Plant Cuttings

Nature’s greatest success: How plants evolved to exploit humanity by Robert N Spengler III, 2025. University of California Press.

Nature’s greatest success by Robert N Spengler III [which tome is here appraised] is an important book.

Background

The prevailing popular and populist view regarding the origins of agriculture – or, even “the invention of farming” or the “invention of agriculture” (Simon Barnes The history of the world in 100 plants, pages 12, 79, 80, 98) – is that humans developed it about 12,000 – 10,000 years ago, and is known as the Neolithic Revolution (Erin Blakemore), Agricultural Revolution, or First Agricultural Revolution (Irene Park). In other words, and recognising that “domestication of plants and animals was a turning point for humanity” (p. vii), this view of history puts people very much in the driving seat, consciously and deliberately taming plants and bending them to humanity’s will.

But, what if that’s not actually the case? What if, instead, it was the other way round – with plants setting the pace and dictating the terms upon which they ‘allowed themselves’ to be domesticated? That alternative view is the essence of Spengler’s thesis, domestication – a necessary precursor to development of agriculture – was an inevitable consequence of the evolutionary development of some plants (and some animals). Humanity just worked with what nature had already provided. Although in that scenario, domestication is an unconscious act on the part of humans, it has resulted in one of – arguably, the – greatest plants-and-people partnerships in the history of humanity. Why? Because “farming of reliable domesticated plants created food surpluses that permitted demographic growth, and, eventually, the development of social complexity” (p. viii).

Book’s bold aim…

Accordingly, in Nature’s greatest success, Spengler sets himself no less a challenge than to “attempt to convince you that all the stories you have been told about the origins of agriculture are fictitious. Agriculture was not a sudden innovation, and it was not a response to push or pull factors. Domesticated crops and animals were not invented by early humans” (p. 1) [Ed. – it’s probably important to say that Spengler acknowledges that humanity only began to direct domestication when it understood and undertook conscious, deliberate, directed breeding of plants and animals, during the last few centuries]. Although the notion that plants played a major role in influencing people to the extent that they cultivated several crops – e.g. potatoes, cannabis, apples, and tulips – for the benefit of the plants may be familiar to us from Michael Pollan’s book The botany of desire, Spengler takes that notion to the next level. In Nature’s greatest success, Spengler examines the case that “domestication is inevitable, and … began unintentionally and unconsciously” (p. 399). In doing so he presents a closely-, and carefully-, argued, highly-detailed, source-supported, analysis of the evidence in favour of his thesis.

What sort of book is it?

Nature’s greatest success is undoubtedly an academic book replete with evident great scholarship on the part of the author. Accordingly, Spengler supports his argument with more than 1,170 foot notes*. However, the quite challenging nature of the text** is made more palatable by Spengler’s great writing style***, and the fact that the text is punctuated with 50 figures**** and 4 tables, and broken-up with sub-headings within each of the book’s 15 chapters [Ed. – all of which characteristics appear to be hallmarks of a ‘Spengler book’ as seen previously in Fruit from the sands]. And further help is at hand with a conclusion at the end of most of the chapters. Spengler engages in abundant repetition throughout the text. But, rather than be annoying, one should view that as reinforcement of his central idea. That then becomes a legitimate pedagogic technique; Spengler is, after all, trying to teach us a new way to think about domestication. And it’s important to recognise that Nature’s greatest success isn’t just about plants, there’s much here regarding the domestication of animals – which arguably underlines the generality of the phenomenon. There is therefore plenty in the book to appeal to those who like a good plants-and-people story, and those who like to understand more about animals and people, too. As readers of this blog will know, I’m very much a ‘plant person’, but for all of my botanical allegiance I am grateful to Spengler for the opportunity to learn a great deal about animals*****.

