Text written in Basque and translated automatically by Elia without any subsequent editing. SEE ORIGINAL

The queen's smell makes the rest of the females sterile

In the colonies of naked Sator rats, the queen is the only one who reproduces and secretes a compound to prevent the rest of the females from reproducing.

An international study conducted under the guidance of the Max Delbrück Center in Berlin, Germany, has revealed that royal nude rats secrete a volatile compound that makes the rest of the females in the group temporarily sterile. The discovery was published in the Nature magazine.

Naked rats of Sator (Heterocephalus glaber) are animal models known in the research for their curious biology. Originally from Ethiopia, Kenya and Somalia, they live in underground galleries. They are interesting for research because, among other things, they have a very high life expectancy compared to other rodents of their size, which can live up to 29 years. In addition, they have a very low cancer rate and feel very little pain.

In addition to these characteristics, naked rats are eusocial animals, i.e. colonies are organized around a fertile queen, while the rest of the females do not reproduce. These females raise the queen’s offspring, look for food, and basically care about keeping the colony in good condition. Eusociality is very rare in mammals, but is more common in invertebrates such as bees, termites or ants.

“Even if the Queen is removed from the group, the effect continues because of her smell.”

The researchers wanted to clarify the mechanisms by which these rodents maintain their eusociality. They suspected that smell could be important, as it happens with eusocial insects. Therefore, mass spectrometry was used to identify which compounds were present in the odors secreted by the queens. Among others, isopropyl myristate, a compound commonly used in cosmetics, was found. It doesn’t smell like it’s human, but it smells like it does for naked rats.

When the queen dies in the colonies of these animals, within a few days there are fierce rivalries and reproductive behaviors among the members of the group. As soon as the first female becomes pregnant, she directly becomes the next queen. The queen secretes isopropyl myristate and raises the level of prolactin in all other females, a hormone that reduces fertility. In this way, the competition ends. The researchers also found that even if the queen was removed from the group, the effect continued, caused by her smell.