Rivers in Time: The Search for Clues to Earth's Mass Extinctions

by Peter D. Ward

Several times in the distant past, catastrophic extinctions have swept the Earth, causing more than half of all species―from single-celled organisms to awe-inspiring behemoths―to suddenly vanish and be replaced by new life forms. Today the rich diversity of life on the Earth is again in grave danger―and the cause is not a sudden cataclysmic event but rather humankind's devastation of the environment. Is life on our planet teetering on the brink of another mass extinction? In this absorbing new book, acclaimed paleontologist Peter D. Ward answers this daunting question with a resounding yes.

Elaborating on and updating Ward's previous work, The End of Evolution , Rivers in Time delves into his newest discoveries. The book presents the gripping tale of the author's investigations into the history of life and death on Earth through a series of expeditions that have brought him ever closer to the truth about mass extinctions, past and future. First describing the three previous mass extinctions―those marking the transition from the Permian to the Triassic periods 245 million years ago, the Triassic to the Jurassic 200 million years ago, and the Cretaceous to the Tertiary 65 million years ago―Ward assesses the present devastation in which countless species are coming to the end of their evolution at the hand of that wandering, potentially destructive force called Homo sapiens.

The book takes readers to the Philippine Sea, now eerily empty of life, where only a few decades of catching fish by using dynamite have resulted in eviscerated coral reefs―and a dramatic reduction in the marine life the region can support. Ward travels to Canada's Queen Charlotte Islands to investigate the extinctions that mark the boundary between the Triassic and Jurassic periods. He ventures also into the Karoo desert of southern Africa, where some of Earth's earliest land life emerged from the water and stood poised to develop into mammal form, only to be obliterated during the Permian/Triassic extinction.

Rivers of Time provides reason to marvel and mourn, to fear and hope, as it bears stark witness to the urgency of the Earth's present Ward offers powerful proof that if radical measures are not taken to protect the biodiversity of this planet, much of life as we know it may not survive.

Genres: Science, Nonfiction, Biology, History, Geology, Popular Science, Evolution

320 pages, Hardcover

First published March 15, 2000

About the author

Peter Douglas Ward is an American paleontologist and professor of Biology and of Earth and Space Sciences at the University of Washington, Seattle. He has written popular numerous science works for a general audience and is also an adviser to the Microbes Mind Forum.

His parents, Joseph and Ruth Ward, moved to Seattle following World War II. Ward grew up in the Seward Park neighborhood of Seattle, attending Franklin High School, and he spent time during summers at a family summer cabin on Orcas Island.

Ward's academic career has included teaching posts and professional connections with Ohio State University, the NASA Astrobiology Institute, the University of California, McMaster University (where he received his PhD in 1976), and the California Institute of Technology. He was elected as a Fellow of the California Academy of Sciences in 1984.

Ward specializes in the Cretaceous–Paleogene extinction event, the Permian–Triassic extinction event, and mass extinctions generally. He has published books on biodiversity and the fossil record. His 1992 book On Methuselah's Trail received a Golden Trilobite Award from the Paleontological Society as the best popular science book of the year. Ward also serves as an adjunct professor of zoology and astronomy.

His book The End of Evolution was published in 1994. In it, he discussed in three parts, each about an extinction event on earth.

Ward is co-author, along with astronomer Donald Brownlee, of the best-selling Rare Earth: Why Complex Life Is Uncommon in the Universe, published in 2000. In that work, the authors suggest that the universe is fundamentally hostile to advanced life, and that, while simple life might be abundant, the likelihood of widespread lifeforms as advanced as those on Earth is marginal. In 2001, his book Future Evolution was published, featuring illustrations by artist Alexis Rockman.

Ward and Brownlee are also co-authors of the book The Life and Death of Planet Earth: How the New Science of Astrobiology Charts the Ultimate Fate of the World, which discusses the Earth's future and eventual demise as it is ultimately destroyed by a warming and expanding Sun.

