Reviews

Plants: Animated, dynamic, and mobile(!)

How do plants travel? A new book explains.

The Incredible Journey of Plants, by Stefano Mancuso 2020. Other Press.

What do you get if you combine Frank Capra’s film “It’s a wonderful life” with Michael Pollan’s The Botany of Desire and What a Plant Knows by Daniel Chamovitz? Stefano Mancuso’s latest book The Incredible Journey of Plants [hereafter called Plant Journey].

For some who work in the world of plants mention of Stefano Mancuso’s name is enough to elicit a knee-jerk – and rather negative – reaction because of his association with the concept of plant neurobiology and notions of plant intelligence. Both of which terms are considered controversial by some commentators creating claim and counter-claim in the literature (e.g. David Robinson et al., EMBO Rep (2020)21:e50395; František Baluška and Stefano Mancuso, EMBO Rep (2020)21:e50495; ). Although Mancuso’s previous books Brilliant Green [with Alessandra Viola] and The Revolutionary Genius of Plants have developed his ideas of plant intelligence, there should be little controversy with the contents of the book considered here. Indeed, almost all of Plant Journey* should be acceptable to those with the capacity to appreciate the impressive ways that plants survive and thrive in a world that is often hostile to living things.

In essence, Plant Journey takes what is probably the major distinction between plants and animals – that the former can’t move about – and demonstrates in its 147 pages just how pre-eminently mobile plants actually are. So much so that the impulse to move “…has driven plants to colonize every possible environment on Earth” (p. xv). Accordingly, the incredible journeys described in the book involve plants as pioneers, combatants, veterans, fugitives, conquerors and time travellers. Using such active words, the book’s emphasis is very much on plants as dynamic, vital, and animated living entities: How refreshing!

Although aimed at a general audience, Mancuso doesn’t avoid some quite technical topics, such as the concept of evolutionary anachronism [“attributes of living species that are best explained as a result of having been favorably selected in the past due to coevolution with other biological species that have since become extinct”]. But, pleasingly – and, with the benefit of having read the whole book, typically – Mancuso does so in a seemingly effortlessly comprehensible way with particular reference to the avocado (Persea americana). Historically, the large fruit-enclosed seed of this plant was believed to be spread by south American megafauna such as the Gomphotherium and Glyptodon. But presumed over-exploitation of these animals by humans left the plant without its natural seed-dispersers, and the species was seemingly similarly doomed to suffer extinction. How fortunate then that the extant jaguar appeared to do a reasonable job in replacing the extinct megafauna, before humanity saved the avocado from terminal and fatal decline because of its culinary and dietary desirability. The journey of Persea americana, from food of long-extinct megafauna to seedless cocktail avocados (!), is one of several entertaining and informative plants-and-people tales of Plant Journey.

Some other intriguing vegetable** stories are the account of the diffusion of Senecio squalidus (Oxford ragwort) from its volcanic homeland in Sicily to the walls of Oxford, and then the rest of the world, and the amazing tale of Major Frederick R Burnham, the water hyacinth (Eichhornia crassipes) and hippopotami in the US. Mancuso also has much to say about the pioneering ‘spirit’ of plants in the colonization of the geologically-newly-formed island of Surtsey, which, when eventually solidified as new land above the Atlantic Ocean, was initially uninhabited terrain of cooled ash, pumice, sand and lava. In particular he acknowledges the surprising role of fish eggs (!) in transporting seeds of flowering plants to that island (Sturla Fridriksson, Arctic and Alpine Research 19(4): 425-431, 1987;).

Not only are plants adept at finding, exploring and inhabiting new environments, they are also great survivors once established there. Accordingly, Mancuso has lots to say about plants in Chernobyl’s Zone of Alienation, and Hibakujumoku (“survivor tree or A-bombed tree in English is a Japanese term for a tree that survived the atomic bombings of Hiroshima and Nagasaki in 1945”) in Hiroshima. Which last tale also includes the humbling anecdote of the author’s meeting with the Japanese Consul to Italy in Japan: Elegant, effective and affecting writing.

