Giant prehistoric sea monster found in one of driest places on Earth

By Mark Waghorn via SWNS

A giant prehistoric sea monster found in one of the driest places on Earth shows how quickly the species evolved in size, scientists have revealed.

The gigantic creature lived 244 million years ago when the US was covered by a vast ocean.

It was at least 60 feet from nose to tail and weighed more than 40 tons - rivaling today's biggest whales.

Named Cymbospondylus youngorum, it belonged to a group of aquatic reptiles known as ichthyosaurs.

The discovery in Nevada's Black Rock desert shows how quickly they evolved. Its oldest ancestor emerged only 2.5 million years earlier - and was about three feet long.

The phenomenon has implications for climate change. Whales and sharks are not "guaranteed features of marine ecosystems," say scientists.

Lead author Professor Martin Sander, of the University of Bonn, Germany, said Cymbospondylus had a long snout with pointed teeth.

He explained: "It suggests a generalist diet of fish and squid - as inferred for most ichthyosaurs from teeth and stomach contents.

"Considering its size, C. youngorum could also have preyed on smaller and juvenile marine reptiles."

The animal was identified from its remarkably preserved skull - which alone measured more than six feet in length.

It was dug up in a remote area of treeless mountains, rugged canyons and dry lake beds.

Ichthyosaurs appeared in the oceans after the Permian mass extinction 252 million years ago.

They had fish-like bodies similar to tuna but breathed air like dolphins and whales. The apex predators were the Great White sharks of their day.

Prof Sander said: "Although whales are now the largest of Earth's creatures, they were not the first ocean giants to ply the seas."

Cymbospondylus was "exceptionally large" - hinting at an early and rapid burst in the evolution of extreme body size in Mesozoic oceans.

Prof Sander said: "It took whales about 90 percent of their 55 million-year history to evolve into the ocean giants we know today.

"Ichthyosaurs evolved to similar sizes in the first one percent of their 150 million-year history on Earth."

The findings in the journal Science suggest marine food webs during the Triassic could support such massive creatures.

Prof Sander said: "Ichthyosaurs were among the first vertebrates to thrive in the oceans after the Permian extinction."

They were wiped out by climate change about 90 million years ago - having ruled the oceans during the age of the dinosaurs.

Prof Sander said: "They persisted through most of the Mesozoic which lasted from 250 million to 66 million years ago.

"What makes Cymbospondylus more notable is the species' age. It evolved merely 2.5 million years after the appearance of the oldest proposed ichthyosaur relative and at most eight million years after the emergence of the group."

Dr. Lene Delsett and Dr. Nicholas Pyenson, of the Smithsonian National Museum of Natural History, Washington DC, said it provides lessons for today.

The researchers, who were not involved in the study, said: "Ichthyosaur history tells us ocean giants are not guaranteed features of marine ecosystems.

"It is a valuable lesson for all of us in the Anthropocene, especially if we want to sustain the presence of the surviving ocean giants among us that contribute to our own well-being."

The Anthropocene dates from the commencement of significant human impact on Earth's geology and ecosystems.

Scientists say a sixth mass extinction is already underway owing to manmade climate change.