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I recently bought Lamarck’s Revenge by paleobiologist Peter Ward (2018) because I went on a trip and needed something to read on the flight. I just finished the book the other day and I thought that I would give a review and also discuss Coyne’s review of the book since I know he is so uptight about epigenetic theories, like that of Denis Noble and Jablonka and Lamb. In Lamarck’s Revenge, Ward (2018) purports to show that Lamarck was right all along and that the advent of the burgeoning field is “Lamarck’s revenge” for those who—in the current day—make fun of his theories in intro biology classes. (When I took Bio 101, the professor made it a point to bring up Lamarck and giraffe necks as a “Look at this wrong theory”, nevermind the fact that Darwin was wrong too.) I will go chapter-by-chapter, give a brief synopsis of each, and then discuss Coyne’s review.

In the introduction, Ward discusses some of the problems with Darwinian thought and current biological understanding. The current neo-Darwinian Modern Synthesis states that what occurs in the lifetime of the organism cannot be passed down to further generations—that any ‘marks’ on the genome are then erased. However, recent research has shown that this is not the case. Numerous studies on plants and “simpler” organisms refute the notion, though for more “complex” organisms it has yet to be proved. However, that this discussion is even occurring is proof that we are heading in the right direction in regard to a new synthesis. In fact, Jablonka and Lamb (2005) showed in their book Evolution in Four Dimensions, that epigenetic mechanisms can and do produce rapid speciation—too quick for “normal” Darwinian evolution.

Ward (2018: 3-4) writes:

There are good times and bad times on earth, and it is proposed here that dichotomy has fueled a coupling of times when evolution has been mainly through Darwinian evolution and others when Lamarckian evolution has been dominant. Darwinian in good times, Lamarckian in bad, when bad can be defined as those times when our environments turn topsy-turvy, and do so quickly. When an asteroid hits the planet. When giant volcanic episodes create stagnant oceans. When a parent becomes a sexual predator. When our industrial output warms the world. When there are six billion humans and counting.

These examples are good—save the one about when a parent becomes a sexual predator (but if we accept the thesis that what we do  and what happens to us can leave marks on our DNA that don’t change it but are passed on then it is OK)—and they all point to one thing: when the environment becomes ultra-chaotic. When such changes occur in the environment, that organism needs a physiology that is able to change on-demand to survive (see Richardson, 2017).

Ward (2018: 8) then describes Lamarck’s three-step process:

First, an animal experienced a radical change of the environment aroujnd it. Second, the initial response to the environmental change was some new kind of behavior by that of the animal (or whole species). Third, the behavioral change was followed by morphological change in subsequent generations.

Ward then discusses others before Darwin—Darwin’s grandfather Erasmus, for instance—who had theories of evolution before Darwin. In any case, we went from a world in which a God created all to a world where everything we see was created by natural processes.

Then in Chapter 2, Ward discusses Lamarck and Darwin and each of their theories in turn. (Note that Darwin did have Lamarckian views too.) Ward discusses the intellectual dual between Lamarck and Georges Cuvier, the father of the field of comparative anatomy—he studied mass extinctions. At Lamarck’s funeral, Cuvier spoke bad about Lamarck and buried his theories. (See Cuvier’s (1836) Elegy of Lamarck.) These types of arguments between academics have been going on for hundreds of years—and they will not stop any time soon.

In Chapter 3 Ward discusses Darwin’s ideas all the way to the Modern Synthesis, discussing how Darwin formulated his theory of natural selection, the purported “mechanism of evolution.” Ward discusses how Darwin at first rejected Lamarck’s ideas but then integrated them into future editions of On the Origin. We can think of this scenario: Imagine any environment and organisms in it. The environment rapidly shifts to where it is unrecognizable. The organisms in that environment then need to either change their behavior (and reproduce) or die. Now, if there were no way for organisms to change, say, their physiology (since physiology is dependent on what is occurring in the outside environment), then the species would die and there would be no evolution. However, the advent of evolved physiologies changed that. Morphologic and physiologic plasticity can and does help organisms survive in new environments—environments that are “new” to the parental organism—and this is a form of Lamarckism (“heritable epigenetics” as Ward calls it).

Chapter 4 discusses epigenetics and a newer synthesis. In the beginning of the chapter, Ward discusses a study he was a part of (Vandepas, et al, 2016). (Read Ward’s Nautilus article here.)

