George R. McGhee Jr.’s Carboniferous Giants and Mass Extinction: The Late Paleozoic Ice Age World is not light reading. It is an academic treatise delving into climate change and geology, and related evolution, of the Carboniferous period. The Carboniferous was about 60 million years long, followed the Devonian and preceded the Permian, and the name refers to the giant amounts of coal that apparently formed during this period. This was a warm period and a period with multiple ice ages. The time span covered in this book, which goes well more recent than just the Carboniferous, is plenty long enough for all the continents to travel great distances, and the basic configuration of the Earth to change. There were periods so warm that multi-cellular land life likely did not exist at all in the tropics. The arctic was covered with a continent and it was very warm and lush, even if dark for half the time.

This is probably the time for a book like this, since over the last decade or so a great deal of field research and laboratory analysis of isotopes and other invisible things has led us to the point where a comprehensive overview of great and deep time, globally, is possible without the use of truthy but overdone generalizations. You get the sense form McGhee’s book of significant variation across space and time that is understood at some level of detail. Paleontology turns time machine at a finer scale than usual. You also get a sense of the bigness of change that can happen in the ecological systems we have here on Earth. It is very big. Outright scary, in fact.

As noted, this is not a light and airy science book written by a skilled science writer. It is a deep dive written by an expert who has the rare capacity to put a vast array of information into perspective. The black and white illustrations are very well chose and executed and in some cases startling. I give this read a strong yes.

ABOUT THE AUTHOR
George R. McGhee Jr. is Distinguished Professor of Paleobiology at Rutgers University and a fellow of the Konrad Lorenz Institute for Evolution and Cognition Research in Klosterneuburg, Austria. He has held research positions at the University of Tubingen, the Field Museum of Natural History, and the American Museum of Natural History. His books include The Late Devonian Mass Extinction: The Frasnian/Famennian Crisis (1996); Theoretical Morphology: The Concept and Its Applications (1999); and When the Invasion of Land Failed: The Legacy of the Devonian Extinctions (2013), from Columbia University Press.

TOC:

Preface
1. Harbingers of the Late Paleozoic Ice Age
2. The Big Chill
3. The Late Carboniferous Ice World
4. Giants in the Earth . . .
5. The End of the Late Paleozoic Ice Age
6. The End of the Paleozoic World
7. The Legacy of the Late Paleozoic Ice Age
Notes
References
Index

…during an expedition … in December 2013, I spotted a small green frog … Atelopus balios… no populations had been found since 1995, and it was thought to be extinct. But here it was, raised from the dead like Lazarus. My colleagues and I found several more that night, males and females, and shipped them to an amphibian ark in Quito, where they are now breeding safely in captivity. But they will go extinct one day, and the world will be none the poorer for it. Eventually, they will be replaced by a dozen or a hundred new species that evolve later.

Mass extinctions periodically wipe out up to 95 percent of all species in one fell swoop; these come every 50 million to 100 million years, and scientists agree that we are now in the middle of the sixth such extinction…

But the impulse to conserve for conservation’s sake has taken on an unthinking, unsupported, unnecessary urgency. Extinction is the engine of evolution, the mechanism by which natural selection prunes the poorly adapted and allows the hardiest to flourish. …

Climate scientists worry about how we’ve altered our planet, and they have good reasons for apprehension: Will we be able to feed ourselves? Will our water supplies dry up? Will our homes wash away? But unlike those concerns, extinction does not carry moral significance, even when we have caused it….

Yet we are obsessed with reviving the status quo ante. The Paris Accords aim to hold the temperature to under two degrees Celsius above preindustrial levels, even though the temperature has been at least eight degrees Celsius warmer within the past 65 million years. Twenty-one thousand years ago, Boston was under an ice sheet a kilometer thick. We are near all-time lows for temperature and sea level …

This is how evolution proceeds: through extinction….

Conserving biodiversity should not be an end in itself; diversity can even be hazardous to human health. Infectious diseases are most prevalent and virulent in the most diverse tropical areas. …

And if biodiversity is the goal of extinction fearmongers, how do they regard South Florida, where about 140 new reptile species accidentally introduced by the wildlife trade are now breeding successfully? No extinctions of native species have been recorded, and, at least anecdotally, most natives are still thriving….

If climate change and extinction present problems, the problems stem from the drastic effects they will have on us. A billion climate refugees, widespread famines, collapsed global industries, and the pain and suffering of our kin demand attention to ecology and imbue conservation with a moral imperative. A global temperature increase of two degrees Celsius will supposedly raise seas by 0.2 to 0.4 meters, with no effect on vast segments of the continents and most terrestrial biodiversity. …

First, we don’t practice a general, thoughtless, conservation policy. The author is apparently unaware that our species had developed, in most nations and internationally, a system of identifying conservation problems and addressing them. It is not perfect, but when compared to other systems, such as identifying major health risks, emergent diseases, regional episodes of starvation, or outbreaks of armed conflict, it does as well as other systems, and is probably better than average.

