Though their wriggling, oozing forms may provoke a shudder, worms seem like uniquely fragile creatures—prone to getting flattened underfoot, flash-dried on a sidewalk, or crushed in the beaks of the early birds that patrol the dawn.

And yet, scientists have recently discovered one species of worm that would inspire the envy of any survivalist: It endured multiple mass extinction events across a half billion years without ever changing its lifestyle.

Karma Nanglu, a University of California, Riverside, paleobiologist, says she and her colleagues were studying ancient bivalves who lived hundreds of millions of years before the dinosaurs went extinct when they noticed a series of mysterious question mark shapes etched into the fossil shells.

They began asking themselves some questions about the traces of this symbol of inquiry, curiosity, and doubt.“It took us a while to figure out the mystery behind these peculiar-looking traces,” said Javier Ortega-Hernandez, a Harvard University evolutionary biologist, in a statement.

“It was as if they were taunting us with their question mark-like shape.” Ortega-Hernandez is a curator at the university’s Museum of Comparative Zoology, which houses the fossils studied by Nanglu’s team.

Source:Nautil