Dinosaurs were still thriving just before asteroid hit: Study

Evidence from fossil site contradicts idea that creatures were in midst of worldwide decline

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A fossil site in New Mexico with numerous dinosaurs, including the gargantuan Alamosaurus, dates to just before the asteroid strike that abruptly ended the age of dinosaurs, according to research highlighting that these creatures were still thriving on the eve of destruction.

Palaeontologists have debated the age of fossils found at the Naashoibito site in northwestern New Mexico.

The new study used two methods to determine that the fossils date to roughly 340,000 years - a blink of an eye in geological time before the asteroid hit off the coast of Mexico's Yucatan Peninsula 66 million years ago at the end of the Cretaceous Period.

The calamity erased three-quarters of the earth’s species, including all the dinosaurs aside from their bird descendants.

One of the dating techniques was based on the direction of the earth’s magnetic field at the time, as recorded in Naashoibito rock.

The other involved measuring the decay of naturally occurring radioactive isotopes, or forms of elements, in sand grains embedded in rock at the site.