Mysterious Leaf-Like Creatures May Have Been Among Earth's First Animals

Unusual Ediacaran organisms preserved as fossils dating back more than 500 million years have been a source of mystery for decades, but science may finally have an answer, according to new research out of the Tokyo Institute of Technology, the University of Cambridge, and Northwest University. A study newly published in the journal Paleontology details these fossilized organisms, revealing that they may have been animals.

Ediacaran organisms were first discovered in the mid-1940s in Ediacara Hills, South Australia, hence the name. In the decades since, scientists have discovered around 200 different varieties of these organisms preserved in ancient rocks, but questions remain over whether they were a type of fungus, algae, or something else.

No such organisms remain on Earth — they died out around 541 million years ago. More recently discovered fossils may solve the puzzle, according to the newly published study, which reveals that 206 new fossils featuring Stromatoveris psygmoglena have been found. These fossils date back to around 518 million years ago and show the preserved imprint of an ancient, tiny marine animal.

The new study points toward these fossils as showcasing an Ediacaran organism that managed to survive longer than the rest, passing on into the Cambrian period. Talking to Science Mag, one of the researchers behind the paper, Jennifer Hoyal Cuthill, noted that the Stromatoveris fossils has features similar to Ediacaran organisms.

Via computer analysis, the team found that Ediacaran organisms including Stromatoveris don't belong with any existing animal phylum, instead having their own little pocket on the evolutionary tree. The creatures fall between complex animals (like worms) and sponges. The link, Science Mag notes, does raise a new question: what caused their extinction?

SOURCE: Science Mag

Image by J. Hoyal Cuthill via Science Mag