小学生の研究が米学術誌に　「カブトムシは夜行性」の常識覆す

　「カブトムシは夜行性」との常識を覆し、特定の木で昼間も活動することがあるとの研究結果を、埼玉県の小学６年柴田亮さん（１１）が導き出した。２年かけて自宅の庭木に昼も集まるカブトムシを観察しデータを収集。成果が米国の生態学専門誌「エコロジー」に掲載される快挙となった。
　柴田さんは２０１９年夏、自宅庭のシマトネリコの木にカブトムシが日中も現れることを不思議に思い、研究を始めた。毎日庭木を観察し、集まったカブトムシに印を付けて個体を識別。２０年は計１６２匹を観察し、活動パターンや時間帯ごとの数などを詳しくまとめた。
　調査には山口大理学部の小島渉講師も関わった。１９年夏に「自由研究を見てほしい」という連絡を受けたのを機に指導を開始。小島講師は「私はアドバイスと翻訳をした程度で、ほとんど柴田さんが主体の研究。完成度はかなり高い」と評価し、今後も一緒に調査を続けるという。（2021/05/04-15:58）

A research outcome obtained by an 11-year-old Japanese boy has been published on the U.S. journal Ecology, defying the common wisdom that beetles are active only at night.
   Ryo Shibata from Saitama Prefecture, north of Tokyo, observed beetles which gather during daytime at an evergreen ash tree, or Fraxinus griffithii, planted in the yard of his house, and collected related data over two years.
   The elementary school sixth grader started his research in summer 2019, as he wondered why beetles come to the tree during the day.
   He checked the tree every day, putting marks on the beetles gathered there so that they could be identified individually. In 2020, he observed a total of 162 beetles and compiled data mainly on their activity patterns.
   Wataru Kojima, a lecturer at Yamaguchi University's Faculty of Science in the western Japan prefecture of Yamaguchi, helped Shibata's research. He began to offer support after the boy asked him to check his school assignment in summer 2019.