These Are the Oldest Known Footprints on the Planet
https://gizmodo.com/these-are-the-oldest-known-footprints-on-the-planet-1826648702
An international team of researchers is claiming to have discovered the worlds oldest footprints. Dating back a whopping 550 million years and found in a limestone bed in China, the prints were made by an unknown sea creature that was undoubtedly very strange.
Fossils from the Ediacaran Period, sometimes called the Vendian Period, are exceptionally rare. The few animals that lived during this bygone era, between 635 million and 541 million years ago, were exclusively soft shelled, featuring no bones, teeth, or hard shells. Soft tissues arent prone to fossilization, since they degrade quickly after death, so scientists have only a shady conception of what some of our planets earliest animals were like.
The Ediacaran was the period immediately before the Cambrian Explosion (541 million to 510 million years ago), a time when life underwent rapid diversification. But aside from bacteria and green algae, there were some animals of note from the Ediacaran Period. Some of Earths first burrowing creatures emerged during this time, as evidenced by the fossilized burrows themselves. As to what the creatures that dug these holes looked like, we can only guess. That said, paleontologists have found slither marks etched onto the surfaces of ancient rock, a hint that worm-like animals were slithering and burrowing so very long ago.
Clearly, complex animals were starting to emerge during the Ediacaran Period, including animals with symmetrical body plans. Known as bilaterian organisms, these animals featured a head, tail, back, and stomach. And for some, a symmetrical body also involved paired sets of appendages. New research published this week in Science Advances reveals the fossilized footprints left by one of these early creatures, and its considered the oldest known trackway made by a bilaterian creature with paired appendages.
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