Dinosaurs: The Final Day with David Attenborough

*Dinosaurs: The Final Day with David Attenborough*
Dinosaurs: The Final Day with David Attenborough
Directed by	Matthew Thompson
Starring	BBC Studios Science Unit
Original release
Network	BBC One
Release	15 April 2022

Dinosaurs: The Final Day with David Attenborough (titled Dinosaur Apocalypse in the U.S.) is a British

Prehistoric Planet. Like that series, the programme's creatures were also made with computer-generated imagery.^[1]

In the United States, the documentary aired in a two-episode format for the PBS series NOVA - under the title Dinosaur Apocalypse - on 11 May 2022.^[2]

Synopsis

Using the Tanis fossil site in the Hell Creek Formation as evidence, Attenborough and paleontologists try to piece together the extinction of the dinosaurs and the asteroid believed to have killed them, 66 million years ago. At this site in North Dakota, numerous groundbreaking fossil discoveries that reveal information on the final years of the Cretaceous period and the organisms that were present during the time have been made.

On a spring morning, 66 million years ago, Tanis was a sandbank on the edge of a river near the

Tyrannosaurus rex tends to her eggs, and two Triceratops spar over territory in the woods just beyond the water's edge. Meanwhile, the river itself is full of a host of aquatic and semi-aquatic organisms, including baenid turtles, sturgeons, paddlefish and bowfins; plus Thescelosaurus, which uses the water as an advantage to escape bigger predators. Pediomys, a genus of early marsupial

mammal, also thrives at Tanis, though they spend much of their time burrowing and rushing through the undergrowth to avoid the other animals that make the sandbank their home.

Following the discovery of fossilised fish with

gill arches, insight into what destroyed the ecosystem at Tanis is made; the culprit, believed to be a seiche wave produced by seismic waves from the impact, must have arrived at Tanis while the spherules were still falling from the sky, up to two hours after the impact. A specimen of amber is found that contains an intact piece of tektite as an inclusion; analysis of the amber using the Diamond Light Source synchrotron in Oxfordshire yields the remarkable discovery of the spherule containing a piece of unmelted rock with quantities of metals that would be consistent with the Chicxulub asteroid itself. With a seiche

wave now believed to be responsible, a complete image of Tanis's final moments can be reconstructed.

Immediately after the asteroid struck the

Yucatan Peninsula

, life continued at Tanis as normal for several minutes. The blast generated by the impact would have been visible, but silent, as its shock wave dissipated a long distance away from Tanis. The effects of the impact arrived in the form of an onslaught of seismic waves and the rain of spherules that set the surrounding vegetation on fire. Shortly after this, a ten-metre high seiche is sent up the Interior Seaway, swiftly wiping out the area's ecosystem and preserving many different species beneath a layer of sediment that would eventually be unearthed by researchers as fossils in the present day. Two such fossils are discovered that give particular insight into Tanis's fate; a Thescelosaurus fossil is found with its skeleton in a jumbled state, suggesting it was killed by being thrown about by turbulent water, and a fossil of a turtle shows signs of the animal being impaled by airborne or waterborne debris.

In the hours that follow, heat given off by the impact ignites fires across the globe. Only the hardiest and most fortunate of the animals and plants can survive the relentless flames and smoke that enshroud the planet, giving rise to a

non-avian dinosaurs

, but not dinosaurs as a whole.