As we all know, hamsters are very active rodents. In the wild, they spend part of the day in their burrows to hide from predators and adverse weather conditions, and from dusk to dawn they prowl for food and water. Data shows that hamsters foraging in the wild can run at least 10 kilometers every night.

After being raised artificially, the hamster’s running instinct and energy for exercise have not weakened. Therefore, running wheels have become a must-have item for raising hamsters.

However, over the years, scientists, researchers and animal rights advocates have There has been ongoing debate about the behavioral nature of hamsters running on running wheels in cages. Activists say running on a running wheel is a neurotic or stereotyped behavior caused by captivity. Some researchers believe that hamsters seem to like and enjoy running on the wheel and even display unhappy behavior after the wheel is removed.

In response to this type of controversy, neurophysiologists Johanna Meijer and Yuri Robbers of Leiden University Medical Center in the Netherlands conducted an experiment in 2014: placing running wheels in the wild to see whether rodents in the wild still Will run on it. A paper published in Proceedings of the Royal Society B: Biological Sciences describes how they set up running wheels in a natural environment and then filmed wild animals using them.

They installed the wheels at two different locations frequented by wild rodents. One is placed in a tree-lined urban area and the other is placed in a very remote environment. This way, they can see if the presence of humans has an impact on the use of the running wheels. They also placed food and motion detection cameras at each site to record any critters that happened to pass by.

In the first two years, the running wheel was used a total of 1011 times. . Among them, 734 were mice, and one mouse ran for an incredible 18 minutes. Some slugs, rats, shrews and frogs were also attracted. However, the frog only jumped around the wheel, and the slug seemed to crawl onto the wheel out of sheer curiosity - but the other animals rolled the wheel correctly.

A variety of animals use running wheels, but rats are the most common

Over three years, researchers recorded the use of running wheels by more than 200,000 animals. Of the rats that passed by, 1.7% attempted to run on the wheel. But of the animals that pass by, only 0.4% try it. Obviously, in the wild, rats really love running compared to other small animals.

Among them, when the food that attracts small animals is removed, although the number of mice visiting the recording point decreases, the proportion of mice visiting the running wheel increases. The researchers believe this means that running on the wheel provides the mice with a natural pleasure reward, even if there is no associated food reward.

In addition, when Johanna Meijer and Yuri Robbers compared the running times of wild and captive mice, they found that both groups also spent approximately the same amount of time on the running wheel per run.

If the running wheel is indeed caused by captivity, then wild rats are in nature. You won't be able to use running wheels. However, the above experiments show that when the running wheel is placed in nature, wild rats will frequently use the running wheel, even in the absence of extrinsic rewards. And the round length of wild mice's wheel-running behavior is consistent with that of captive mice. This discovery overturned the stereotype of stereotyped behavior and showed that wheel running is a selected behavior or a natural behavior.

Maybe more than one motivation is at work when hamsters use running wheels, but in any case, one thing is for sure: based on the fact that wild hamsters also use running wheels in the wild, in captivity The running activities of dogs are actually satisfying their natural desires rather than artificially created needs.