According to Ward's 2007 book, Under a Green Sky, all but one of the major mass extinction events in history have been brought on by climate change—the same global warming that occurs today. The author argues that events in the past can give valuable information about the future of our planet. Reviewer Doug Brown goes further, stating "this is how the world ends." Scientists at the Universities of York and Leeds also warn that the fossil record supports evidence of impending mass extinction.

Reviews

[Neil · Rating 3 out of 5]

Three stars, being generous. Part of me wants to give it two stars, but I misunderstood what the book was going to be about. For some reason, I thought it was going to be about the the impact the disappearance of ancient rivers had on the surrounding environment/ecosystem, and that was not what this book was about. I suspect I read the dust jacket of a different book at the library that was sitting next to this book, and when I came back to grab that book I grabbed this one by mistake. In any case, what I read was not what I expected.

It was an odd book for me - it was extremely boring and long for me, but at the same time it held my interest enough to keep reading it to the end. I did find humor in the book - mostly when the author made hypothetical states in an emphatic manner as if his statements were true and not just his opinion or educated guesswork. Also, on page 280 - he makes the statement, "Today meteorologists find it almost impossible to predict the weather more than a few days in advance because many atmospheric phenomena exhibit chaotic rather than predictable behavior" and goes on to describe how the new science of chaos theory was originally derived from studies of the atmosphere. I found this statement hilarious because I interpreted it as the author saying that meteorologists at one time were able to accurately predict the weather. I would beg to differ on this as weathermen have never seemed to be able to accurately predict weather over three days in advance for the longest time (they have become better through using computers to model the weather and make more accurate forecasts). Granted, this book was written in 2000, so that might have something to do with it.

I wish I had noted the page number; he also made comment about 2015 and maybe 2020, and I find myself wishing I had looked up what he said to see how accurate he was.

I think the best part of the book for me was when he was describing his experiences in the former Soviet Block country of Georgia. That chapter really caught my attention, but it was also quite a bit more personal and personable than most of the book.

He would do this thing where he would start talking about the fossils that could be found in a particular region in another country (or part of the country) and then go back to how much better it was to find the information one was looking for in Karoo, South Africa, or Hell Creek, Montana (or how you got better results in either of these two places). That kind of annoyed me because it broke up what he was saying about the region he had been talking about; it broke up my train of thought because of how it backtracked. But maybe some of the book was written "stream of thought", so those "sections" that stuck out to me might have been important enough for him to include when he did lest he forget what he wanted to say if he came back to it later.

I did enjoy his discussions of what some of the dinosaurs and other prehistoric creatures might have been like before the different extinctions occurred. It was also interesting to learn how some creatures were already going extinct before the K-T extinction event occurred, and how some extinctions occurred after the K-T line - I did not know that; I had always heard that when the K-T "event" occurred, that was it. But it was actually a mix of volcanic eruptions, the changing atmosphere, and the meteor strike(s) that cause the mass extinctions that occurred round the K-T line.

I think the other part of the book I enjoyed the most was the discussion of the megafauna that lived up until around 10,000 - 12,000 years ago. I knew of some of the giant creatures that lived in North America, but had no idea of the wide range and diversity of creatures that lived in both North and South America. I also recognized some of what the author talked about because of a class about North America's "ancient history" I took last semester, so that was pretty cool, too.

In any case, it was surprising to learn about the extinctions that occurred on the various islands of the Pacific. The author focuses on the Hawaiian Islands but also talks about other islands as well. I had no idea that these extinctions occurred on these islands when humans first landed - one always gets the impression the islanders always lived "in peace and harmony" with the environment and it wasn't until the arrival of the Europeans that everything went south, so it was interesting to learn otherwise (same as with the Americas).

Not sure how much of a "spoiler" this is, but it's kinduva gripe. While it was interesting to learn that Hawaii did not have mosquitos for the longest time, I found myself wondering how true his anecdote was that it was an American ship from Mexico stopping at Hawaii in the 1820s that introduced mosquitos to the island chain. The author's claim is that they dumped their mosquito larva-tainted stale water from Mexico into a pond and scooped out fresh water for their barrels for the rest of their trip, and that is how mosquitos were introduced. Why couldn't it have been a European ship? I did run an online search about this, and the online search stated it was either an American ship or a European ship, which mollified me, hahahah.

