PARIS: Sick young ants release a smell to tell worker ants to destroy them to protect the colony from infection, scientists said Tuesday, adding that queens do not seem to commit this act of self-sacrifice.&nbsp;Many animals conceal illness for social reasons. For example,&nbsp;sick humans are known to risk infecting others so they can still go to the office &mdash; or the pub.&nbsp;Ant colonies, however, act as one &quot;super-organism&quot; which works to ensure the survival of all, similar to how infected cells in our bodies send out a &quot;find-me and eat-me&quot; signal, according to an Austria-led team of scientists.&nbsp;Ant nests are a &quot;perfect place for a disease outbreak to occur because there are thousands of ants crawling over each other,&quot; Erika Dawson, a behavioral ecologist at the Institute of Science and Technology Austria and lead author of a new study, told AFP.&nbsp;When adult worker ants get an illness that could spread through the colony, they leave the nest to die alone.&nbsp;Young ants, known as pupae, in contrast are still trapped inside a cocoon, making this kind of social distancing impossible.&nbsp;Scientists had already figured out that when these pupae are terminally ill, there is a chemical change that produces a particular smell.&nbsp;Adult worker ants then gather around, remove the cocoon, &quot;bite holes in the pupae and insert poison,&quot; Dawson said.&nbsp;The poison acts as a disinfectant, which kills both the colony-threatening pathogen and the pupae.&nbsp;For the new research, the scientists wanted to figure out whether the pupae &quot;were actively saying: &#39;hey, come and kill me&#39;,&quot; Dawson said.&nbsp;&#39;Altruistic act&#39;First, the scientists extracted the smell from the sick pupae of a small black garden ant called Lasius neglectus. When they applied the smell to a healthy brood in the lab, the workers still destroyed them.&nbsp;Then, the team conducted an experiment showing that the sick pupae only produce the smell when worker ants are nearby, proving it is a deliberate signal for destruction.&nbsp;&quot;While it is a sacrifice &mdash; an altruistic act &mdash; it&#39;s also in their own interest, because it means that their genes are going to survive and be passed on to the next generation,&quot; Dawson said.&nbsp;However, there is one member of the nest that does not sacrifice itself.&nbsp;When queen pupae are infected inside their cocoons, they do not send out the smelly warning signal, the team found.&nbsp;&quot;Are they cheating the system?&quot; Dawson said the team asked themselves.&nbsp;However, they found that the &quot;queen pupae have much better immune systems than the worker pupae, and so they were able to fight off the infection &mdash; and that&#39;s why we think that they weren&#39;t signaling,&quot; she said.&nbsp;Dawson hopes future research will investigate whether queen pupae sacrifice themselves when it becomes clear they will not beat their infection.&nbsp;The study was published in the journal Nature Communications.

Artificial Intelligence

Sick young ants release a smell to tell worker ants to destroy them to protect the colony from infection, scientists say.

Articles tagged with "ants"

'Come and kill me': Sick ants invite destruction to save colony

'Come and kill me': Sick ants invite destruction to save colony