Enigmatic Horodyskia williamsi from Precambrian Australia

Description: Some 30 years ago the late Robert J Horodyski discovered what he termed “problematic bedding plane markings” in Precambrian deposits in Glacier National Park of Montana. These were later found to be the remains of what are currently the oldest known multicellular organisms named Horodyskia moniliformis in his honor. In addition to those found at Glacier National Park, this species found in Australia is also known to science. Horodyski called them a string of beads” a most apt description. They appear to have been attached by a stolon (the “string”) and had a regular position along the chain. Given the presumed nutrient-poor water in which they lived they are thought to have been photosynthetic lake the stromatolites. Horodyskia williamsi is currently believed to be the earliest of multicellular organisms to have colonized the planet.

Reference: Smithsonian Institution Press Contributions to Paleontology, no 94, 202.