Mystery Solved as to Why Algae Balls Float, Sink

"Unfortunately, marimo balls are endangered, being currently found in only half the lakes where they were once spotted," Dora Cano-Ramirez, Ph.D. student and lead author of the study, said. Takuya Kawakami, a Japanese botanist from the Sapporo Agricultural College (now Hokkaido University) first discovered the green algae aggregates in the bay of Lake Akan and named them "marimo" in 1897. Due to its beauty and critically-endangered status, Marimo has been used as an environmental education tool and is subject of a three-day annual festival by the Ainu people in Hokkaido, where marimo is welcomed at the beginning of the festivities and returned to the lake at the end in a sacred ceremony.