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# The butterflies that came back to the boy
- URL: https://www.earthtoseanews.com/butterfly-boy/
- Published: 2026-08-15T20:00:00.000Z
- Updated: 2026-08-21T08:06:08.000Z
- Description: A ten year old in Kobe wondered if his butterflies remembered him. The answer is now heading for a science journal.
- Author: Nicole McMahon
- Tags: Global Good News, All stories, Rewilding

Jo Nagai, ten years old, of Kobe, Japan, raises swallowtail caterpillars at home, feeds them, cleans up after them, and lets them go when their wings are ready. Except his butterflies kept not quite going: they lingered at the release, and some flew back to him. So he asked the question every scientist starts with: does a butterfly remember being a caterpillar? He found the one person on Earth most likely to know, Dr. Martha Weiss of Georgetown University, whose famous study first showed that moths can carry caterpillar memories through metamorphosis, and he wrote to her.

What followed was a years long correspondence across continents that turned into a genuine collaboration. With her guidance, Jo ran his own version of the memory experiment at home using a lavender scent, and eight out of ten of his butterflies remembered their caterpillar lessons on the wing. Boy and professor will now present the findings to the Journal of the Lepidopterists' Society, and his next question is already chosen: can a butterfly pass a memory to its young? Dr. Weiss puts it simply: he is a real scientist, and he is figuring out new stuff.

Our short take: the full story is by Meghan Cook for Good Good Good, July 2026\. Cover photograph: a swallowtail butterfly in Itami, Japan, by Culturegeeks, [CC BY-SA 4.0](https://creativecommons.org/licenses/by-sa/4.0?ref=earthtoseanews.com), via Wikimedia Commons.