A large evolutionary study reveals that collective schooling is neither a rare innovation nor an irreversible evolutionary achievement.
Researchers combined machine learning, scientific descriptions and citizen-science imagery to investigate schooling across 2,839 fish species. Their analysis suggests collective movement evolved independently approximately 60 times and was lost approximately 320 times over 350 million years. Schooling was associated with predator avoidance, ecological relationships and greater evolutionary diversification, but researchers also identified possible disadvantages, including competition, disease exposure and the propagation of false alarms. The findings challenge assumptions that collective organisation is invariably advantageous.
https://phys.org/news/2026-11-machine-reveals-fish-schooling-evolved.html
