Ancient Mussel Fossil Reveals 125-Million-Year-Old Maternal Care

A 125-million-year-old fossil of a freshwater mussel (Margaritifera valdensis) from the Isle of Wight preserves soft tissues and developing young inside a brood chamber, yielding the earliest fossil evidence of parental care in shellfish. The reproduction involves eggs fertilized in gills with larvae that later infect fish, shedding light on ancient reproductive strategies and mollusk evolution, while underscoring threats facing modern freshwater mollusks.