A new study found that hyenas use bacteria to send detailed messages to other animals. Scientists’ believe that this discovery may pave the way for a new perspective of animal communications.
According to lead author Kevin Theis, a postdoctoral researcher from Michigan State University (MSU), “When hyenas leave paste deposits on grass, the sour-smelling signals relay reams of information for other animals to read. Hyenas can leave a quick, detailed message and go. It’s like a bulletin board of who’s around and how they’re doing.”
The researchers investigated the various groups of striped and spotted hyenas found in Kenya. “Scent posts are bulletin boards, pastes are business cards, and bacteria are the ink, shaped into letters and words that provide information about the paster to the boards’ visitors. Without the ink, there is potentially just a board of blank uninformative cards,” said co-author MSU zoologist Kay Holekamp.
Theis and Holekamp used a different method for their research. Instead of the traditional culture-based methods, they used molecular surveys of the microbes instead. This new method allowed them to view for the first time how varied the bacteria in animals’ scent glands are.
“There have been around 15 prior studies pursuing this line of research. But they typically relied on culture-based methods, an approach in which many of the similarities and differences in bacterial communities can be lost. If we used those traditional methods, many of the key findings that are driving our research wouldn’t be detected at all,” said Theis.
The researchers discovered that the diversity of the microbes consistently varied in hyena groups as well as gender differences in spotted hyenas. What is remarkable is that these variations are linked to the scent glands’ odor attributes which could be inferred is caused by the bacteria themselves.
With the new method, they were able to integrate prior scent data from untamed animals. But this will allow further research in this area of study.
As Theis said, “Now I just need to get back into the field to test new predictions generated by this study. The next phase of this research will be to manipulate the bacterial communities in hyenas’ scent glands to test if their odors change in predictable ways.”
The study was published in the Nov. 11 issue of the Proceedings of the National Academy of Sciences.
