To celebrate Darwin Day, we are interviewing our Darwinian authors. First up is David Reznick who is the author of The Origin Then and Now: An Interpretive Guide to the Origin of Species. Of the book, SEED Magazine wrote, “Reznick . . . succeeds where others have failed–instead of annotating the dense, Victorian prose of the Origin or recasting it as a popular narrative, he paraphrases each chapter of the book, adding fascinating elaborations on why Darwin chose a certain phrase, where he turned out to be wrong, and how the intervening 150 years have changed our theories. His account is a welcome tool for those who’d like to hear evolution from Darwin himself but find the master impenetrable.” In this brief interview, Reznick talks about the initial response to On the Origin of the Species and why it continues to be such an important book. He also has a few suggestions for how to celebrate Darwin Day this year. If you are in Calgary, David will present the 26th Annual Darwin Lecture tonight.

Princeton Global Science: You make the point that in spite of being one of the most important books ever written and being cited thousands of times, The Origin of the Species is a rather difficult book to read, right?

David Reznick: Yes. Also, it is cited far more often than it is read, I think. The difficulty lies in part in its being rooted in the science of 1859, so some of the ways he presents things are foreign. A second reason is that he had a much broader command of science than most people do today, so he skips lightly from geology to paleontology to comparative embryology to anatomy, etc.

PGS: Do you mean that the public at large had a broader command of science or that scientists were more inter-disciplinary?

DR: I actually mean both. Scientists have tended to become more and more narrow in their areas of specialization as science has grown. Darwin could be up on all of geology and the life sciences, but no one today can do so because there is now so much more to know. The general public can certainly have a better appreciation of what science is and of what evolution is.

PGS: How was The Origin of the Species received at the time it was written? Did people understand just how important this book was and would be for future scientists?

DR: Yes, it was received as a major contribution from the very beginning. Darwin already had a good reputation as a scientist and was well known to the general public because of his “Voyage of the Beagle”, so the book was taken seriously. It was also as controversial from the start as it is today. It was quite successful in making the case for evolution, but less so for natural selection.

PGS: I thought the case for evolution and the case for natural selection were one and the same. Can you explain this further?

DR: Actually, they are not. There was a long history to evolution that preceded Darwin. His grandfather wrote about it in the 18th century. Lamarck proposed a theory of evolution in the early 19th century. A widely read popular science book published in 1844 entitled Vestiges of the Natural History of Creation proposed a theory of evolution as well. Its reception by the scientists of the day was like our reception of tales of the abominable snowman and alien abductions, but it still got people thinking about evolution. It can be said that these predecessors prepared the way for Darwin. He brought much more coherent and extensive science to bear on the problem. Plus he proposed a mechanism that causes evolution, which was natural selection. In this regard, the two were separable from the start.

The fault with natural selection is that it assumed inheritance. In a later book (Variation under Domestication) Darwin proposed a mechanism of inheritance that was soon proven to be wrong. The way many people thought inheritance worked was inconsistent with natural selection.
When Mendel’s principles were rediscovered in 1900, they too were thought to be inconsistent with evolution by natural selection and were at first used as an argument against it.

PGS: How did Darwin deal with the controversial reception of his book?

DR: He did not engage in public debate nor did he generally respond to bad reviews. He corresponded extensively with others who were more than happy to defend him, like Thomas Huxley in UK and Asa Gray in the US. He also published books that promoted his ideas. He released a revision of the Voyage of the Beagle in 1860 in which he rewrote his observations and how they influenced him in a way that accommodated his later discovery of evolution.

In 1861 he published a book on fertilization in orchids in which he did an end run on those who argue that nature is too complex and beautiful to be the product of natural selection. He showed that the complexity of mechanisms by which orchids are fertilized and the complexity of their flowers can easily be explained by natural selection. He later published The Descent of Man, where he applied his principles to human evolution. There he especially expanded on sexual selection, which he proposed in Chapter 6 of the Origin. He also published the two-volume The Variation of Animals and Plants under Domestication, which is a giant expansion on Chapter 1 of the Origin.

Incidentally, while Huxley was a staunch defender of evolution, he was not a fan of natural selection. Michael Ruse looked up all of his final exams at what is now UC London and found that he never asked a question about it.

PGS: What is one of the largest misconceptions about The Origin of the Species?

DR: Well, there are many. One is that some scientists today argue that Darwin promoted sympatric speciation as the sole mechanism of speciation and competition as the sole mechanism of natural selection. He promoted both, but also presented a diversity of other ideas. You can find this point made in one of the reviews of my book<, written by my competitor who wrote The Annotated Origin for Harvard U. Press.
Another, promoted by Ernst Mayr, is that the book is really not about the origin of species, but rather is just about variation and natural selection. Mayr is guilty of applying a 1942 definition of species to a book written in 1859. He was a better biologist than historian.

PGS: Were any of Darwin’s theories later proven incorrect?

DR: He argued correctly that evolution did not cause progress, except in one regard, which is that descendent species would always be in some way superior to those of that they replaced. The idea was that descendent species drove their ancestors to extinction. He argued that you could not see the superiority just by looking at them, but that if you could in some way bring the animals of the past into interaction with the animals of today, that the contemporary fauna would “annihilate” them.

He may have been correct in principle, but our new knowledge about mass extinction dictates that the pattern of replacement is different from what he imagined.
Secondly, he was dead wrong on how inheritance works, as were all others before 1900 except Gregor Mendel. It was the absence of a known mechanism for inheritance that played a big role in the rejection of natural selection as the mechanism for evolutionary change before 1930.

PGS: Why is reading The Origin of the Species as important (more important) now than at any point in history?

DR: First, it remains a very lucid explanation of evolution as a theory, meaning as a unifying concept for the life sciences. While not intended as such, it is a potent argument against creationism and intelligent design, which is why they continue to focus their arguments on the Origin. One interesting feature that distinguishes it from modern books on evolution is the scope of science that is well explained. A final reason is that it gives you a good appreciation for the growth of ideas in science. Features of the Origin are certainly dated, but once you understand the Origin you can also appreciate how it became a guiding light for so much science that followed. Right or wrong, it did more than any one work to shape the way the life sciences were pursued thereafter. If you understand the Origin, then you can see how this happened. It also lead to the origin of new disciplines, such as branches of statistics that deal with individual variation, genetics (the Origin stimulated interest in inheritance that lead to Mendel’s rediscovery), quantitative genetics and population genetics.

PGS: What is your favorite anecdote or story about Darwin?

DR: His father saying that he would amount to nothing and be an embarrassment to his family. This occurred when he returned from medical school in Edinburgh at the age of 18 and announced that he did not want to be a doctor.

PGS: And now people are celebrating his birthday two hundred and one years later. Speaking of which, how would you recommend people celebrate Darwin Day?

DR: Well, buy my book so you can understand the Origin. To be less self-serving, I would say buy a copy of the later edition of the Voyage of the Beagle. It is very interesting and readable, but also is a window to how Darwin developed his theory. The catch is that the copy you buy will likely be the revision published in 1860. It thus postdates Darwin’s publishing of the Origin and contains many revisions not seen in the 1838 edition.