Hairs’-width ‘dream fossil’ is earliest non-blob creature found

At a quarry in southern China, researchers have discovered the oldest known ancestor of all creatures that have a left and a right, a front and a back, a top and a bottom.

A team of paleontologists from the University of Southern California, the California Institute of Technology and the Nanjing Institute of Geology and Paleontology in China found fossils of a 580-million-year-old microscopic creature believed to be the earliest known example of a bilateral body form – an animal with a complex, purposeful shape, unlike the animated blobs that preceded it.

The specimens could be souvenirs from the start of one of life’s most successful experiments, when creatures first developed the anatomical symmetry that defines almost all modern life forms, including humans, experts at the University of California, Berkeley and Dartmouth College said.

“It is the dream fossil, in a way,” said Duke University evolutionary biologist Gregory Wray.

Each of the 10 oval-shaped microorganisms is no more than the width of four human hairs laid side by side, yet is surprisingly complex, the researchers said in work published online this week by Science Express.

The symmetrical anatomy of V. guizhouena suggests that the creature could direct its own movements, either in pursuit of prey or to flee larger predators, rather than drifting on currents or clinging to one rock, said USC earth sciences researcher David Bottjer, one of the study’s lead scientists.

“This is evolution on a very grand scale,” Bottjer said.