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Introduction

Let’s say that we either use a machine to teleport to another reality where Darwin didn’t exist or one where he died early, before formulating the theory of natural selection (ToNS). Would our evolutionary knowledge suffer? Under what pretenses could we say that our evolutionary knowledge wouldn’t suffer? Well, since Darwin humbly stated that what he said wasn’t original and that he just assembled numerous pieces of evidence to cohere to make his ToNS, then obviously we know that species changed over time. That’s what evolution is—change over time—and Darwin, in formulating his ToNS, attempted to prove that it was a mechanism of evolutionary change. But if Darwin never existed or if the ToNS was never formulated by him, I don’t think that our evolutionary knowledge would suffer. This is because people before Darwin observed that species change over time, like Lamarck and Darwin’s grandfather, Erasmus Darwin.

So in this article I will argue that had Darwin not existed or died young and had not formulated the ToNS, we would still have adequate theories of speciation, trait fixation and evolutionary change and processes, since naturalists at the time knew that species changed over time. I will discuss putative mechanisms of evolutionary change and show that without Darwin or the ToNS that we would still be able to have coherent theories of speciation events and trait fixation. Mechanisms like genetic drift, mutation and neutral evolution, environmental constraints, Lamarckian mechanisms, epigenetic factors, and ecological interactions would have been some plausible mechanisms sans Darwin and his ToNS even in the modern day as our scientific knowledge advanced without Darwin.

What if Darwin never existed?

For years I have been critical of Darwin’s theory of natural selection as being a mechanism for evolutionary change since it can’t distinguish between causes and correlates of causes. I was convinced by Fodor’s (2008) argument and Fodor and Piattelli-Palmarini’s (2010) argument in What Darwin Got Wrong that Darwin was wrong about natural selection being a mechanism of evolutionary change. I even recently published an article on alternatives to natural selection (which will be the basis of the argument in this article).

So, if Darwin never existed, how would the fact that species can change over time (due to, for instance, selective breeding) be explained? Well, before Charles Darwin, we had his grandfather Erasmus Darwin and Jean Baptiste Lamarck, of Lamarckian inheritance fame. So if Charles Darwin didn’t exist, there would still be enough for a theory of evolution had Darwin not been alive to formulate the ToNS.

We now know that Charles did read Erasmus’ The Temple of Nature (TToN) (1803) due to the annotations in his copy, and that the TOnF bore resemblance not to Darwin’s On the Origin of Species, but to The Descent of Man (Hernandez-Avilez and Ruiz-Guttierez, 2023). So although it is tentative, we know that Charles had knowledge of Erasmus’ writings on evolution. But before TToN, Erasmus wrote Zoonomia (1794), where he proposed a theory of common descent and also speculated on the transmutation of species over time. Being very prescient for the time he was writing in, he also discussed how the environment can influence the development of organisms, and how variations in species can arise due to the environment (think directed mutations). Erasmus also discussed the concept of use and disuse—where traits that an organism would use more would develop while traits they would use less would diminish over time—which was then a pre-cursor to Lamarck’s thoughts.

An antecedent to the “struggle for existence” is seen in Erasmus’ 1794 work Zoonomia (p. 503) (which Darwin underlined in his annotations, see Hernandez-Avilez and Ruiz-Guttierez, 2023):

The birds, which do not carry food to their young, and do not therefore marry, are armed with spurs for the purpose of fighting for the exclusive possession of the females, as cocks and quails. It is certain that these weapons are not provided for their defence against other adversaries, because the females of these species are without this armour. The final cause of this contest amongst the males seems to be, that the strongest and most active animal should propagate the species, which should thence become improved.

Jean Baptiste Lamarck wrote Philosophie Zoologique (Philosophical Zoology) in 1809. His ideas on evolution were from the same time period as Erasmus’, and they discussed similar subject matter. Lamarck believed that nature could explain species differentiation, and that behavioral changes which were environmentally induced could explain changes in species eventually leading to speciation. Lamarck’s first law was that use or disue would cause appendages to enlarge or shrink while his second law was that the changes in question were heritable. We also know that in many cases that development precedes evolution (West-Eberhard, 2005; Richardson, 2017) so these ideas in the modern day along with the observations to show they’re true also lend credence to Lamarck’s ideas.

First Law: In every animal that has not reached the end of its development, the more frequent and sustained use of any organ will strengthen this organ little by little, develop it, enlarge it, and give to it a power proportionate to the duration of its use; while the constant disuse of such an organ will insensibly weaken it, deteriorate it, progressively diminish its faculties, and finally cause it to disappear.

Second Law: All that nature has caused individuals to gain or lose by the influence of the circumstances to which their race has been exposed for a long time, and, consequently, by the influence of a predominant use or constant disuse of an organ or part, is conserved through generation in the new individuals descending from them, provided that these acquired changes are common to the two sexes or to those which have produced these new individuals (Lamarck 1809, p. 235). [Quoted in Burkhardt Jr., 2013]

Basically, Lamarck’s idea was that acquired traits during an organism’s lifetime could be passed onto descendants. If an organism developed a particular trait in response to its environment, then that trait could be inherited by its descendants. He was also one of the first—along with Erasmus—to go against the accepted wisdom of the time and propose that species could change over time and that they weren’t fixed. Basically, I think that Lamarck’s main idea was that the environment could have considerable effects on the evolution of species, and that these environmentally-induced changes could be heritable.

