Fossil Wiki:Featured articles/Kimberella



Kimberella is a genus of disputable multicellular organism known from fossils that date back to the Ediacaran period, and only one species, K. quadrata, has been recognized. Specimens were first found in Australia's Ediacara Hills, but recent research has concentrated on the numerous finds near the White Sea in Russia, which cover an interval of time from 555-558 Ma. As with many fossils from this time, its evolutionary relationships to other organisms is hotly debated. Paleontologists initially classified Kimberella as a type of jellyfish, but since 1997 features of its anatomy and its association with scratch marks resembling those made by a radula have been interpreted as signs that it may have been a mollusc. Although some paleontologists dispute its classification as a mollusc, it is generally accepted as being at least a bilaterian. The classification of Kimberella is important for scientific understanding of the Cambrian explosion: if it was a mollusc or at least a protostome, the protostome and deuterostome lineages must have diverged significantly before 555 Ma. Even if it was a bilaterian but not a mollusc, its age would indicate that animals were diversifying well before the start of the Cambrian. (Read more...)