How asteroids smashed Earth to let life grow

AS the dinosaurs found out to their cost, a massive asteroid smashing into the planet is not a desirable event.

But now scientists have shed further light on how such Earth-shattering impacts allowed the extinct beasts – and all life as we know it – to evolve in the first place.

They believe the asteroids that bombarded the Earth around six billion years ago helped smash the planet’s granite surface into a more porous kind of rock suitable for the growth of organisms.

The conclusion is based on research at the best remaining example an early deep-impact crater, at Chicxulub in Mexico.

This is the location of the asteroid that wiped out 75 per cent of life on Earth – including the dinosaurs – 65million years ago.

An international team studying the crater – much of which is under water in the Gulf of Mexico – drilled nearly a mile into the sea floor to examine rock samples.

They found the asteroid impact made the rocks more porous and less dense, providing niches for simple organisms to take hold with the help of nutrients from water heated inside the Earth’s crust.

Professor Joanna Morgan, lead author of the study from Imperial College London, said: ‘It is hard to believe that the same forces that destroyed the dinosaurs may have also played a part, much earlier on in Earth’s history, in providing the first refuges for early life on the planet.’