They studied two (so-called) different species of nautilus—one, nautilus pampilus, widespread across the Pacific and Indian Oceans and two, Nautilus stenomphalus which is only found at the Great Barrier Reef. Pompilus has a hole in the middle of its shell, whereas stenomphalus has a plug in the middle. Both of these (so-called) species have different kinds of anatomy—Pompilus has a hood covered with bumps of flesh whereas stenomphalus‘ hood is filled with projections of moss-like twig structures. So over a thirty-day period, they captured thirty nautiluses and snipped a piece of their tentacles and sequences the DNA found in it. They found that the DNA of these two morphologically different animals was the same. Thus, although the two are said to be different species based on their morphology, genetically they are the same species which leads Ward (2018: 52) to claim “that perhaps there are fewer, not more, species on Earth than science has defined.” Ward (2018: 53) cites a recent example—the fact that the Columbian and North American wooly mammoths “were genetically the same but the two had phenotypes determined by environment” (see Enk et al, 2011).

Now take Ward’s (2018: 58) definition of “heritable epigenetics”:

In heritable epigenetics, we pass on the same genome, but one marked (mark is the formal term for the place that a methyl molecule attaches to one nucleotide, a rung in the ladder of DNA) in such a way that the new organism soon has its own DNA swarmed by these new (and usually unwelcome) additions riding on the chromosomes. The genotype is not changed, but the genes carrying the new, sucker-like methyl molecules change the workings of the organism to something new, such as the production (or lack thereof) of chemicals necessary for our good health, or for how some part of the body is produced.

Chapter 5 discusses different environments in the context of evolutionary history. Environmental catastrophes that lead to the decimation of most life on the planet are the subject—something that Gould wrote about in his career (his concept of contingency in the evolutionary process). Now, going back to Lamarck’s dictum (first an environmental change, second a change in behavior, and third a change in phenotype), we can see that these kinds of processes were indeed imperative in the evolution of life on earth. Take the asteroid impact (K-Pg extinction; Cretaceous-Paleogene) that killed off the dinosaurs and threw tons of soot into the air, blocking out the sun making it effectively night (Schulte et al, 2010). All organisms that survived needed to eat. If the organism only ate in the day time, it would then need to eat at night or die. That right there is a radical environmental change (step 1) and then a change in behavior (step 2) which would eventually lead to step 3.

In Chapter 6, Ward discusses epigenetics and the origins of life. The main subject of the chapter is lateral gene transfer—the transmission of different DNA between genomes. Hundreds or thousands of new genes can be inserted into an organism and effectively change the morphology, it is a Lamarckian mechanism. Ward posits that there were many kinds of “genetic codes” and “metabolisms” throughout earth’s history, even organisms that were “alive” but were not capable of reproducing and so they were “one-offs.” Ward even describes Margulis’ (1967) theory of endosymbiosis as “a Lamarckian event“, which even Margulis accepts. Thus, the evolution of organisms is possible through lateral gene transfer and is another Lamarckian mechanism.

Chapter 7 discusses epigenetics and the Cambrian explosion. Ward cites a Creationist who claims that there has not been enough time since the 500 million year explosion to explain the diversity of body plans since then. Stephen Jay Gould wrote a whole book on this—Wonderful Life. It is true that Darwinian theory cannot explain the diversity of body plans, nor even the diversity of species and their traits (Fodor and Piatelli-Palmarini, 2010), but this does not mean that Creationism is true. If we are discussing the diversification of organismal life after mass extinctions, then Darwinian evolution cannot have possibly played a role in the survival of species—organisms with adaptive physiologies would have had a better chance of surviving in these new, chaotic environments.

It is posited here that four different epigenetic mechanisms presumably contributed to the great increase in both the kinds of species and the kinds of morphologies that distinguished them that together produced the Cambrian explosion as we currently know it: the first, now familiar, methylation; second, small RNA silencing; third, changes in the histones, the scaffolding that dictates the overall shape of a DNA molecule; and, finally, lateral gene transfer, which has recently been shown to work in animals, not just microbes. (Ward, 2018: 113)

Ginsburg and Jablonka (2010) state that “[associative] learning-based diversification was
accompanied by neurohormonal stress, which led to an ongoing destabilization and re-patterning of the epigenome, which, in turn, enabled further morphological, physiological, and behavioral diversification.” So associative learning, according to Ginsburg and Jablonka, was the driver of the Cambrian explosion. Ward (2018: 115) writes:

[The paper by Ginsburg and Jablonka] says that changes of behavior by both animal predators and animal prey began as an “arms race” in not just morphology but behavior. Learning how to hunt or flee; detecting food and mats and habitats at a distance from chemical senses of smell or vision, or from deciphering vibrations coming through water. Yet none of that would matter if the new behaviors and abilities were not passed on. As more animal body plans and the species they were composed of appeared, ecological communities changed radically and quickly. The epigenetic systems in snimals were, according to the authors, “destabilized,” andin reordering them it allowed new kinds of morphology, physiology, and again behavior, ans amid this was the ever-greater use of powerful hormone systems. Seeinf an approaching predator was not enough. The recognition of imminent danger would only save an animal’s life if its whole body was alerted and put on a “war footing” by the flooding of the creature with stress hormones. Poweful enactors of action. Over time, these systems were made heritable and, according to the authors, the novel evolution of fight or flight chemicals would have greatly enhanced survivability and success of early animals “enabled animals to exploit new niches, promoted new types of relations and arms races, and led to adaptive repsonses that became fixed through genetics.”

