"The Rise and Fall of the Dinosaurs" by Steve Brusatte

Above: "The Rise and Fall of the Dinosaurs." Steve Brusatte. 349 Pages.

It appears that the Permian Extinction opened the way for a radical redirection of the evolutionary process to allow for Prorotodactylus, precursor to the dinosaurs.

I completed reading this book today.

Browsing recently through Sam Weller Bookstore at Trolley Square, Salt Lake City, I saw this book featured in the new books display. Given my growing interest... clumsily amateur to be sure...in paleontology, I thumbed the pages. It wasn't too long. It was written in very readable style and had plenty of pictures and easy to grasp charts and graphs. I decided to buy it.

My recently spurred interest in pre history and geologic time, started with motorcycle visits over the last two years to Fossil Butte (WY), Hagerman Fossil Bed (ID), and John Day Fossil Beds (OR) National Monuments.

I also recently read "The Sixth Extinction," by Elizabeth Kolbert. Sitting atop my pile of about twenty or so partially read books is New York Times bestseller, "Darwin's Doubt," by Stephen C. Meyer.

What a great experience I had reading this book! A lot of non-fiction books require (for me, at least) intense concentration, underscoring, slow, and deliberate perusal. This book reads like a fast paced adventure story and not a turgid text book.

Brusatte sets the stage for his dinosaur history by noting that the earth formed about 4.5 billion years ago. He notes how the first microscopic bacteria evolved a few hundred million years later. For some two billion years, earth was a bacterial world. About 1.8 billion years ago the simple, bacterial cells developed the ability to group together into larger, complex organisms.

540 million years ago came the well known Cambrian Explosion where skeletonized forms became abundant, started eating one another, and began forming complex ecosystems in the oceans.

390 million years ago, during the Permian, the first fishy creatures walked out of water on to land. By 251 million years ago, just prior to the Permian extinction, 252 million years ago, the world was full of amphibians and small reptiles.

There were many varieties of animals during the mid to late Permian, some over ten feet long and weighing over a ton.

There are no signs of dinosaur or crocodile tracks in the Permian layers, or even any tracks that look like precursors to these animals.

We know about the Permian animals.... from tracks. Permian animals didn't leave much in the way of fossils. Brusatte recounts his experiences in the Holy Cross Mountains of Poland with his Polish friend Grzegorz. Grzegorz was an expert in locating tracks in the Permian rock layers.

There are, however, no signs of dinosaur or crocodile tracks in the Permian rock layers, or even any tracks that look like precursors to these animals.

The Permian Extinction, 252 million years ago, was caused by the after effects (CO2 concentrations, temperature change, sea level change, methane concentrations) of a massive super volcano eruption in Siberia... similar to the now inactive (but not forever!) Yellowstone Caldera super volcano.

But, in looking at rocks at the Permian/Triassic boundary, everything changes. New types of tracks, not of slithering, giant, one ton Permian salamanders, but, of upright walkers. The tracks point to the prior existence of an upright standing, long legged animal about the size of a house cat. The new animal is given the scientific name of Prorotodactylus.

It appears that the Permian Extinction opened the way for a radical redirection of the evolutionary process to allow for Prorotodactylus, precursor to the dinosaurs.

In this book, Brusatte tells the complete history of the dinosaurs, drawn from the latest discoveries and cutting edge research. He brings to life the dinosaurs' origins as small shadow dwellers, descendants of Prorodactylus, through the Triassic.

The end Triassic Extinction 201 million years ago spurred another evolutionary leap forward for the dinosaurs, by killing off many of the competing mammal, amphibian, and reptile species that had kept them as smallish dinosaurs, still a marginal species during the Triassic.

The Triassic Extinction coincided with the start of the break-up of the Pangaea super continent. Around 201 million years ago the splitting continent exposed deep rifts in the earth's crust that spurred four extreme pulses of volcanic activity over a period of six hundred thousand years.

The climate changes, sea level changes, and atmospheric changes during this volatile period of volcanic activity rendered 70% of the species then on the earth extinct. Those dinosaur species that survived the Triassic Extinction were given yet another a leg up in the evolutionary process by having less competitors for the earth's resources than they had in the Triassic.

Brusatte shows how the evolution of the dinosaurs by the mid Jurassic period resulted in a spectacular flourishing and astonishing diversity of animals.

Not all dinosaurs that we know of existed at the same time. The greatest of the plant eating sauropods, like Brontosaurus, existed through the mid Jurassic period and then died out. It wasn't until ten million years before the end Cretaceous period that carnivorous, top of the food chain, T-Rex comes on the scene. Does that destroy your childhood fantasy? Knowing that T Rex never encountered a brontosaurus?

We learn about the end Cretaceous Extinction, when a giant asteroid or comet struck the planet resulting in the most extraordinary extinction event in earth's history. The comet cataclysm ended the reign of the dinosaurs on earth... except for the birds, which Brusatte explains, are just another strain of dinosaur on the dinosaur family tree. In fact, Brusatte writes explicitly: "Birds are dinosaurs."

The dinosaur process.... from the dinosaur precursor, Prorotodactylus to the Cretacious extinction, took 200 million years.
Brusatte takes the reader through how we know all of this. He recalls compelling stories of fossil discovery from his globe-trotting expeditions during one of the most exciting eras in dinosaur research - which he calls "a new golden age of discovery." He offers exciting accounts of some of the remarkable findings he and his colleagues have made, including primitive human-sized tyrannosaurs, monstrous carnivores even larger than T Rex, and paradigm-shifting feathered raptors from China.

Finally, we learn much about the exponentially expanding use of technology...big data and computer modeling... to fill in gaps in the fossil record.

Read it! My ongoing attempt to understand pre-history has been mind expanding. Trying to grasp the nature of geologic time has been mind exploding! Curiosity may have killed the cat. In my case, I hope its keeping sentient for just a little longer!

"The ULTIMATE DINOSAUR BIOGRAPHY," hails Scientific American: "A thrilling new history of the age of dinosaurs, from one of our finest young scientists. Now a New York Times bestseller!"