Child Prodigy Discovers Butterflies Remember Caterpillar Life, And Pass Down Memories To Offspring

March 18, 2026

At just 10 years old, Jo Nagai conducted an experiment that would surprise scientists around the world.

By raising and training swallowtail caterpillars at home, Jo demonstrated that butterflies can retain memories formed during their larval stage, even after undergoing complete metamorphosis.

But what he discovered next was even more unexpected: those learned responses appeared to persist to the next generation.

Metamorphosis is one of the most dramatic transformations in nature. A caterpillar essentially dissolves and rebuilds itself inside the chrysalis, emerging as a completely different creature.

It seemed logical that any memories would be wiped away in the process.

But Jo's research told a different story.

In the study, caterpillars were trained to associate a specific scent with an unpleasant experience. Later, after they had transformed into butterflies, researchers tested whether they still reacted to that same smell.

Surprisingly, many of the butterflies avoided it.

That reaction suggests something incredible—that memories formed during the caterpillar stage can survive the transformation into a butterfly.

And then he took it even further.

Journalist Annie Rosenthal, whose mother is Martha Weiss, an esteemed entomologist, shared that his research also suggested caterpillars can pass memories down to their offspring.

"He did his experiment again, but tested a second generation too, to see if they avoided the same smell he'd trained their parents to hate. And a few months later, he wrote to my mom that the results were clear. His butterflies had passed their memories on to their children," Annie Rosenthal shared.

While butterflies aren’t consciously teaching their babies like humans do, this finding hints that life experiences from one generation can influence the next — a phenomenon scientists are exploring under the lens of epigenetics.

The video below gives a fascinating visual explanation of the experiments: