WASHINGTON : It was a dire moment for life on Earth. Runaway global warming triggered by calamitous volcanism in Siberia inflicted the worst mass extinction on record - dooming perhaps 90 per cent of species - roughly 252 million years ago at the end of the Permian Period.
The fossils suggest that Inostrancevia left its place of origin and trekked over time - maybe hundreds or thousands of years - about 7,000 miles across Earth's ancient supercontinent Pangaea at a time when today's continents were united. Inostrancevia filled the ecological niche of top predator in South Africa left vacant after four other species already had vanished.
Inostrancevia is part of an assemblage of animals called protomammals that combined reptile-like and mammal-like features. It was 10-13 feet long, roughly the size of a Siberian tiger, but with a proportionally larger and elongated skull as well as enormous, blade-like canine teeth.