اكتشاف أحفوري مذهل يتحدى أصول الحياة الحيوانية

Scientists revisiting mysterious 540-million-year-old microfossils from Brazil have overturned a major idea about early animal life. What were once thought to be trails left behind by tiny worm-like creatures are now believed to be fossilized communities of bacteria and algae — some with remarkably preserved cells and organic material still intact.