Unique vine ‘greenhouses’ found by 91-year-old nature volunteer

An unusual vine discovered by a 91-year-old volunteer nature guide in Japan has a “unique” way of using its leaves to curl around its fruits to envelop them in a protective microclimate, scientists said on Wednesday.

The cucurbitaceous vine, a type found in East Asia, is an oddity because while leaves come in all shapes and sizes and perform a crucial role in photosynthesis, they are rarely associated with reproduction. But a new study published in the journal Proceedings of the Royal Society B: Biological Sciences found that the vine had specialized leaves able to enclose fruit and enhance seed production in colder conditions.

The research was co-authored by Nobuyuki Nagaoka, the 91-year-old guide at Yamagata Prefectural Natural Museum Park, who first spotted the leaf behavior in 2008 and has observed it every autumn since. Intrigued by the strange leaf “greenhouses”, he looked online for information about the vine, said co-author of the study Shoko Sakai, a professor at the Center for Ecological Research at Kyoto University.

“Our newsletter published in 1998 had an article about this plant. He saw the article and sent me a letter in 2008,” Sakai told AFP. He said initially when he saw a picture of the leaf enclosure he thought “it was a maldeveloped or pest-infected shoot”. But “when we read subsequent observation records he sent to us, it became clear that this was an interesting phenomenon worth further investigation,” he said, adding that it was only when the researchers examined the real thing that they could confirm what it was. “When I saw it, I was excited to find out that they were indeed leaves,” Sakai said.