A team of researchers from Yunnan University in China, along with partners from the UK’s University of Leicester and University of Bristol, has made a remarkable discovery of rare fossils belonging to a jawless fish family known as Myllokunmingia, dating back approximately 518 million years to the Cambrian period. This fascinating species exhibits a unique anatomical trait of possessing four eyes: two pairs on the sides of its head similar to most contemporary animals and a smaller pair situated in the center of its head.

The researchers unearthed two distinct types of these Myllokunmingia fossils from the fossil sites in the Yunnan province of southwest China. One of the species has been identified and named Hatikweikithys erkaikonenensis, while the other remains unnamed at this time. By employing advanced microscopy and chemical analysis methods, the study, published in the journal Nature, reveals that the smaller eyes were fully functional rather than mere light-sensitive spots, providing insight into the evolutionary adaptations of early vertebrates.

This discovery highlights the complexity of the anatomical structures present in ancient life forms and their potential adaptive significance during the Cambrian explosion, a time known for the rapid emergence of diverse life forms. Furthermore, it opens up new avenues for studying the evolutionary history of vertebrates and the development of sensory organs, underscoring the rich biodiversity that once existed in prehistoric ecosystems.