According to a study, some naked mole rats were born just to clean toilets

Maybe you live in a household that likes to divide tasks. You pick up the dishes while someone else does the trash. If so, you’re not that far removed from the habits of a naked mole-rat, according to a new study.

The results were published in the journal on Wednesday Scientific advancesshow that individual naked mole rats perform specific tasks for their colony, including digging, carrying garbage, and cleaning “toilets.” The study shows that the rats engage in a form of task allocation that the researchers say helps the colony function more efficiently.

“Overall, our results reveal the diverse roles of breeders and the remarkable behavioral diversity among non-breeders, highlighting the complexity of naked mole-rat social organization,” they write.

An elusive social system

Naked mole rats (Heterocephalus glaber) are small, almost hairless rodents that live in large colonies underground. These colonies can consist of several hundred individuals and extend over kilometers of tunnels.

These colonies are eusocial, meaning they exhibit the highest degree of organization in the social behavior of animals. In eusocial systems, a single female and a few males produce all of the offspring while most other individuals are busy with labor. Bee colonies are another common example of a eusocial system. Remarkably, naked mole-rats are one of only two known mammal species that exhibit this social structure.

Much like bees, scientists have done it found that naked mole-rats perform a variety of tasks, but it was unclear whether individuals consistently stick to specific tasks or are more flexible. The answer to this question has long eluded researchers due to the challenge of monitoring an entire underground colony over long periods of time, but a team led by Masanori Yamakawa of Kumamoto University in Japan found a way.

Persecution of an underground workforce

Yamakawa and his colleagues developed an automated radio frequency identification (RFID) system to monitor 102 naked mole rats in five colonies for 30 days.

Each colony assigned specific functions to different “chambers,” typically including a nest, a toilet, a trash can, and six additional chambers. In the nest the animals huddled together and rested, in the garbage they deposited waste like excess food or dried feces, and in the toilet – well, you get the idea.

The researchers implanted microchips into the mole rats and installed detectors throughout their colony boxes, allowing them to track where they went and which individuals they interacted with. While the breeding cohort stuck together, the non-breeding individuals could be divided into six “clusters” based on their behavior.

Based on the chambers in which they spent extended periods of time, the researchers concluded that these groups performed different, specific tasks. For example, individuals in Group 1 showed high mobility and significant garbage chamber occupancy, suggesting that they may serve as garbage collectors. Meanwhile, Group 5 people who have spent a lot of time in toilet rooms could be responsible for cleaning the latrine.

The researchers found that individuals’ body weight and age had a significant impact on their cluster assignment, suggesting that naked mole rats’ tasks may change as they grow. But most people (95%) stuck with their assigned roles throughout the 30-day period of the study, suggesting they don’t swap tasks often. Sad times perhaps for the toilet bins.

This work provides a detailed look into the complex social structure of this elusive species. Future studies could build on these findings by manipulating variables to trigger behavioral changes or incorporating other observation methods, the researchers said. This could help “uncover the underlying mechanisms that drive cooperative society,” they wrote.