Ancient seafloor creature grew like modern invertebrates

Researchers have found that an ancient seafloor creature, Parvancorina minchami, grew much like modern marine animals. This small, anchor-shaped creature lived around 550 million years ago. It is similar in growth and lifespan to current marine invertebrates, such as golden shrimp and Baltic clam. The study, conducted by teams from the Russian Academy of Sciences, Harvard University, and the University of British Columbia, reveals that P. minchami lived for about four years and could grow up to nearly 20 millimeters in length. The pace of its growth was comparable to that of small, modern invertebrates. Dr. Andrey Ivantsov, the lead author, noted that these findings help researchers understand the roles of early multicellular animals in ancient ecosystems. The study was published in the journal Paleobiology. The Ediacaran period, before the Cambrian, is known for the emergence of early animals. A significant fossil site in the White Sea region of Russia preserved hundreds of specimens of P. minchami. Researchers analyzed 211 fossils classified by size to determine growth patterns. They applied a software tool called Electronic Length-Frequency Analysis (ELEFAN) to estimate the growth rates and lifespan of these ancient creatures. This method, developed in the 1980s, helped bridge the knowledge of modern marine growth dynamics with that of the fossils. Dr. Daniel Pauly, a principal investigator in the study, emphasized the importance of this type of analysis in understanding the biology of ancient animals. Co-author Dr. Andrew Knoll noted that although these early fossils may look strange, such studies relate them more closely to known animals.