Thursday, 5 April 2012

Fire And Dinosaur Remains

Carbonized wood with a light growth of quartz crystals
The Cretaceous was the last great time period in the Mesozoic era. It oversaw many incredibly evolutionary events from the rise of the last group of giant dinosaurs, the titanosaurs, to the evolution of modern mammals. It was also a dangerous time to live. The continents split up, volcanoes and earthquakes were common, alongside eruptions of toxic gas. The Cretaceous ended when 70% of life was destroyed on Earth, including the dinosaurs, by a meteorite.

Geologists and palaeontologists studying fossiliferous localities across the globe believe that the last creatures of the Mesozoic also had giant forest fires to contend with. Oxygen levels and temperatures were higher, resulting in a deadly combination of flammable gas and dry, plentiful fuel. Lightning strikes were the trigger. This theory of giant wild-fires is one which has been put forward before, but now there is geological evidence to back it up.

'Charcoal is the remnant of the plants that were burnt and is easily preserved in the fossil record' said study researcher Andrew C. Scott, a professor from Royal Holloway University of London. By using a database of these deposits, geologists have found that they exist on a global scale and are often associated with beds of Cretaceous dinosaur remains. These come from the same geological layers, and are so close geographically, that they must be linked.

The researchers concluded that the charcoal beds were the result of vast forest fires in which many creatures perished. The animal world was badly affected each time yet the plants fared better. While they were temporarily destroyed, their carbonized remains enriched the soil beneath, allowing the forests to return bigger than before to support increasingly larger ecosystems.