From Emerald Planet to Eden with Prof. Beerling

Making Eden by David Beerling, 2019. Oxford University Press.

Almost 12 years ago I reviewed David Beerling’s previous book The Emerald Planet. I was very impressed with that slim, but information-packed, volume; I’m even more impressed with his latest tome, Making Eden.

Yes, Making Eden has a rather straightforward message: How plants transformed the bare planet we call Earth into something approaching the Garden of Eden of holy book fame. But, Beerling tells that tale with great style and a most impressive encyclopaedic mastery of the many disciplines that contribute to that story, botany, palaeontology, geochemistry, climatology, plate tectonics, ecology, pedogenesis, etc.. This story has been hundreds of millions of years in the making, but could 2019 be the year when its message is heard, understood, and heeded? When people truly begin to take plants seriously and appreciate not only that they’ve helped us get to be what and where we are today, but can also continue to help to keep us on the planet for many more years to come – if we truly understand, respect and look after them. Certainly, Making Eden has a very good go at getting that message across.

Making Eden begins with this dramatic sentence: “The spectacular rise and diversification of plant life on land reshaped the global environment, and the possibilities of our lives. It was one of the greatest revolutions in the history of life on Earth”. And ends (well, on the penultimate page) with this reminder that: “We are completely dependent on plants now and will be in the future”.

In between, Beerling develops this remarkable story: In Chap. 1, All flesh is grass, we get Beerling’s musings on plant blindness (and an overview of the chapters that follow); Chap. 2, Fifty shades of green, and a reminder that the assault upon the land came from freshwater, not the oceans, by a charophyte ancestor; Chap. 3, Genomes decoded, in which the remarkable prescience of Nature is revealed in evidence that a genetic predisposition for land-dwelling was already present in the Plant Kingdom’s charophyte ancestor before the move to land was made; Chap. 4, Ancient genes, new plants, where – amongst many other insights – we learn what DELLA proteins are, and of their important role in the food-security-securing aspiration of the 20th century’s ‘Green Revolution’; Chap. 5, Gas valves, and a reminder that stomata are found in the fossil plant Cooksonia, which is c. 418 million years old, and therefore developed before leaves or roots(!); Chap. 6, Ancestral alliances, a much-needed reminder of the importance of plant-fungi (and plant-bacteria) associations, and another reminder* that the genetic predisposition that facilitated this association was already present in the land plant’s ancestor [But, considering the importance of plant-fungal connections, I was surprised to note that the woodwide web isn’t mentioned by name…well, it’s certainly not in the index!]; Chap. 7, Sculpting climate, with fascinating insights into how the activities of trees and forests (with fungal co-operation…) regulate rock-weathering, and the impact that has on global nutrient cycling and climate; and Chap. 8, Eden under siege, with its stark warning about biodiversity loss and our own ability to survive…

Recognising that the story he tells is our – current (!) – best ‘guess’ of how evolution of plant life on land unfolded, Beerling is keen to give the evidence and uncover the thinking behind the statements he makes. In that way, he gives important insights into the scientific method and the process and progress of science. Importantly, he considers the nature of evidence, and the importance of experiments to gain evidence to support one view or another. And, as has become his trademark (well, it’s certainly a trait that featured in his The Emerald Planet), here Beerling includes information about the scientists who’ve made the discoveries and helped to not only put the jigsaw puzzle together, but have actively found some of the pieces. And I find that to be a nice touch; after all, science is done by humans with all their quirks and foibles…

Making Eden is also a great primer (pun acknowledged…) for the more molecular side of plant biology; for example, it provides very good explanations of what are organisms’ genomes, and transcriptomes. But Beerling also provides more depth – although not every tiny, nuanced detail – about molecular-genetic events, e.g. he gives illustrative examples of how genes and their products relate to stomatal function, development, and evolution. Beerling has the knack of getting over the intricacies of gene action – especially the relevance of so-called ‘evo-devo’ to an understanding of the origins of the complexity within the plant kingdom. And by way of underlining the up-to-dateness of that whole molecular under-pinning of the colonization of land saga, a preprint by Nicole van’t Wout Hofland et al. examines the “Evolution of vascular plants through redeployment of ancient developmental regulators” , and Clémence Bonnot et al’s published paper concludes that “Neofunctionalisation of basic helix−loop−helix proteins occurred when embryophytes colonised the land” . Such ‘repurposings’ of ancient genes and developmental networks are viewed as one of the keys to the success of the land-conquering journey of plants. If, like me, you’ve tended to ‘switch off’ whenever genes and molecular biology of plant development are mentioned, then give Making Eden a try, you might be pleasantly surprised at how sensible it can be(!).

Making Eden works on so many levels, and is a really great little book. I can’t find anything to dislike about it. What more can I say? Well, I can reflect on the author’s aim in writing this book that “it might at least give readers pause for thought before dismissing botany as boring and irrelevant. I also hope that it might persuade readers to think of plants, and the scientists who study them, in an entertaining new light. … Plants and botany are in need of greater advocacy”. And, what better plant advocate could you wish for than David Beerling? Given the importance of this story, it deserves a much wider audience than its likely readership for an academic publisher’s book. Maybe this book – like The Emerald Planet – will be made into – or at least ‘inspire’… – a TV series where it may yet reach that so-important wider audience..?

Summary

Making Eden is an amazing story that is very well told by David Beerling. It should be on the reading list of every course in plant biology**. It should also be essential reading for all those in positions of influence regarding current and future agriculture and environmental policies. Whatever your own particular branch of plant biology, you’ll almost certainly learn a lot – and in a quite effortless way – about other branches of botany, and natural history more widely. I know I did. And, if you haven’t yet got the importance of the book’s message, let’s just repeat the author’s words: “Humanity’s future hinges on how we treat the extraordinary green legacy of those early land dwellers that adapted to life out of water half a billion years ago”.


* Yes, there are a lot of ‘reminders’ here. That’s because this story has been told before, by other authors in other places (e.g. by Joseph Armstrong in How the Earth Turned Green: A Brief 3.8-Billion-Year History of Plants. But, we – constantly – need to be reminded of its importance.

** Making Eden should also be on the reading list for every course in algal, animal, fungal, bacterial, and archaeal biology (and those for protozoa and oomycetes, and all the other taxa not mentioned…).

Further reading

Bonnot, C., Hetherington, A. J., Champion, C., Breuninger, H., Kelly, S., & Dolan, L. (2019). Neofunctionalisation of basic helix−loop−helix proteins occurred when embryophytes colonised the land. New Phytologist. https://doi.org/10.1111/nph.15829

Van ’t Wout Hofland, N., Lu, K.-J., Mor, E., Mutte, S., Abrahams, P., Kato, H., … De Rybel, B. (2019). Evolution of vascular plants through redeployment of ancient developmental regulators. https://doi.org/10.1101/650358