise many questions about the ecological variables that shape the activity patterns in golden hamsters and the differences between laboratory and field results.

Foraging theory posits that animals should maximize energy gains while minimizing risks, the largest of which is usually predation. For small burrowing mammals the best measure of risk avoidance may be the time spent in the burrow, although this measure is rarely examined. During the spring of 2005 and 2006 we recorded the foraging behavior of female golden hamsters in their natural habitat in southern Turkey. Data were collected with a data logger and by direct observations. Female golden hamsters averaged 64 min per day above ground in a series of foraging trips with a mean duration of 5.5 min. Two nursing females increased their time out of the burrow by a factor of 6-8 times over the course of 16 days by increasing both the number of trips and the length of each trip. These results show that hamsters spend little time out of the burrow, thus minimizing risk, but they also show that time spent out of the burrow is related to the energy needs of the hamsters; lactating females with high energy needs exposed themselves to much greater risk than did nonlactating females.

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Knowledge of escape behavior contributes to an understanding of a species' natural history and provides insights into the physical capabilities of that animal in a natural setting. Using an "approach stick" to standardize the "threat" to which an animal responded, we examined reactions of the Anguillian anole, Anolis gingivinus. As in other anoles, A. gingivinus allowed relatively close approaches, followed by the behaviors of squirreling, running, jumping, or combinations thereof. The most important factors determining which action was taken were the diameter of the lizard's perch and the direction the lizard was facing. Amount of sun exposure also had an effect on behavior, whereas sex of individuals did not. Some visual aspect of the putative predator also had an effect, determining in part the distance at which the animal fled.