SATURDAY SUPPLEMENT: So how did these Dinosaurs really die?

News comes from Glasgow University this week that scientists have estimated the most accurate date yet regarding the extinction of the dinosaurs; some 66,038,000 years ago, give or take 11,000 years which might not appear that precise in the flesh, but then there are still some unanswered questions.

The date comes to us, the general public, after an intense debate regarding not exactly when the species died, but how. It's been suggested, furthermore, that a comet or asteroid crash-landed off the Yucaton Coast of Mexico and the crater produced was so large, (180km), that they've even named it: Chicxulub.

It seems that there's also a large crater in our understanding of this heated debate, and after ploughing through a couple of issues of the National Geographic from my collection, there's no wonder why. As the March 2003 issue states rightly, "the ultimate dinosaur behaviour was the act of going extinct. And the mystery of that event has hardly been solved." That was published exactly a decade ago, and despite developments this week, I don't think we've solved the puzzle yet. (I think we've only just took it out the box.)

In March 2003, there is a notion that the dinosaurs weren't necessarily the victim to an instantaneous outer-space collision such as a comet or asteroid, but to an extensively varied and accumulating range of "triggers", suggesting that any "big impact may have been the final blow". The article does lean towards the 'pathogen theory' remarking that at the end of the Cretaceous period, as "lands that were formerly separated by water were now connected...new species arrived, perhaps carrying deadly microbes". So was the greatest dying out spectacle of Earth induced by pathogens or by a deadly extra-terrestial blast? Both ideas have been seriously considered, and only ten years divide these schools of thoughts.

This week's report hints at a crater formation triggering the sudden decline of this empire, but this is no fresh theory. In the January 1993 National Geographic the article explains how "some scientists believed that a huge impact crater" (this time in Canada, not Mexico) "called Manicouagan explained the extinction". And still, even twenty years ago, this theory was argued. "Radiometric dating indicates the Manicouagan crater was formed several million years before the mass dying". "Some scientists argue that the extinction was probably the result of gradual climate change." (Is there anything that isn't blamed on climate change?)

Within twenty years, ideas have been floated, but nothing concrete has been set. Twenty years ago, hints at a Canadian Crater were passed off as chronologically inaccurate and in favour, the culprits were a number of differing climatic conditions. In 2003, this theory has flourished detailing possible micro-bacterial triggers. Yet, this week, ten years later, we've took the U Turn, and we're back to drawing crater holes and analysing asteroid geology. It's fantastic news that the most accurate date for extinction has been set. That will do for the gravestone. But what about the Coroner's report? Will we ever know what exactly killed the dinosaurs?