Second, despite the aforementioned attempt to be smart, we are also ignorant. For example, there is a theory that the removal of keystone species has a disproportionately large effect other life forms. Key seed disperses, for example, might be essential for maintenance of important biodiversity in a forest. But, what if there are a dozen species that account for 80% of the dispersal, with one of those accounting for 70%? If that one keystone disperser were to go extinct, would that cause problems for all the other dispersers, since most dispersers also rely on the plant producing the seeds they are dispersing? Or, would one or two of the other dispersers simply and quickly take over the role of the newly extinct keystone species? Answer: We don’t know and neither does R. Alexander Pyron.

For the first of these two reasons, we should not assume we are ignorant and that R. Pyron can teach us something we don’t know. Conservation is clearly not his area of expertise. (I’ve read his resume; It isn’t.) For the second of these two issues, while we can and do make efforts to be specifically smart about our decisions with respect conservation, we also need to have a general principle of opting in favor of conservation-enhancing measures where possible, because we really, honestly, don’t know the ways in which we can screw up. A good principle is to leave stuff alone when we can.

Third, mass extinctions certainly are part of life. They happen now and then. Big giant ones have happened a half dozen times or so, and there have been a larger number of medium sized ones. Mass extinctions have two interesting characteristics. One, when the most severe ones happen, we see that life comes close to getting entirely wiped out. Here is where a form of the Anthropocentric Effect comes into play. We live in the world where mass extinctions of the past have almost, but not actually, ended life on the planet (or, perhaps better stated and more relevant, ended multi-cellular life on the planet). Why do we live on a planet where life almost, but not quite, ends now and then? Because it didn’t. Had it, we would not be living here to revel in how amazing it is that life always survives. In myriad hypotheical alternative universes, the Earth is at present inhabited by slime and nothing else, because the worst mass extinctions were slightly worse than the ones that actually happened here, which is why we are here to tell about it.

The truth is that one of these days we are going to have a mass extinction that does either wipe out all life, or all but perhaps bacteria and one kind of fungus, or something close to that. R. Pyron is fine with that. I am not. He is wrong.

The second characteristic of mass extinctions is that everything gets rearranged and nothing is the same thereafter. My favorite is the pair of events that occurred very close in time at the end of the Permian. Prior to those back to back events, most, or at least a very large percentage, of animals that we were sessile — attached to things — while many, if not most, photo-synthesizers were not. After the Permian, things changed, and most plants were planted and most animals were perambulating by some means. Alexander Pyron wants us to focus on saving humans, and never mind extinctions in general. He lacks understanding of what he writes.

R is wrong about all of the climate change related things he says. He is abysmally wrong, and is clearly repeating standard long disproved, themes of the climate denial, anti science community. Yes, folks, we found another to add to the dozen or so nearly extinct ones we knew about. Like those frogs. A tenured scientist who is a climate science denier!

The current and likely future with respect to sea levee rise is meters, not tenths of meters. The current sea levels are already on the high end for the Pleistocene, not low. Lower sea levels during the last glacial were much lower. The fact that it was warmer 65 million years ago is irrelevant, since our entire ecology, including all of the plants and animals we rely on, are categorically distinct from anything that lived then. R demonstrates in this part of his essay a Middle School level understanding of all things paleo, not what one would expect from a tenured professor of biology who supposedly studies evolution.

His comments about Florida demonstrate a dangerous ignorance. The introduction of what become invasive species is nearly universally bad, and this one kind of event is responsible for more extinction in this world than any other thing. When R. tells us that invasive species are not a problem because of Florida, he is conveying a pernicious and dangerous falsehood. If he understand that he has this wrong then he has carried out a nefarious act in writing this essay, and we need to wonder why. If he does not understand that he has this wrong, then he had demonstrated deep and disturbing ignorance. Maybe there is a third reason, but I don’t see it.

By the way, the pattern he claims for Florida, specifically, might be partly true, but there are reasons for this having to to with the region’s unique bio-geography as a peninsula jutting down into a tropical region, as well as its history as part of an earlier mass extinction event across the Caribbean. This is all interesting stuff that R is apparently ignorant of.

He does seem to be concerned with climate refugees, and he does admit that we might want to avoid some of the effects of climate change. But these ameliorating comments are buried in a larger Lomborgian style argument that we should not be concerned about extinctions, climate change, all of that.

There is an editor at the Washington Post that totally stepped in it.