Our earliest vertebrate ancestors had something special—four eyes! Fossils from China show that jawless fish, dating back about 518 million years, had two pairs of eyes. These ancient creatures, known as myllokunmingids, used their extra vision to survive in a perilous environment.
Researchers recently unveiled a cute reconstruction of these fish. Picture them swimming with large eyes on either side of their heads and smaller eyes right in the middle. This unique setup might have given them a wider view, helping them dodge predators lurking in the ocean.
Jakob Vinther, a macroevolution expert from the University of Bristol, says this discovery shifts our understanding of vertebrate evolution. “These animals were more visually sophisticated than we thought, adapting to a dangerous world,” he explains. This insight helps us see our own journey, as we are distant relatives of these nifty fish.
During the Cambrian period, when these fish lived, many large predators emerged. As a result, myllokunmingids relied on their advanced eyesight for safety. Fortunately, fossils found in China provided detailed glimpses of their eyes. The rare discoveries were made in the Chengjiang fossil beds, known for preserving soft tissues like eyes that are typically lost to time.
Peiyun Cong, a paleobiology researcher at Yunnan University, expressed excitement about uncovering the smaller eyes. “We were amazed to find fully functional eyes between the larger ones,” he shared. These findings show that the smaller pair had the ability to process images, hinting at the evolutionary path of eye-like features we see in some modern vertebrates.
Interestingly, some current fish, reptiles, and amphibians have a “third eye,” known as the parietal eye, which detects light. This feature is connected to the pineal gland in humans, responsible for producing melatonin that aids sleep. Vinther notes that myllokunmingids used their two additional eyes for survival, while their descendants now use similar structures to regulate sleep patterns. “What we’re seeing is that the pineal organs began as image-forming eyes,” he added.
These discoveries remind us of an ancient world where vision was key for survival. They also provide fascinating insights into how creatures evolve over time, shaping traits we still see today. Our connection to these ancient fish shows that every new finding takes us one step closer to understanding our own history in this vast web of life.
