Embryonic education: How learning begins long before birth

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By Guy Lewy

NEWLY hatched turtles head straight for the sea and tadpoles recognise a predatory salamander the very first time they see one. But what may, on the surface, appear to be a primordial instinct can sometimes hide a deeper, stranger truth: that our first lessons in __life come before birth itself.

Over the years, studies of young animals belonging to a range of species have pushed back the known onset of learning. “We tried earlier and earlier,” says Ludovic Dickel, who studies cuttlefish at the University of Caen Normandy in France. “In the end, we questioned embryos.”

From this research, a trend is emerging. Birds in the egg are listening to their mothers; lambs, like human babies, can be taught about food before birth; and some embryos watch the world through their still-developing eyes. And because these are all examples of acquired knowledge, not instinct, they can also be manipulated.

Take taste. Stories of human babies developing a preference for certain foods while still in their mother’s womb aren’t uncommon (see “Is my bump wise to the world?“). Perhaps the best illustration of this is that we tend to be more tolerant of spicy food if our pregnant mothers ate a diet full of such cuisine.

Likewise, Konstantinos Fegeros’s team at the Agricultural University of Athens in Greece has shown that if a pregnant sheep is fed oregano, after birth its lamb is more likely to choose food flavoured with the herb than if its mother is fed a regular diet.

Even chicken fetuses locked away inside eggshells get a dose of their mothers’ diet. Aline Bertin