17 April 2018: Dinosaurs Ended, And Started, With a Bang

In the news today: the dinosaurs in the UK government struggle with the notion of decency, and the dinosaurs in the American government struggle with the notion of honesty.

Which is why it’s best to turn off the radio, put down the newspaper, log off the computer and give the phone to the dog to play with for a while. Here’s a science story about actual dinosaurs.

Before they were wiped out by a meteor, Dinosaurs ruled the earth for over a hundred and fifty million years,. The footprints they left behind show that their ecological dominance across the world may also have been due to a major extinction event.

During the Jurassic and Cretaceous periods, dinosaurs flourished across every continent on earth, from enormous herbivores, to ferocious raptors, to tiny bird-like therapods. And while the catastrophic cau se of their demise is widely accepted, exactly how dinosaurs became so dominant, comprising over 90% of the fauna in some regions, has been unclear.

In a study published in Nature Communications this week, researchers from the University of Bristol in the UK and the Universities of Padova and Ferrara in Italy believe they have found the answer in the footprints dinosaurs left behind.

The researchers examined dinosaur footprints in rock strata in the Dolomites, a mountain range in Northern Italy. In rocks dated to be over 200 million years old, they found only a small number and diversity of footprints, showing that dinosaurs existed at that time in the early Triassic, but comprised less than 5% of the fauna.

Following a succession of rock strata, the scientists then found evidence for a period of dramatic climate upheaval known as the Carnian Pluvial Episode, or CPE, around 230 million years ago. During the CPE the climate shifted from arid to humid and back again several times in just a million years or so, and a large number of the world’s animal species became extinct as a result.

In the rocks dated after this period, the researchers found a sudden explosion of dinosaur footprints or all shapes and sizes. They conclude that the CPE extinction event left behind a wide array of ecological niches that dinosaurs quickly exploited, spreading and diversifying to become the dominant animals across the globe.

The results agree with evidence from dinosaur fossils in Argentina and Brazil, which show an explosion in diversity around the same period.

These findings show that the age of the dinosaurs may have started and ended with a bang.

Original Paper: https://www.nature.com/articles/s41467-018-03996-1