The hydra is a favorite subject of middle school science. It is a fearsome-looking tentacled predator, but it is tiny — less than a half inch — and lives in ponds. Adult, professional scientists are interested in them, too, particularly the way a hydra snippet grows up.
"How a Scrap of Hydra Regrows a Whole Animal" is from the February 13, 2017 Science section of The New York Times. It was written by James Gorman and narrated by Fleet Cooper.