Secret Lives of Field Mice Caught on Camera
Did you ever wonder what goes in the social life of a mouse? Or how mice suffering from autism and other neuropsychiatric disorders manage their lives? I don’t suppose many of us have given it much thought, but Dr. Tali Kimchi and her colleagues in the Neurobiology Department at Weizmann Institute are an exception to that assumption. Through research, they discovered that the social interactions of mice are so similar to that of humans, that there is great potential to use them as guinea pigs in studies that will benefit humans.
First in the World Automated Tracking System
Dr. Kimchi devised her research techniques during her post-doc studies at Harvard University. In 2008, she went to work at Israel’s Weizmann Institute, where she spent more than three years building an automated system her team could use to study the relationship between the behaviors of people groups and field mice. Typically, lab experimentation with mice is done with a small cage and two of the rodents, but she built a cage that was three square feet in size. Instead of putting two mice in, she put in five male mice that were strangers to one another and of the same strain and age. The field mice went in well-equipped with a telemetry system that was invented and patented at Weizmann for the purpose of tracking their every movement. And track they did! With their hi-tech infrared equipment, every movement of those mice was recorded.
I’m the Leader Here!
So, you’re wondering. What did the mice do that was so interesting? First of all, within hours of meeting one another in the cage, a class system was developed that remained throughout. One mouse in each of the groups of five chose itself to be King of the Herd, or the alpha male. Next in line came the beta, or the one hoping the alpha would die so that he could take over the tribe. The three remaining mice maintained their lowly positions. The dominant male gave himself total control, meaning he was in charge of everything that went on in those three square feet, including food, water and even mating. The most interaction was noted between the dominant male and the mouse in position #2. Then, to mix things up a little, two female mice were added to the mix. Boy did that upset the balance. Suddenly, all five of the male mice became more sociable. By monitoring each group for 1 ½ weeks, the team identified many social behaviors, including how they found certain companions for rest or activities and how they avoided specific mice or attacked others. Using the results of the study, they learned to predict with more than 90% accuracy which mice would mate. They could also identify many individual behaviors, such as drinking, eating, sleeping, hiding and running. As a behaviorist, Dr. Kimchi found the results fascinating.
Socially Dysfunctional Mice
I really don’t know if this happens in the wild, but the next challenge was to study mice with varying degrees of social behaviors. Mice that were specifically bred with autistic behaviors were introduced into the cages. The results were much different, in that they never established a social order and they were unstable in their relationships. If one of them did declare himself the leader, he was quickly dethroned.
According to Dr. Kimchi, whose test results were published internationally, studying mice can deepen our understanding of all types of social behaviors, including abnormal behaviors as well as aggression, maternal and sexual behaviors, which can be applied to other species. Her research shows that 98% of a mouse’s genes correlate with humans, including hormones and brains. By using mice as models, she hopes her neuropsychotic research can be used to evaluate different treatments for various social disorders.