Permian Extinction - Comments and Book Reviews.

By Scott Arney

Theories on mass extinctions have always had a way of catching extra attention, especially of the media.  Now that the end Cretaceous mass extinction has been labeled by a general consensus that it was caused by an asteroid impact,  focus has shifted to other events such as the great Permian extinction event.

But not so fast, in my opinion.  Nature has a way of providing surprises and contradicting evidence.  Although the Associated Press and many dinosaur books state that the asteroid impact acted as the extinction cause matter-of-factly, other evidence cannot be ignored or downplayed.  There seems to be little doubt that a large impact occurred at the end of the Cretaceous, and it very well have been a contributing factor to the extinction event but extinction events are very complex and blaming worldwide dinosaur extinction on one asteroid strike seems too “convenient” and “tidy” to fit an event so profound.  The selectivity of the catastrophe and the other major events happening at the time add to the pestering details that the theory will have to address repeatedly as more is learned and discoveries take place.  Theories are made to be proven wrong, but then, proven right or wrong, theories are a cornerstone of scientific learning.  Time will tell, but the Cretaceous extinction may again gain the headlines as bold new theories challenge us to rethink what we thought was settled.

But for now the Permian extinction is commanding center stage.  This is apparent in the number of reviews, news stories and new books dedicated to the subject.  In the last year, I have noticed articles in the paper claiming that extraterrestrial radiation was the main reason for the extinction.  Another article claimed that methane being released into the atmosphere triggered the mass extinction.  Some theories hope to pin the cause on an extraterrestrial object impacting Earth (Why not?  It’s a popular theory for the end Cretaceous event.).  All of the old extinction theories are being recycled in hopes that one will fit.  Most new shining extinction theories are really old dusty ones with a new coat of paint and a new study to lend it credence.

This point brings me to the first of two books that I read this year dealing with the Permian extinction.  When Life Nearly Died-The Greatest Mass Extinction of All Time, by Michael J. Benton, covered not only the author’s views on the extinction event and his personal study but also covered the history of the “catastrophism versus gradualism” point of views as they pertain to not only extinctions but also to the whole of geological processes.  While discussing this history, Benton describes many important figures and controversies.  In addition, he discusses the difficulty in defining the Permian period and its boundaries.  Benton also describes the K/T (Cretaceous/Tertiary) extinction and focuses  in some detail on the impact event.  This appears to have been done not only to provide information on impacts and their implications for the Permian extinction event but also to further his theme of gradualism or catastrophism conflict.  He also discusses significant events during and possible causes for the Permian extinction and offers his opinions on the event.  I enjoyed his narrative of working in Russia and how it showed that access, both physically and politically, can impact geologic understanding.  Finally, he ended the book with a discussion about a possible current major mass extinction induced by man.

The second book, Gorgon-Paleontology, Obsession, and the Greatest Catastrophe in Earth’’s History, by Peter D. Ward, also focused on the Permian extinction but this time the research took place primarily in the South African Karoo Basin.  The Karoo Desert is an inhospitable place to work due to its climate and the civil unrest revalent through much of South Africa’s recent history.  Ward describes the Karoo in the preface in a way that leaves no doubt that the story will be interesting.  He takes us with him through seasons of working in the Karoo while collecting fossil specimens, mapping and drilling for core samples, the latter of which were used for paleomagnetism studies.  Along the way, we meet and become well acquainted with fellow researchers to an extent that you feel that, should you meet them, you would feel disappointed that they wouldn’t recognize you.  Ward tells his story in the first person and relays his thoughts about his work and about others in his collecting party in an honest and genuine manner. Through it all, he conveys his frustration and regrets (not to mention his deep hatred of ticks) that comes with the sacrificing required of field collecting in a place like the Karoo.  But, he also shows an almost yearning to return each season  to the same collecting party and the same harsh landscape that he had grown to know and appreciate. Ward describes also the “buckeyballs” that were touted by Luann Becker as evidence for an extraterrestrial impact at the Permian/Triassic boundary.  This was the focus of my article in the March 2001 edition of The Exposure (see Permian Extinction in the Headlines). 

Ward followed up on Becker’s research and noted that of the three boundary localities tested, one set of rocks were found to be a few million years younger than the actual boundary (Japan site), another set of rocks from the second locality (China site) did not yield similar results when tested by separate laboratories and the rocks from the third locality (Hungary site) never yielded elevated fullerene levels to begin with.  This leaves considerable doubt on this impact evidence.  Interestingly, Becker and Ward had collaborated on her work pre-publication.  After reviewing his critical comments on a copy of her preprint paper, she refused to discuss the subject with him and has since refused to work on any project with him involved and present.

Ward shares the story of an abandoned farmhouse, the family buried in the fenced family cemetery.  The dates of death were all very close, with no clue as to the fate of the family.  Only a matter of decades had passed and yet the mystery of their death remain to him a secret of the Karoo.  In a twist of irony, this family’s graveyard lies in the sediments of one of Earth’s greatest graveyards, the sediments from the Permian/Triassic boundary, sediments hundreds of millions of years old.  Ward finishes with a review of what we now know about the Permian extinction.  He leads us through the contradicting evidence and leaves us with his opinion of what caused the extinction based upon his personal observations in the Karoo.

In summary, I would recommend both books.  When Life Nearly Died was written with a lot of historical perspective which wasn’t always very exciting to me but, fortunately, Benton did include a great deal of other information such as his own field work.  His book is excellent for learning many different aspects about the Permian extinction.

Gorgon is an excellent book if you want a break from the typical textbook and go on an adventure.  This is one book that I truly didn’t want to end.  Funny side note though, gorgons were more of an icon for the book rather than a subject of the book.  They were rarely collected and not really a focus of their study.  Now I  must buy some of Peter Ward’s other books.  His stories and writing were engrossing and, truth be known, I hope his other books will take me with him back to the Karoo.  I miss it.