In building his case, Spengler draws upon research from many disciplines, and uses examples both of plants and animals to underline his central message that domestication is an inevitable outcome of evolution – and not a consequence of human intervention [Ed. – if readers are detecting some repetition of this notion, it’s because it’s happening, and is an example of the reinforcement of Spengler’s central idea as used in the book…]. Whilst this reviewer found his arguments compelling and convincing, Spengler does acknowledge that others may not. That awareness is evident when he says that “I do not proclaim to have all the answers in the pages that follow, and I expect that this book will eventually be allotted to the library annex or a digital archive as science rapidly advances. However, if I succeed in encouraging you to think critically about how apples or wheat came to be and the role of humanity in the process, I have achieved my goal” (p. ix). In this reviewer’s view he has certainly achieved that.

The nearly 500 pages of argument and defence of Spengler’s notion in Nature’s greatest success is admirably – and succinctly – summarised in the book’s sub-title, How plants evolved to exploit humanity******.

Recognising the debt…

With all of its impressive scholarship and erudition, Spengler is humble and honest enough to generously acknowledges the debt he owes to those who preceded him. Those scene-setting pioneers include Charles Darwin and his influential book from 1868, The variation of animals and plants under domestication, and more contemporary scientists – in particular, David Rindos (and his book The origins of agriculture: an evolutionary perspective), and Daniel Janzen – whose work has helped to influence Spengler’s own ideas about domestication.

Summary

Spengler’s goal in Nature’s greatest success is surprisingly simple and straightforward, to persuade the readers that domestication is not something that humans have consciously and purposefully visited upon plants (or animals). Rather, it is very much a partnership in which the plants have domesticated people as much as anything the other way round. He hopes to succeed in encouraging the reader “to think critically about how apples or wheat came to be and the role of humanity in the process” (p. ix). This reviewer thinks he has. In changing the reader’s mindset about domestication and the origins of agriculture, Nature’s greatest success is an important book, and a welcome addition to the plants-and-people genre.

* Although, as thoroughly well-researched and evidence-based as Spengler’s main arguments are and defence of his central thesis is, many of his more peripheral statements aren’t so suitably source-supported. For example, it would be good to know the evidence for saying that: “Ginseng is the most widely poached plant in North America” (p. 70); “woody plants tend to lack secondary defensive compounds” (p. 186); “The Earth is 4.543 billion years old” (p. 396), and “life has existed here for 3.5 billion years” (p. 396).

** Technical terms used without explanation include: epigenetic inheritance; phenotypically (p. 6) (although phenotype is defined later, on p. 29…); introgression; developmentally plastic; heterosis (p. 48) (although defined as ‘hybrid vigor on p. 96); polymorphic; mtDNA; stochastic forces; monogastric megafaunal mammals; ungulate megafaunal mammals; proboscideans (notably gomphotheres); megalonychids; megatheriids; and sympatric populations. Which is compounded by use of several non-English phrases – without translation or explanation, e.g., “salto morale” (p. 21), “vox clamantis in deserto” (p. 88), “culte, deification de l’humanité” (p. 89), and the title of chapter 10, Natura non facit saltum.

But, for me as a botanist, the most challenging piece of text was reading that Echinochloa grass “is among a handful of plants that have evolved a different form of respiration [Ed. – yes, respiration]” (p. 229). I do not understand what Spengler means here, and no source is supplied that I could refer to in order to understand what he means. However, he goes on to state “These plants, which biologists call C4 plants [Ed. – Echinochloa is a genus of C4 plants], have an increased ability to breathe in certain ecosystems, notably in the southern latitudes and in conditions of low atmospheric carbon” (p. 229). Which makes me wonder if Spengler is referring to a different form of photosynthesis rather than respiration [Ed. – although one acknowledges that one of the traits of C4 photosynthetic plants is a much lower rate– or even elimination of – photorespiration (Andrea Bräutigam & Udo Gowik, 2016; John Kimball)]. But, my initial state of bafflement is compounded by Spengler going on to say, “C4 photosynthesis provides immense advantages to the plants that evolve this ability, analogous to the evolution of air-breathing lungs in animals [my emphasis] except that the C4 photosynthetic pathway evolved independently several times in plants” (p. 230). All rather odd, but fortunate that it does not really affect the book’s overall argument in favour of ‘unconscious domestication’.

