Earliest Jurassic corals discovered

In the dusty, high desert of central Nevada, a team of researchers from University of Montana has found the fossil record of the earliest North American coral species that reappeared after the Triassic-Jurassic mass extinction event.

Five times in Earth's history mass extinction events have wiped out up to 90 percent of global life.

Corals are particularly hard-hit by subtle changes in ocean temperature and acidity. About 200 million years ago, corals and reefs completely collapsed.

After that mass extinction event, it took coral reefs more than 20 million years to completely recover.

The fossils left in the rocks of central Nevada offer a fairly complete snapshot of the mass extinction. Yet, the significance of the corals found there had not been noted until now, the study said.

"The Jurassic corals represent a recovery of all species after the event," said Montana Hodges, doctoral student at University of Montana in the US.

"They are simple, solitary corals that lived in thick mud, which may have helped their survival during such a tumultuous time. Or they may have migrated from the distant side of Pangea," Hodges noted.

Regardless, they are the earliest representatives of the coral that would slowly rebuild and diversify over millions of years.

By studying these unique corals, the researchers hope to contribute to a better understanding of survival and recovery of corals.

"Our study may lend valuable information to understanding the peril of coral reefs today," Hodges said.

The findings appeared in the new magazine GSA Today, a publication of the Geological Society of America.