Fish

A 67-million-year-old fossil fish discovered in Alberta, Canada, has led UC Berkeley researchers to revise the evolutionary timeline of otophysan fish, revealing that their advanced hearing system developed in the ocean before two separate migrations to freshwater. This group, which includes over 10,000 species like catfish and zebrafish, evolved sensitive ears rivaling human hearing capabilities. The findings challenge long-held assumptions about their origins.

October 05, 2025 由 AI 报道

A tiny fossil fish discovered in southwestern Alberta is the oldest North American otophysan, offering new insights into the evolution of freshwater fish species. Named Acronichthys maccognoi, the 4 cm specimen from the Late Cretaceous period suggests otophysans transitioned from marine to freshwater environments at least twice. The find, detailed in a study published on October 2 in Science, challenges previous understandings of their global spread.