Dinosaurs may have survived had the asteroid that struck Earth been off by just a few million years, scientists now claim, with "colossal bad luck" blamed for their extinction. The six mile wide space rock struck the planet arrived at just the wrong time, researchers at the University of Edinburgh say, combining with existing environmental changes on Earth that added up to dinosaur disaster.
"The dinosaurs were victims of colossal bad luck," Dr Steve Brusatte of the School of GeoSciences said of the new findings.
By sifting through the latest dinosaur fossils, the palaeontologists examined how the asteroid strike might have impacted factors like food availability. The belief now is that diversity among the food chain was relatively low, because herbivore dinosaurs were struggling.
Higher than normal volcanic activity, temperature fluctuations, and changes in sea level are all cited as contributing to lower plant life levels.
"Not only did a giant asteroid strike, but it happened at the worst possible time, when their ecosystems were vulnerable" Dr Steve Brusatte
With herbivores struggling, and the asteroid itself introducing further earthquakes, rapid temperature swings, tsunamis, and sweeping fires, different stages of the food chain would have been progressively wiped out, the research team concludes.
However, it could have been very different had the timing been off by even just a few million years in either direction.
For instance, if it had struck earlier, although the environmental impact would have still been huge, dinosaur species would have been more diverse. A more stable supply of food would thus have meant a greater likelihood of dinosaurs other than flying species surviving.
Had the meteor hit later on, meanwhile, different species may have had time to evolve to better deal with the pre-existing conditions on Earth. They would have been "very likely" to survive, the scientists say.
Exactly how long dinosaurs could have expected to have lived on even if the timing had been more favorable is unclear, and the University of Edinburgh team plans to do further research on fossils in Spain and China to get a broader understanding of the events 66 million years ago.
SOURCE University of Edinburgh