Also, I had no idea Hawaii was 2,500 miles from North America! I never thought to look it up, so that was a bit of a shock, hahahah.

There were a couple of lines that did catch my attention. One was on page 88 - The earliest rocks of the Mesozoic age are called the Triassic System. They are easily recognized virtually anywhere on Earth because of their distinctive color: bright red. It is as if the earth, having killed off most of the animals in the P/T event, became stained by the blood of the dead. That was a powerful, colorful, evocative line and really grabbed my attention. It also kinda reminded me of the old line about nature/evolution: red in tooth and claw. But, yeah, it was a powerful use of imagery to describe the extinction that occurred at the P/T event.

The other was how the author ended the book - There will never be a new dominant fauna on the earth other than humanity and its domesticated vassals until we go extinct - and if we succeed in reaching the stars, that may never happen. We are at the pinnacle of biodiversity on this planet. We have dominion. (bold added) I thought it was a powerful ending. It was like the author was saying, "We can go one of two ways, here - but the choice is ours", but he is pretty much pessimistic throughout the entire book that I feel like he has little hope for mankind and its stewardship of our planet. However, I did appreciate this honest, as he relates an anecdotal story how if he had to choose between feeding his family and ensuring an endangered species would go on living, he would kill the endangered species to make sure his family was fed. I think he was emphasizing with how those who are poor will do what they have to do to provide food and support for their families, and the fact that an endangered species might to extinct as a result is irrelevant to them when it comes to providing for their families.

He makes a comment about the people of the Soviet Union (Russia) and how angry he was. I think "the issue" here is that he fails to make a distinction between the Soviet military and the Russian citizens. He claims he feels he was lied to about the strength and dominance of the Soviet military and how dangerous they were when he saw the levels of poverty of the common people in former Communist countries. I always had a distinction in my mind between the Soviet military forces and the common people of the communist countries - I respected (and maybe feared a little bit) what the Soviet military could do, but I never applied those feelings to the common citizens that I can remember. The strength and dominance, the threat, of the Soviet military has absolutely nothing to do with the poverty levels forced upon the civilians in order to keep the military "strong." He's not making a proper association, here, when he vents about this.

I could not believe the number of animals that were killed "just because." He describes a hunt that occurred . . . somewhere in the United States - Pennsylvania, maybe? in which hunters positioned a half-mile apart on the 100-mile-circumference of a circle and moved inwards, killing everything they came across. That was heart-breaking, as were some other similar events he described. Hunting to extinction in order to survive is one thing; killing indiscriminately for no reason (that he gave) is something else. Granted, he never gave the reason why this hunt (or other such hunts occurred), so there might have been a "logical" reason for what happened (or seemed "right" at the time), but the author never provides the reader with this reason.

So, I have said a bit more than I thought I would say. The "mystery" of the two "ancient" extinction events (P/T & K-T) remained a bit of a mystery in my opinion. He presents different theories and ideas, but I never felt like they coalesced into something "definitive" (which is fine; it's not like we will ever know). The third "mass extinction" is the Modern Mass Extinction that is going on right now. Twenty-four years ago, the author was very pessimistic that things would change for the better. Unfortunately, that pessimism is well-found and things have not improved for the better. Who knows? Maybe humanity will wake up sooner rather than later and make the appropriate changes that will allow today's pace to slow down enough that many of the non-Human species sharing the planet with us will "make a comeback" and no longer be endangered let alone go extinct.

In the end, I will leave it at three stars. While it is not the book I intended to read, I am glad that I read it.

[Yael · Rating 5 out of 5]

Mass extinctions hold many mysteries, particularly the largest ones Earth has ever experienced. In Rivers in Time, Peter Ward presents what is known -- and not known -- about great mass extinctions, especially the Permian-Triassic, K/T, and Modern ones. As protected as we in the West are from natural hazards, it is hard for us to entertain the idea that we, too, could someday be wiped from the face of the Earth by some enormous catastrophe; for that reason, recognition of the fact of mass extinctions among scientists was long in coming, and even now many still don't accept that whole biotas that once existed on Earth were destroyed by the hand of a malevolent nature. Nor is it yet widely accepted that we ourselves may be responsible for the extinction of whole suites of plants and animals, some in prehistoric times, many becoming extinct within the last few decades.

