Nearly 500 million years ago, during the Cambrian period, the ocean teemed with various arthropods, some of which were different from the marine creatures we see today. One such arthropod was Selkirkia, a creature with protective gills that it used to construct its own burrows. Its body was covered in scales, carapaces, and spines, serving as defense against predators. In recent research conducted by NPR, scientists have managed to recover well-preserved remains of these ancient arthropods on Earth’s surface.

Dr. Karma Nanglun, a paleontologist from Harvard University, and Xavier Ortiga-Erandesha examined newly found fossil specimens of Selkirkia, extracted from sedimentary rocks dating back 500 million years. These fossils have provided valuable insights into the size of these creatures, which measured about one centimeter long. Nanglun explains that compared to other arthropods from that period, these creatures were relatively small. However, their burrows offered them a safe haven from their surroundings, making them quite comfortable in their sedimentary abodes.

In the past, it was believed that Selkirkia emerged around 475 million years ago. However, according to a study published in Biology Letters, Nanglun and Ortiga-Erandesha’s research suggests that their existence predates this estimation by more than 25 million years. This fascinating discovery challenges the conventional understanding of geological and evolutionary eras, indicating that these boundaries may not be as well-defined as previously thought.