Not only humans are friendly, ants are too. Team members care for the sick by providing joint hygiene measures. This gives the germs a job. They must avoid individual ants’ self-defense and avoid group health care. A new study has been published in Nature Ecology & Evolution reveals that parasites develop a cunning way to escape the defense mechanisms of ants by reducing their ability to detect.
Viruses are organisms that cause disease. Through natural selection, they develop ways to outwit the immune system and gain strength. Another way to support the immune system and fight back is through medical intervention. However, this can lead to unwanted biological changes as seen in antibiotic resistant bacteria. Another strategy is community involvement. Some social groups such as ants try to combat infection through “social defense,” combining hygiene and health care practices to avoid community spread. If the organisms can respond to this type of group behavior, it is not known.
A recent study by Professor Sylvia Cremer and her research team at the Austrian Institute of Science and Technology (ISTA) shows the surprising effects of these types of interactions with microbes. Together, with chemical ecologists at the University of Würzburg in Germany, the scientists took a closer look at social ants, to see how pathogenic fungi respond to the social care process during the infection. The results reveal that the fungi reduce their chemical recognition signals more than the public defense. The study was published today on Nature Ecology & Evolution.
Lots of spores but little grooming
“The fungus infects the ant’s body and then germinates,” explains Barbara Milutinović, one of the lead authors, a former postdoc at the Cremer Group. inside, but nests clean out a lot of germs before they can cause internal infections.” Sklodowska Fellow at the Ruđer Bošković Institute in Croatia. Scientists set up an experiment where Argentine ants (It has an epithet) are pathogenic Metarhizium fungi can be in the absence or presence of organs. “We found that the fungi have changed a lot due to the attention of the ant workers,” Milutinović continues. Over ten stages of infection, the fungi that experienced the cleanliness of the ants increased their production compared to the fungi that accompanied the individual ants. “Producing more spores will help the fungi to prevent parasites by helping the nests. However, we were surprised to see that the ants showed little self-defense against the parasites,” Sylvia Cremer adds. “This suggests that the spores are now difficult to detect by the ants.”
Fungi lose their habit chemical situation
To investigate why worker ants have difficulty detecting fungi and to explore possible ways to detect fungi, the scientists contacted an ant ecologist. chemist of the University of Würzburg. Local professor Thomas Schmitt explains: “Fungi, which were adapted to the host in the community were detected with less intensity, due to the strong reduction of a special fungus compound called ergosterol.” Ergosterol is an important membrane component, which all fungi have. By exposing ants to pure fungal ergosterol or a slightly different non-fungal vertebrate strain, the researchers showed that only the fungal compound stimulated strong grooming. Milutinović sums up: “This shows that fungal pathogens react to the presence of ants that care by reducing their fungal symptoms. They are no longer considered a threat of death and can escape the social defense of the colony .”
Studies highlight the influence that social hosts have on their organisms through group behavior. “It’s interesting how collective hygiene measures create strategies to avoid parasites. It would be interesting to see how the ant colony will react in turn. Maybe they are more sensitive when they recognize lower and lower fungal symptoms,” Cremer concludes.