In 1997, a team of scientists reared several chicken eggs in two different incubators: one was a normal, sterile incubator, while the other one was infused with the sweet, fruity aroma of strawberries. Sometimes, they even rubbed the experimental group with strawberry aromas straight on the shell.
Once the chicks hatched, much to the scientist’s amusement, the few baby chickens that had been exposed to strawberries while still embryos loved the scent and the taste of it: they liked strawberry-flavored water and spent more time in strawberry-scented spaces.
Loving strawberries doesn’t have much of an impact on a chicken’s life, but since then, a growing body of research across the animal kingdom started noticing that many oviparous animals start being aware of their surroundings, predatory risks, and food availability while still an embryo by feeling, smelling, and seeing through their eggs.
“We have long thought of eggs not as having a large suite of capabilities,” says Karen Warkentin, a biologist at the University of Boston who studies embryonic learning in frogs. And while obviously, in some ways, that’s true — they’re not very mobile and not that developed — eggs are still subject to the laws of evolution.
