As I’ve mentioned before, living in a large densely-packed social group, like a city or an ant colony, comes with some drawbacks – perhaps worst of which is the risk of catching a contagious diseases. Earlier this year I wrote about research showing that raider ants treat injured workers’ wounds, helping them to heal. Now, a new study shows that the queen can pass on resistance to diseases she’s encountered, arming her workers against pathogens.

Adele Bordoni and her colleagues at Florence University in Italy exposed hibernating queen acrobat ants (Crematogaster scutellaris) to a non-lethal dose of live fungal spores (Metarhizium anisopliae). After emerging from hibernation the queens were allowed to lay their first batch of workers, whose survival the team then tested by exposing them to high levels of the same fungus. They found that offspring of queens exposed to live fungal spores were 18% more likely to survive than offspring of queens treated with heat-killed spores.

Ants have evolved many tactics to stop infections from becoming epidemics, such as antimicrobials, social wound-treatment, and even selfless acts of suicide. This study is the first to show that ant queens can pass enhanced resistance on to their offspring based on the environmental conditions they have experienced. The ability to pass resistance from generation to generation may be a crucial adaptation to living in large groups.

Want to know more?

• Bordoni A, Dapporto L, tatini I, Celli M, Bercigli M, Barrufet SR, Perito B, Turillazzi S. 2018 Trans-generational immunization in the acrobat ant Crematogaster scutellaris. Biol. Lett. 20170761. 10.1098/rsbl.2017.0761