*** Who surely cannot fail to appreciate one who writes with such phrasing as: “Thus, humans did not choose the crops – the plants auditioned for the role of crop” (p. 39); “a robust understanding of the role of cars in driving evolution” (p. 64); “… a young zoologist specializing in Bovidae took the bull by the horns …” (p. 121); “The cat chased the mouse into domestication” (p. 158); and “the idea that only naturally docile creatures became domesticated is complete bollocks” (p. 386).

**** All the book’s 50 illustrations are black-and-white pictures, which makes it a little disappointing when one sees a legend that talks about “bright yellow fruits” (p. 278). Although all figures are rather small, they occasionally show enlarged views of small features of plants. It would greatly assist the reader’s interpretation and understanding of such images if they consistently included scale bars so the actual sizes can be appreciated. However, when shown, it is sometimes hard to fully understand what a scale bar is showing, e.g., Fig. 50 (p. 390); regarding panel a, does the scale bar only apply to the magnified inset? In respect of panels b and c, there is no indication of what length the scale bar represents. Although all figures have legends or explanatory notes, it is hard to know what to make of this comment “These fossils clearly indicate the fact that peaches evolved to be too large for dispersal by birds or small mammals” (Fig. 40, p. 299), even if a scale bar had been supplied. The scale bar in Fig. 48 (p. 338) appears to be doing a good job, however.

***** I learnt lots of interesting facts from the book. For example, that: there is probably no such thing as a wild wolf; “These statistics make deer the single most dangerous animal in America” (p. 63); “the tortoises could enter the category of the earliest domesticated animal on the planet” (p. 68); it takes the trash and human faeces of 14 people to feed one feral street dog; there are one billion dogs on the planet; “there is good reason to believe that some populations of hyenas in Africa and polar bears in Alaska are on a path toward domestication as they take on the role of dump-heap foragers and become isolated from their wild relatives” (p. 386) [Ed. – I said the book contained a lot of information about animals!].

Spengler’s book also introduced me to the existence of: the oasis model, the broad-spectrum foraging theory, failure-to-domesticate paradox, Sauer’s river floodplain hypothesis for the origination of agriculture, Robert Sussman’s angiosperm-primate coevolution theory, the frugivory hypothesis, the extinct Pleistocene megafauna hypothesis, and the foliage-as-fruit hypothesis.

And – although Spengler provided no references for this statement – I was interested to learn that Danish biologist Willhelm Johannsen first coined the term ‘gene’, in 1909 (Nils Rolls-Hansen, 2014; Joan C Stevenson) [Ed. – in researching that fact I discovered that, and chronologically curiously, William Bateson had earlier introduced the word ‘genetics’ in 1905/6 (Howard D Lipshitz, 2021)…]

****** If you like to read more of what Spengler has to say – for free – his main argument about the nature of domestication is stated in the freely-accessible publication Robert N. Spengler et al., 2025. And there’s more on the whole domestication topic in in the Philosophical Transactions of the Royal Society B special issue entitled “Unravelling domestication: multi-disciplinary perspectives on human and non-human relationships in the past, present and future”.

REFERENCES

Andrea Bräutigam & Udo Gowik, 2016. Photorespiration connects C₃ and C₄ photosynthesis. Journal of Experimental Botany 67(10): 2953–2962; https://doi.org/10.1093/jxb/erw056

Howard D Lipshitz, 2021. The origin of genetics. Genetics 217(1): 1-2; doi: 10.1093/genetics/iyaa024

Nils Roll-Hansen, 2014. The holist tradition in twentieth century genetics. Wilhelm Johannsen’s genotype concept. J Physiol 592(11): 2431-2438; doi: 10.1113/jphysiol.2014.272120

Robert N Spengler et al., 2025. Seeking consensus on the domestication concept. Phil. Trans. R. Soc. 380(1926): B38020240188; http://doi.org/10.1098/rstb.2024.0188