One of the book’s most poignant chapters, entitled Solitary trees,*** is memorable not so much for travelling plants but for those that have come to the end of their particular journey. Solitary trees in question include the single Sitka spruce (Picea sitchensis) on Campbell Island (“lying 700 km south of New Zealand’s South Island”), and the sole example of Acacia tortilis in the desert of Ténéré (a “region of the Sahara extending from northeastern Niger into western Chad” in Africa).

The lonesome spruce of Campbell Island has at least two notable claims to fame. First, it is – now [see below] – officially the loneliest tree in the world since the nearest neighbouring member of that species is 120 miles away on the Auckland Islands (the ‘Galapagos of the Southern Ocean’, “One-third of the way from New Zealand to Antarctica”). Second, it may be witness to the advent of the Anthropocene [“Earth’s most recent geologic time period as being human-influenced, or anthropogenic, based on overwhelming global evidence that … earth system processes are now altered by humans”] (Simon Lewis & Mark Maslin, Nature 519: 171–180, 2015😉 because of the elevated amounts of 14C within its annual growth rings formed in the mid-1960s. This increase in radioactive carbon is associated with nuclear weapons’ testing in the 1950s and 1960s at the dawn of the so-called Atomic Age, one of the proposed defining events that mark the start of the Anthropocene (Chris Turney et al., Sci Rep 8, 3293 (2018)😉 – which reference is cited by Mancuso but without its DOI). The ‘acacia of Ténéré’ (apparently now known as Vachellia tortilis), was formerly the loneliest tree in the world – until its fate was sealed after two motor vehicles crashed into it, on different occasions (an absurdly impressive feat since it’s the only tree for mile after mile of otherwise tree-less desert and probably deserves to be known – if only posthumously – as the unluckiest tree in the world…).

Although recounting the impressive survival-and-resurrection story of the date palm named Methuselah*** grown from 2,000 year-old seed collected from the site of the Jewish stronghold of Masada, Mancuso is not so strong on the other meaning of the word ‘dates’. For example in talking about Roman engineering works he is impressed that some are “still standing and functioning some two hundred years after their construction” (p. 89). Surely, that should be two thousand years after their construction? Now that is impressive.

Another dating issue concerns German August Engelhardt, the nude, sun-worshipping, coconutarian who founded the Sonnenorden (‘Order of the Sun’). According to Mancuso this intriguing gentleman set up his colony for like-minded devotees in the Bismarck archipelago (in what is today Papua New Guinea), after settling there on 15th September, 1922. Yet, he was apparently found dead on a beach on 6th May 1919, i.e. over three years before his arrival. Sensing a little inaccuracy here, Googling suggests that the year in which he reached the archipelago should actually be 1902. So, 1922 is presumably just a ‘typo’ in the book – which is easier to understand than a time-travelling, naked coconut-eater(!).

Those chronological matters aside (and which relate to humans rather than the book’s real subject matter…), Plant Journey is full of great writing (e.g. the opening two sentences of Chapter 6). And not just about plants, but also people, places and historical events, and the intimate interactions between them. The text is very readable, and should be readily understandable by its intended educated lay readership. Mancuso is a natural storyteller, and he has many stories to tell: The Incredible Journey of Plants is a truly original, charming, and enjoyable collection of plant tales. A very real sense of Mancuso’s awe (which is fully justified) in, and respect for, the abilities of plants to survive and exploit otherwise inhospitable environments pervades the book, which itself is a joyous celebration and affirmation of the awesomeness and persistence of vegetable life.

