An interview with Paul Wignall: How life on earth survived mass extinctions

Wignall jacketAs scientists ponder NASA’s recent announcement about the likelihood of water and the possibility of life, or extinct life on Mars, Paul Wignall, professor of palaeoenvironments at the University of Leeds, explores a calamitous period of environmental crisis in Earth’s own history. Wignall has been investigating mass extinctions for more than twenty-five years, a scientific quest that has taken him to dozens of countries around the world. Recently he took the time to answer some questions about his new book, The Worst of Times: How Life on Earth Survived Eighty Million Years of Extinctions.

So why was this the worst of times and what died?

PW: For 80 million years, there was a whole series of mass extinctions; it was the most intense period of catastrophes the world has ever known. These extinctions included the end-Permian mass extinction, the worst disaster of all time. All life on earth was affected, from plankton in the oceans to forests on land. Coral reefs were repeatedly decimated, and land animals, dominated by primitive reptiles and amphibians, lost huge numbers of species.

What was responsible for all of these catastrophes?

PW: There is a giant smoking gun for every one of these mass extinctions: vast fields of lava called flood basalts. The problem is how to link their eruption to extinction. The key is understanding the role of volcanic gas emissions. Some of these gases, such as carbon dioxide, are very familiar to us today, and their climatic effects, especially global warming, seem to have been severe.

Why did these catastrophes stop happening?

PW: This is the $64,000 dollar question at the core of The Worst of Times. It seems to be because of a supercontinent. For 80 million years, all continents were united into a single entity called Pangea. This world was extremely bad at coping with rapid global warming because the usual feedbacks involved in removing gases from the atmosphere were not functioning very well. Since then, Pangea has broken up into the familiar multi-continent world of today, and flood basalt eruptions have not triggered any more mass extinctions.

What were the survivors like?

PW: Very tough and often very successful. It takes a lot to survive the world’s worst disasters, and many of the common plants and animals of today can trace their origin back to this time. For example, mollusks such as clams and snails were around before this worst of times, and their survival marks the start of their dominance in today’s oceans.

Are there any lessons we can apply to modern day environmental worries?

PW: Yes and no. Rapid global warming features in all of the mass extinctions of the past, which should obviously give us cause for concern. On the plus side, we no longer live in a supercontinent world. Flood basalt eruptions of the recent geological past have triggered short-lived phases of warming, but they have not tipped the world over the brink.

Paul Wignall at Otto Fiord at Cape St Andrew.

Paul Wignall conducting field research at Otto Fiord at Cape St Andrew.

Does this have anything to do with the dinosaurs?

PW: Sort of. Dinosaurs first appear towards the end of this series of calamities and to a great extent they owed their success to the elimination of their competitors, which allowed them to flourish and dominate the land for 140 million years. As we know, their reign was brought to an abrupt halt by a giant meteorite strike – a very different catastrophe to the earlier ones.

What would you say to those who want to know how you can claim knowledge of what happened so long ago?

PW: Geologists have a lot of ways to interpret past worlds. The clues lie in rocks, so mass extinction research first requires finding rocks of the right age. Then, once samples have been collected, analysis of fossils tells us the level where the extinctions happened. This level can then be analyzed to find out what the conditions were like. It’s like taking a sample of mud from the bottom of the ocean and then using it reconstruct environmental conditions. However, not everything gets “fossilized” in ocean sediments. For example, it is very hard to work out what past temperatures were like, and ocean acidity levels are even harder to determine. This leaves plenty of scope for debate, and The Worst of Times looks at some of these on-going scientific clashes.

Read chapter 1 here.


Bender_Paleoclimate “Michael Bender, a giant in the field, fits the excitement, rigor, and deep insights of paleoclimatology into a succinct text suitable for a semester-long course introducing this indispensable branch of environmental science.”–Richard B. Alley, Pennsylvania State University

Michael L. Bender

In this book, Michael Bender, an internationally recognized authority on paleoclimate, provides a concise, comprehensive, and sophisticated introduction to the subject. After briefly describing the major periods in Earth history to provide geologic context, he discusses controls on climate and how the record of past climate is determined. The heart of the book then proceeds chronologically, introducing the history of climate changes over millions of years–its patterns and major transitions, and why average global temperature has varied so much. The book ends with a discussion of the Holocene (the past 10,000 years) and by putting manmade climate change in the context of paleoclimate.

The most up-to-date overview on the subject, Paleoclimate provides an ideal introduction to undergraduates, nonspecialist scientists, and general readers with a scientific background.


Watch Michael Bender discuss Paleoclimate at the Fundamentals of Climate Science Symposium at Princeton University

Request an examination copy.


Climate Dynamics

Cook_Climate_Dynamics “Climate change and its impacts are being embraced by a wider community than just earth scientists. A useful textbook, Climate Dynamics covers the basic science required to gain insights into what constitutes the climate system and how it behaves. While still being quantitative, the material is written in a lecture-note style that creates a simplified, but not simple, approach to teaching this complex subject.”–Chris E. Forest, Pennsylvania State University

Climate Dynamics
Kerry H. Cook

Climate Dynamics is an advanced undergraduate-level textbook that provides an essential foundation in the physical understanding of the earth’s climate system. The book assumes no background in atmospheric or ocean sciences and is appropriate for any science or engineering student who has completed two semesters of calculus and one semester of calculus-based physics.

  • Makes a physically based, quantitative understanding of climate change accessible to all science, engineering, and mathematics undergraduates
  • Explains how the climate system works and why the climate is changing
  • Reinforces, applies, and connects the basic ideas of calculus and physics
  • Emphasizes fundamental observations and understanding


Table of Contents

Sample this book:

Chapter 1 [PDF]

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New Earth Science Catalog

Be among the first to check out our new Earth Science catalog at:

Three new titles in the The Princeton Primers in Climate series are featured in the catalog.  Michael L. Bender’s Paleoclimate makes an ideal introduction to the subject. In Climate and Ecosystems, David Schimel looks at how Earth’s living systems profoundly shape the physical world. David Randall’s Atmosphere, Clouds, and Climate offers a short, reader-friendly introduction to atmospheric processes. There are more books in the series and you can find information at: . We invite you to browse and download the catalog to find more great books by great authors.

Are you going to the annual American Geophysical Union meeting in San Francisco? We’ll be there at booth 634. Charles H. Langmuir & Wally Broecker will be in our booth on Wednesday, Dec 5th at 3:30 p.m. signing copies of their revised and expanded book, How to Build a Habitable Planet. This classic account of how our habitable planet was assembled from the stuff of stars introduced readers to planetary, Earth, and climate science by way of a fascinating narrative. Now this great book has been made even better. Stop by and chat with the authors. We hope to see you there.

How would you like to receive timely e-mail announcements about new Princeton books in earth science? Follow the link for a quick and easy sign-up: . Your e-mail address will remain strictly confidential.

New Earth Science Catalog

catalog coverWe invite you to be among the first to download and browse our 2012 Earth Science catalog at:

Check out what is new in our Princeton Primers in Climate series. You will find books by Geoffrey K. Vallis, Shawn J. Marshall, David Randall and David Archer. Princeton Primers in Climate is a new series of short, authoritative books that explain the state of the art in climate-science research. Written specifically for students, researchers, and scientifically minded general readers looking for succinct and readable books on this frequently misunderstood subject, these primers reveal the physical workings of the global climate system with unmatched accessibility and detail.

We are celebrating the new series at the AGU annual meeting in San Francisco on Tuesday, December 6th.  You are invited to join us at our exhibit booth (no. 1449) at 3:30 p.m. for the party.  We hope to see you there.