The association between the end of the age of dinosaurs and an asteroid impact off what is now Mexico is well evidenced. Their fossil evidece ends at the Cretaceous–Paleogene (K–Pg) boundary, formerly known as the Cretaceous–Tertiary (K-T) boundary. This is formed of material thrown high into the atmosphere by the hit. Diagnostic of the formation are tiny glass like balls of materials melted by the energy of the impact and raining down from on high.
There has never been published evidence of animals being killed by the impact — until now! For three years a BBC crew followed the excavation of a fossil deposit in Tanis, North Dakota. Robert DePalma, the University of Manchester, UK, graduate student who leads the Tanis dig believes they are the remains of animals deposited by tsunami after impact. Two fossils in particular show the violence of the event. A turtle had been skewered by wood. One fossil was a perfectly presrved dinosaur leg complete with skin that shows every evidence of being torn off by the water.
In the deposit was proof of the day of the cataclysm — throughout were those give-away glass balls. One even contained a piece which analysed as probably being from the asteriod itself.
The report on the dig is being presented to various learned societies. A documentary will be broadcast on BBC One on 15 April at 18:30 BST and on iPlayer after. A version has been made for the US science series Nova on the PBS network to be broadcast later in the year.
Please note: The top picture is of course an artistic impression. Neither the BBC nor the other great British institution Sir David Attenborough were around to film live in the age of dinosaurs. On the other hand, the BBC is celebrating its 100th year and Sir David first joined them, as a trainee TV producer, in 1952.