Well today, we have evidence that Lamarck was right, for example with the discovery and experiments showing that directed mutation is a thing. There was a lot that Lamarck got right and which has been integrated into the current evolutionary theory. We also know that there is evidence that “parental environment-induced epigenetic alterations are transmitted through both the maternal and paternal germlines and exert sex-specific effects” (Wang, Liu, and Sun, 2017). So we can then state Lamarck’s dictum: environmental change leads to behavioral change which leads to morphological change (Ward, 2018) (and with what we know about how the epigenetic regulation of the transposable elements regulates punctuated equilibrium, see Zeh, Zeh, and Ishida, 2009, we have a mechanism that can lead to this). And since we know that environmental epigenetics and transgenerational epigenetic provides mechanisms for Lamarck’s proposed process (Skinner, 2015), it seems that Lamarck has been vindicated. Indeed, Lamarckian inheritance is now seen as a mechanism of evolutionary change today (Koonin, 2014).

So knowing all of this, what if Charles Darwin never existed? How would the course of evolutionary theory be changed? We know that Darwin merely put the pieces of the puzzle together (from animal breeding, to the thought that transmutation could occur, etc.), but I won’t take anything away from Darwin, since even though I think he was wrong on a mechanism of evolution being natural selection, he did a lot of good work to put the pieces of the puzzle together into a theory of evolution that—at the time—could explain the fixation of traits and speciation (though I think that there are other ways to show that without relying on natural selection). The components of the theory that Darwin proposed were all there, but he was the one that coalesced them into a theory (no matter if it was wrong or not). Non-Darwinian evolution obviously was “the in thing” in the 19th century, and I don’t see how or why it would change. But Bowler (2013) argues that Alfred Russell Wallace would have articulated a theory of nature selection based on competition between varieties, not individuals as Darwin did. He argues that an equivalent of Darwin’s ToNS wouldn’t have been articulated until one recognized the similarities between what would become natural selection and artificial selection (where humans attempt to consciously select for traits) (Bowler, 2008). Though I do think that the ToNS is wrong, false, and incoherent, I do recognize how one would think that it’s a valid theory in explaining the evolution of species and the fixation of traits in biological populations. (Though I do of course think that my proposed explanation in linking saltation, internal physiological mechanisms and decimationism would have played a part in a world without Charles Darwin in explaining what we see around us.)

Now I will sketch out how I think our understanding of evolutionary theory would go had Charles Darwin not existed.

Although Lamarckism was pretty much discredited when Darwin articulated the ToNS (although Darwin did take to some of Lamarck’s ideas), the Lamarckian emphasis of the role of the environment shaping the traits of organisms would have persisted and remained influential. Darwin was influenced by many different observations that were known before he articulated his theory, and so even if Darwin didn’t exist to articulate the ToNS, the concept that species changed over time (that is, the concept that species evolved) was persistent before Darwin’s observations which led to his theory, along with the numerous lines of evidence that led Darwin to formulating the ToNS after his voyage on The Beagle. So while Darwin’s work did accelerate the exceptance of evolution, it is therefore very plausible that other mechanisms that don’t rely on selection would have been articulated. Both Erasmus and Lamarck had a kind of teleology in their thinking, which is alive today in modern conceptions of the EES like in that of arguments forwarded by Denis Noble (Noble and Noble, 2020, 2022) Indeed, Lamarck was one of the first to propose a theory of change over time.

Punctuated equilibrium (PE) can also be integrated with these ideas. PE is where rapid speciation events occur and then there is a period of stasis, and this can then be interpreted as purposeful evolutionary change based on the environment (similar to directed mutations). So each punctuated episode could align with Lamarck’s idea that organisms actively adapt to specific conditions, and it could also play a role in explaining the inheritance of acquired characters. So organisms could rapidly acquire traits due to environmental cues thsg the embryo’s physiology detects (since physiology is homeodynamic), there would be a response to the environmental change, and this would then contribute to the bursts of evolutionary change. Further, in periods of stasis, it could be inferred that there would be really no changing in the environment—not enough anyway, to lead to the change in the traits of a species—and so organisms would have been in equilibrium with their environment minting the traits until a new change in the environmental challenges triggered a burst of evolutionary change which would kick the species out of stasis and lead to punctuated events of evolutionary change. Therefore, this model (which is a holistic approach) would allow for a theory of evolution in which it is responsive, directed, and linked with the striving of organisms in their environmental context.

Conclusion

So in a world without Charles Darwin, the evolutionary narrative would have been significantly shaped by Erasmus and Lamarck. This alternative world would focus on Lamarckian concepts, the idea of transmutation over time, purposeful adaptation over time along with directed mutations and the integration of PE with these other ideas to give us a fuller and better understanding of how organisms change over time—that is, how organisms evolve. The punctuated episodic bursts of evolutionary change can be interpreted as purposeful evolutionary change based on Lamarckian concepts. Environmental determinism and stability shape the periods between bursts of change. And since we know that organisms in fact can adapt to complex, changing environments due to their physiology (Richardson, 2020), eventually as our scientific knowledge advanced we would then come to this understanding.

Therefore, the combination of Erasmus’ and Lamarck’s ideas would have provided a holistic, non-reductive narrative to explain the evolution of species. While I do believe that someone would have eventually articulated something similar to Darwin’s ToNS, I think that it would have been subsumed under the framework of built off of Erasmus and Lamarck. So there was quite obviously enough evolutionary thought and ideas before Darwin for there to be a relevant and explanatory theory of evolution had Darwin not been alive to formulate the ToNS, and this shows how such mechanisms to explain the origin of life, speciation, and trait fixation would have occurred, even in the absence of Darwin.