For all its wonderful aspects (and they are many), the book is not without its dubious entries or errors. For instance, and although one cannot help but admire Mancuso’s enthusiasm for the marvellous migratory achievements of green life, I don’t think living plants have yet reached, let alone conquered, the deepest oceans. Nor arguably, the highest mountaintops either (unless one includes certain algae – which are within Mancuso’s definition of ‘plant’** – such as those that give rise to ‘red snow’, or that may have scaled such heights, carried aloft by air currents). If algae are permitted (and I think they should be), probably plants have also made it to polar ice caps. But, it is wrong to describe Silene stenophylla as a perennial grass. It is a type of campion, a member of the dicot family the Caryophyllaceae (as Mancuso actually acknowledges and states) not the monocotyledonous grass family, the Poaceae. And it is not acceptable to spell phosphorus as phosphorous (p. 74). Perhaps the most curious aspect of the book is the absence of an Index(!): An oversight, or deliberate ploy to encourage close reading and note-taking by the reader..?

With my eye on the book’s potential pedagogy, it is nice to see sources included – in-text numbers add extra information about, or related to, sources, e.g. books or scientific papers. Although continuous numbering is used in-text, the sources are listed under the relevant chapter at the back of book. However, several statements are not referenced [see blog item on this matter], and DOIs are missing for some of the references (where that digital object identifier is necessary to identify the specific article – e.g. Freidlander et al. (p. 153), Turney et al. (p. 156), and Schleuning et al.) (p. 158).

Although Mancuso is rightly regarded as the book’s author, we must make due reference to Gregory Conti, who has translated the author’s original Italian text into English. And what a great job he’s done! The text is not only highly readable, but includes lots of memorable phrasing (e.g. describing the city of Pripyat post-Chernobyl as “a veritable Ukrainian Angkor Wat” – although one wonders if the Ficus-festooned buildings of nearby Ta Prohm are visually closer to the vegetation-reclaimed structures of the radioactive city, rather than the relatively unenveloped site at Angkor Wat itself), and some humour. Acknowledging that something is always lost in translation, one assumes that the original Italian was also a really great read – and presumably also had memorable phrasing and humour. The only odd moment came from the phrase “in the bat of an eyelash” (p. 136) – referring to the sudden loss of megafauna from the world. Presumably ‘in the blink of an eye’ [“very quickly”] is intended there..? But, whether that choice of phrase is down to the author or the translator, we’ll probably never know.

In addition to the words, the pages of Plant Journey are adorned with numerous watercolours from the hand of Grisha Fischer – who appears to have little web presence beyond such entries as this and this (relating to her contribution specifically to the book appraised in this blog item…), which are probably best described as ‘quirky’ or ‘charming’. However, although they’re quite pleasant to look at, I’m not sure what they actually add either to the text specifically, or to the book more generally.

Summary

This is a great book. If you want to know a little more about some of the impressive lives of plants – with a good dash of geography, history and personalities as well – Stefano Mancuso’s The Incredible Journey of Plants is just the thing.


* Although there are some hints of that here. For example, in Chapter 3 – which includes the concept of parental care by plants of their progeny (Bianca A Santini& Carlos Martorell, Am J Bot 100(2): 365-373, 2013;), Mancuso’s statement that “mother plant, Mammillaria hernandezii teaches [my emphasis] its seeds …” (p. 73) is probably too anthropomorphic for some. And, is it really the case that, “These survival capsules [seeds] are so perfect in their simplicity as to make those who study them believe that seeds are endowed with supernatural qualities [my emphasis]” (p. 80)?

** Mancuso considers vegetables, for the book’s purpose, to be “organisms capable of photosynthesis” (p.2). Although why vegetable is used instead of the more broadly applicable word plant isn’t clear…

*** Mancuso acknowledges the issue with this chapter title; “Every solitary living being is in some way a contradiction in terms. For there to be life, there must be community with other living beings and, obviously, with other individuals of one’s own species” (p. 102).

**** For an update [sorry, couldn’t resist…] on the Methuselah fruit regeneration story, see Sarah Sallon et al. (Science Advances 05 Feb 2020: Vol. 6, no. 6, eaax0384;), and popular science articles by Isabel Kershner, and Sarah Zhang.

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