Riley Black - The Last Days of the Dinosaurs

The odd thing about dinosaurs is that they are defined by their absence. As children we learn about these enormous creatures that no longer exists, and perhaps our fascination with them stems from their extinction. Like mythical dragons they do not exist, but at the same time dinosaurs are not dragons - they did once roam the Earth, and then they were gone. 

But the strange thing is that while dinosaurs are known by extinction, we discuss the actual extinction very little. What usually matters for enthusiasts is dinosaur life. Museums don't have dioramas depicting mass death - we see replica dinosaur standing in landscapes. But the manner of extinction does matter, not least because we are living through an era of extinction ourselves. So Riley Black's book is unique because it looks precisely at the end of the dinosaurs - the moment of transition from Cretaceous to Paleocene. What exactly happened when that asteroid hit? 

While this is a book seeped in science Black tells the story as a narrative. She begins with a typical dinosaur diorama in Hell's Creek (now in Montana) reconstructed from fossil evidence. In an opening chapter we follow a Triceratops which dies of old age, and see how scavenging animals wait patiently for a Tyrannosaurus rex to break open the tough armoured hide so they can feast too. It is a scene drawn from Black's own experiences in Yellowstone Park watching birds wait for a grizzly to open up a dead bison. 

Each chapter tells similar stories, introducing the reader to a variety of dinosaurs and animals, following them through the extinction, then exploring what Hell Creek looked like a day, a month, a year, one thousand years and one hundred thousand years after impact. It is a sobering read. I was struck by how quickly extinction took place - most of the dinosaurs on Earth were dead in the 24 hours after impact, killed by a infra-red pulse that raised temperatures so high that they simply could not survive. I was also struck by how lucky humans are - the evolutionary space created by the extinction gave mammals the space to evolve. But had events taken slight different turns - asteroid impact at a slightly different angle - dinosaurs might have survived. Or indeed the impact been so great that only bacteria survived and life began, so to speak, again. We would not be here.

It is a grim story, that Black tells well. In parts it is a horror story, "there is no dawn on the first day of the Paleocene" writes Black. We can imagine the suffering and pain that billions of creatures felt in the previous 24 hours, and we can imagine just how difficult life will be for the survivors. This is not the gradual dying off of previous "extinctions" or even that accelerated extinction that we're seeing today. This was a light going out.

While Black's book did make me draw connections with today, oddly they weren't just about extinction. What I was repeatedly struck by was the way their descriptions of dinosaur ecology made me think about ecological relationships today. Black makes you think what a herd of massive dinosaurs does to the environment around them as they stomp through:

When ever-hungry Edmontosaurus and Ankylosaurus mowed down plants with their mouths, they shaped what would become of the forest. Young, juicy plants were always the best delicacy, so these dinosaurs often cropped off young plants before the could take hold. These megaherbivores kept the meadows and open ground clear, just as Triceratops did when they'd rub their horns against trees to the point of toppling some over. Soil  was packed, seeds were scattered ,carcasses were left behind to nourish the soil... And vast quantities of dung... Dinosaurs did not merely inhabit the world as if it were a ready-made diorama. Dinosaurs literally made the world their own.

What is true of dinosaurs is also true of the world today. Species make their own nature, shape their own ecology which in turn shapes them. Similarly, Black shows how evolution fits the context in which it takes place. There is no preordained path, rather "each evolutionary happenstance opened up new possibilities, biodiversity generating itself through interaction". Not all the animals that survived made it. Not all the lineages developed and not all the ecological niches were filled.

While fresh, readable and packed with information this is a book that is rooted in contemporary science. I read each "narrative" chapter and then the corresponding section of the appendix where Black tells us precisely what bit of science backs up the descriptions she's made, and indeed the places were she has had to extrapolate or make educated guesses. I suggest that if you read it you do likewise.

This remarkably accessible book is well worth a read. Riley Black's Last Days of the Dinosaurs is very likely to be my science book of the year, and I hope that others grab hold of it. While the central events of the story are 66 million years ago, the connections I made were very contemporary. Highly recommended.

Related Reviews

Kolbert - The Sixth Extinction: An Unnatural History
Gould - Wonderful Life: The Burgess Shale and the Nature of History
Fortey - Survivors: The Animals and Plants that Time has Left Behind
Fortey - Trilobite! Eyewitness to Evolution
Ward - The Call of Distant Mammoths: Why the Ice Age Mammals Disappeared
Tudge - The Secret Life of Birds
Maddox - Reading the Rocks
Cadbury - The Dinosaur Hunters