Dr.Ward first describes three of the greatest of Earth's mass extinctions and their likely causes: the one at the end of the Permian Period of the Paleozoic Era, 251 million years ago; the one that closed out the Triassic Period of the Mesozoic Era, 200 million years ago; and the one that closed out the Cretaceous Period, the last of the Mesozoic Era, 65 million years ago. And then he goes on to detail the extinction of the great megafauna in much of the world some 40,000 to 10,000 years ago, which may or may not have been caused, at least in part, by human activity; and the current human devastation of the world's ecosystems which, beginning in the last 2,000 years, is rapidly obliterating what is left of formerly virgin ecosystems and their inhabitants.

Dr. Ward's careful and painstaking descriptions and analyses of these mass extinctions makes it clear that the world has suffered great body-blows numerous times that left it virtually empty. Life has always recovered from these disasters, but slowly, the gaping holes left in the ecological dynamics of the world by catastrophe requiring a great deal of time and a good deal of luck to heal. Never has the world regained what it has lost after the greatest mass extinctions; the biotas that replace those destroyed by catastrophe are not like their predecessors. The Age of Mammal-Like Reptiles, the Paleozoic, was replaced by the Age of Dinosaurs, the Mesozoic, which in turn was replaced by the Age of Mammals, the Cenozoic. The plants, the flowing waters, the very atmosphere of each age was unique to it, not to be replicated in following ages. Which begs the question: What will replace the countless species of creatures made extinct by human activities, almost certainly including humanity itself? What will the life of the ages to come be like? Will they be worlds of rats, cockroaches, and weeds, however these diversify into new life-forms?

Dr. Ward is a convincer. Where there isn't enough evidence yet to determine exactly how a suite of creatures became extinct, he doesn't push any one explanation for their extinction. But where the evidence is abundant and well-analyzed, he shows, with care and precision, what almost certainly happened to a lost biota, and what came after it. Given its subject, this book could have been savagely depressing. But Dr. Ward, who is as much a poet as a scientist, writes so beautifully that his prose carries the reader through in spite of the book's dark subject. I was stunned at the sheer depth and loveliness of this work, captured by its beauty. And, as in many of his other books, Dr. Ward doesn't hesitate to include his own experiences as part of life's narrative. His descriptions of his travels around the world and his psrticipation in the most important paleontological discoveries of our times give this book a richness and texture it would not otherwise have.

This is yet another book I plan to add to my own personal library, as soon as possible, as much because of the reading pleasure it has afforded me as for its scientific value. On a scale of 1-5, I give this book a 6.

[Kitty · Rating 4 out of 5]

Gives a feel for the life of a paleontologist - fascinating stuff!

The last few chapters on the extent of the currently occurring mass extinction are devastating. Even though Dr. Ward says things like "unless we do something" about the health of our biosphere, it seems that we've started a juggernaut we can only ride, not control.

This loss of species diversity and habitat was not a thing planned by humans, or even completely our doing. But its ramp-up is a consequence of our global actions and might be helped by a global response. However, given what a fractious species we are, it seems unlikely that we will all agree enough to do much in the way of slowing the ecological degradation of our home.

As the author says at the end of this book, "There will never be a new dominant fauna on the earth other than humanity and its domesticated vassals until we go extinct--and if we succeed in reaching the stars, that may never happen.

We are at the pinnacle of biodiversity on this planet. We have dominion."

Yikes.

[Ballpeendash · Rating 5 out of 5]

This book is really good for anyone who wants a slightly more than general knowledge of the major mass extinctions of both the past and present (yes, I said present, as in current).
It starts with the Permian/Triassic event, then on to the Triassic/Jurassic, K/T, and finally what is called the Modern Mass Extinction.

[Peter]

Loved it. Very entertaining and informative.