Orli Snir was only a couple of months into a postdoctoral fellowship at Rockefeller University when her research project fell apart.
Snir had a background in evolutionary biology, having worked with plants and flies. She had moved from Israel to Daniel Kronauer’s lab to begin research with ants. Rather than despair at the bad luck so soon after her arrival, Snir suggested that she simply spend some time observing her new research subjects.
The task suited her — her curiosity is what drove her into the research world. Asked how friends and family would describe her, Snir responded that they would probably say that she puts a lot of effort into relationships. “I try to really see who’s in front of me, and try to really understand where he’s coming from, and what does he need? For me, it’s the most important thing, to establish a meaningful relationship,” she said. “Being observant is a good feature for that.”
She watched as the adults carried the newborn larvae over to the stagnant pupae, encased in their cocoons. Ants have been used in research for decades, but even ant specialists hadn’t given much regard to the odd interaction between ant generations. But why? Even Snir’s 4-year-old son was curious when the detail was relayed to him at home, but there was no answer in any of the scientific literature out there.
Upon separating them, Snir discovered that there was a liquid seeping out from the pupae’s capsules. At first, it was clear, with an almost golden sheen, but got cloudy as time went on. If left on the pupae for too long, they would either drown or die from infection.
The liquid was rich in enzymes, fats, and carbs; by dying it blue, Snir discovered that both the adult ants and the young larvae were ingesting it. In fact, it was the only source of nutrients the larvae had.
The discovery of the ant “milk” excited the scientific community. “As an ant biologist, I think the discovery of ‘ant milk’ might be the single biggest research finding during my lifetime,” Alex Wild, an entomologist at the University of Texas, wrote on social media. It helped explain why ants, unlike many other insects, form such strong community bonds.
“It’s a molecular mechanism for social interaction,” Snir said. “It goes beyond the ant colonies. It goes into understanding how evolution is actually done.”
There was one person who wasn’t as enthralled by the discovery: Snir’s son. “With kids, they really like to ask questions, but then when you answer back, at that stage, nothing is shocking.”
— Allison DeAngelis