That, and vision. Brains, behavior, sense organs and hormones are tied to the nervous system to the digestive system. No single adaption led to animal success. It was the integration of these disparate systems into a whole that fostered survivability, and fostered the rapid evolution of new kinds of animals during the evolutionary fecund Cambrian explosion.

So, ever-changing environments are how physiological systems evolved (see Richardson, 2017: Chapters 4 and 5). Therefore, if the environment were static, then physiologies would not have evolved. Ever-changing environments were imperative to the evolution of life on earth. For if this were not the case, organisms with complex physiologies (note that a physiological system is literally a whole complex of cells) would never have evolved and we would not be here.

In chapter 8 Ward discusses epigenetic processes before and after mass extinctions. He states that, to mass extinction researchers, there are 3 ways in which mass extinction have occurred: (1) asteroid or comet impact; (2) greenhouse mass extinction events; and (3) glaciation extinction events. So these mass extinctions caused the emergence of body plans and new species—brought on by epigenetic mechanisms.

Chapter 9 discusses good and bad times in human history—and the epigenetic changes that may have occurred. Ward (2018: 149) discusses the Toba eruption and that “some small group of survivors underwent a behavioral change that became heritable, producing cultural change that is difficult to overstate.” Environmental change leads to behavioral change which eventually leads to change in morphology, as Lamarck said, and mass extinction events are the perfect way to show what Lamarck was saying.

In chapter 10 Ward discusses epigenetics and violence, the star of the chapter being MAOA. Take this example from Ward (2018: 167-168):

Causing violent death or escaping violent death or simply being subjected to intense violence causes significant flooding of the body with a whole pharmacological medicine chest of proteins, and in so doing changes the chemical state of virtually every cell. The produces epigenetic change(s) that can, depending on the individual, create a newly heritable state that is passed on to the offspring. The epigenetic change caused by the fight-or-flight response may cause progeny to be more susceptible to causing violence.

Ward then discsses MAOA (pg 168-170), though read my thoughts on the matter. (He discusses the role of epigenetics in the “turning on” of the gene. Child abuse has been shown to cause epigenetic changes in the brain (Zannas et al, 2015). (It’s notable that Ward—rightly—in this chapter dispenses with the nature vs. nurture argument.)

In Chapter 11, Ward discusses food and famine changing our DNA. He cites the most popular example, that of the studies done on survivors who bore children during or after the famine. (I have discussed this at length.) In September of 1944, the Dutch ordered a nation-wide railroad strike. The Germans then restricted food and medical access to the country causing the deaths of some 20,000 people and harming millions more. So those who were in the womb during the famine had higher rates of disorders such as obesity, anorexia, obesity, and cardiovascular incidences.

However, one study showed that if one’s father had little access to food during the slow growth period, then cardiovascular disease mortality was low. But diabetes mortality was high when the paternal grandfather was exposed to excess food. Further, when SES factors were controlled for, the difference in lifespan was 32 years, which was dependent on whether or not the grandfather was exposed to an overabundance of food or lack of abundance of food just before puberty.

Nutrition can alter the epigenome (Zhang and Kutateladze, 2018), since it can alter the epigenome and the epigenome is heritable, then these changes can be passed on to future generations too.

Ward then discusses the microbiome and epigenetics (read my article for a primer on the microbiome, what it does, and racial differences in it). The microbiome has been called “the second genome” (Grice and Segre, 2012), and so, any changes to the “second genome” can also be passed down to subsequent generations.

In Chapter 12, Ward discusses epigenetics and pandemics. Seeing people die from horrible diseases of course has horrible effects on people. Yes, there were evolutionary implications from these pandemics in that the gene pool was decreased—but what of the effects on the survivors? Methylation impacts behavior and behavior impacts methylation (Lerner and Overton, 2017), and so, differing behaviors after such atrocities can be tagged on the epigenome.

Ward then takes the discussion on pandemics and death and shifts to religion. Imagine seeing your children die, would you not want to believe that there was a better place for them after death to—somewhat—quell your sorrow over their loss? Of course, having an epiphany about something (anything, not just religon) can change how you view life. Ward also discusses a study where atheists had different brain regions activated even while no stimulation was presented. (I don’t like brain imaging studies, see William Uttal’s books and papers.) Ward also discusses the VMAT2 gene, which “controls” mood through the production of the VMAT protein, elevating hormones such as dopamine and serotonin (similar to taking numerous illegal drugs).

