Orli Snir, a biologist at the Rockefeller University in New York, couldn’t keep her ants alive. She had plucked pupae from a colony of clonal raider ants, where the sesame seed-size offspring that looked like puffed rice cereal were being fussed over by both younger larvae and older adult ants. Then she had isolated each pupa into a tiny, dry test tube. And every time, they drowned.
More specifically, each pupa was leaking so much watery, golden-tinted fluid it was struggling to breathe. But they lived when Dr. Snir whisked the fluid away with a capillary tube. Her humble observation led down a strange path of experiments toward a bizarre but inescapable conclusion: This mysterious ant goo functions a lot like milk.
Not just one ant species uses this milk, either. Perhaps all ants do, according to a paper led by Dr. Snir that was published Wednesday in the journal Nature. It adds ants among other unexpected creatures like pigeons, spiders and beetles that feed each other milk-like fluids. And much like milk in mammals, it knits together ants of different generations — and the larger ant society, too. [Continue reading…]