Then in Chapter 13 he discusses chemicals and toxins and how they relate to epigenetic processes. These kinds of chemicals and toxins are linked with changes in DNA methylation, miroRNAs, and histone modifications (Hou et al, 2012). (Also see Tiffon, 2018 for more on chemicals and how they affect the epigenome.)

Finally, in Chapter 14 Ward discusses the future of evolution in a world with CRISPR-CAS9. He discusses many ways in which the technology can be useful to us. He discusses one study in which Chinese scientists knocked out the myostatin gene in 65 dog embryos. Twenty-seven of the dogs were born and only two—a male and a female—had both copies of the myostatin gene disrupted. This is just like when researchers made “double-muscle” cattle. See my article ‘Double-Muscled’ Humans?

He then discusses the possibility of “supersoldiers” and if we can engineer humans to be emotionless killing machines. Imagine being able to engineer humans that had no sympathy, no empathy, that looked just like you and I. CRISPR is a tool that uses epigenetic processes and, thus, we can say that CRISPR is a man-made Lamarckian mechanism of genetic change (mimicking lateral gene transfer).

Now, let’s quickly discuss Coyne’s review before I give my thoughts on the book. He criticizes Ward’s article linked above (Coyne admits he did not read the book), stating that his claim that the two nautiluses discussed above being the same species with the same genome and epigenetic forces leading to differences in morphology (phenotype). Take Coyne’s critique of Vandepas, et al, 2016—that they only sequenced two mitochondrial genes. Combosch et al (2017; of which Ward was a coauthor) write (my emphasis):

Moreover, previous molecular phylogenetic studies indicate major problems with the conchiological species boundaries and concluded that Nautilus represents three geographically distinct clades with poorly circumscribed species (Bonacum et al, 2011; Ward et al, 2016). This is been reiterated in a more recent study (Vandepas et al, 2016), which concluded that N. pompilius is a morphologically variable species and most other species may not be valid. However, these studies were predominantly or exclusively based on mitochondrial DNA (mtDNA), an informative but often misleading marker for phylogenetic inference (e.g., Stöger & Schrödl 2013) which cannot reliably confirm and/or resolve the genetic composition of putative hybrid specimens (Wray et al, 1995).

Looks like Coyne did not look hard enough for more studies on the matter. In any case, it’s not just Ward that makes this argument—many other researchers do (see e.g., Tajika et al, 2018). So, if there is no genetic difference between these two (so-called) species, and they have morphological differences, then the possibility that seems likely is that the differences in morphology are environmentally-driven.

Lastly, Coyne was critical of Ward’s thoughts on the heritability of histone modification, DNA methylation, etc. It seems that Coyne has not read the work of philosopher Jan Baedke (see his Google Scholar page), specifically his book Above the Gene, Beyond Biology: Toward a Philosophy of Epigenetics along with the work of sociologist Maurizio Meloni (see his Google Scholar page), specifically his book Impressionable Biologies: From the Archaeology of Plasticity to the Sociology of Epigenetics. If he did, Coyne would then see that his rebuttal to Ward makes no sense as Baedke discusses epigenetics from an evolutionary perspective and Meloni discusses epigenetics through a social, human perspective and what can—and does—occur in regard to epigenetic processes in humans.

Coyne did discuss Noble’s views on epigenetics and evolution—and Noble responded in one of his talks. However, it seems like Coyne is not aware of the work of Baedke and Meloni—I wonder what he’d say about their work? Anything that attacks the neo-Darwinian Modern Synthesis gets under Coyne’s skin—almost as if it is a religion for him.

Did I like the book? I thought it was good. Out of 5 stars, I give it 3. He got some things wrong, For instance, I asked Shea Robinson, author of Epigenetics and Public Policy: The Tangled Web of Science and Politics about the beginning of the book and he directed me to two articles on his website: Lamarck’s Actual Lamarckism (or How Contemporary Epigenetics is not Lamarckian) and The Unfortunate Legacy of Jean-Baptiste Lamarck. The beginning of the book is rocky, the middle is good (discussing the Cambrian explosion) and the end is alright. The strength of the book is how Ward discusses the processes that epigenetics occurs by and how epigenetic processes can occur—and help drive—evolutionary change, just as Jablonka and Lamb (1995, 2005) argue, along with Baedke (2018). The book is a great read, if only for the history of epigenetics (which Robinson (2018) goes into more depth, as does Baedke (2018) and Meloni (2019)).

Lamarck’s Revenge is a welcome addition to the slew of books and articles that go against the Modern Synthesis and should be required reading for those interested in the history of biology and evolution.