Steven D. Allison
Harvard University Press Out 3 November (US) and 27 November (UK)
It鈥檚 2030. Heatwaves are scorching parts of the globe, while elsewhere, hailstorms or tsunamis ravage homes, cities and farmlands. Wildfires rage across continents, Arctic ice sheets dwindle, volcanoes spew left and right, and Earth cracks open along multiple fault lines. Death tolls 鈥� human, animal and plant 鈥� soar.
Amid this doom and gloom, a superhero arises from scientific labs, ready to fight our 鈥� human-made 鈥� enemy, climate change. The tiny figure can trap excess carbon from the atmosphere, or bury it underground or at the bottom of the sea, for near-eternity. It can fuel jet engines with clean energy, replace chemical fertilisers, save coral reefs from bleaching and disease, and re-engineer trees, food crops and other plants to survive, even thrive, in droughts.
Advertisement
This scenario is at the heart of Steven Allison鈥檚 book, . Allison, professor of ecology at the University of California, Irvine, maintains a balance between realism and optimism as he introduces his as yet unsung hero, the microbe.
These resilient, highly adaptable and primarily single-celled organisms could, he insists, play a far larger role in controlling or maybe even reversing climate change than we imagine. Many of these bacteria, archaea, fungi and viruses are currently dismissed as insignificant or even targeted as pathogens to be wiped out. But the microbes he and others envision using against climate change are non-toxic and non-pathogenic.
The tiny superhero can trap excess carbon from the atmosphere or bury it underground for near-eternity
They are also, unlike other proposals 鈥� installing solar mirrors in space or sucking carbon dioxide out of the air 鈥� cheap, abundant, easy to produce and totally organic. For Allison, they 鈥渙ffer a rare glimmer of hope鈥�.
His book explores how microbes live and interact with each other, and with 鈥渘ewcomers鈥� such as humans. He focuses especially on how scientists are uncovering the mysteries of microbes and glimpsing the extraordinary properties they could offer if we only understood enough to stop fighting them.
Allison is a captivating storyteller, taking us on colourful journeys to different regions and times. Along the way, we meet fascinating characters, like Antonie van Leeuwenhoek, who ran his own draper鈥檚 shop in the Dutch city of Delft during the 17th century, and discovered bacteria by looking at his dental plaque using microscopes and lenses he had custom-built.
Microbes also appear as characters in their own right. We encounter bacteria-eating viruses engaged in an 鈥渋nsidious lifestyle鈥� known as lysogeny inside their hosts, and zooplankton, which, like cattle, graze 鈥� and 鈥減oop a lot鈥�.
He ensures we stay focused as we navigate complex concepts and vocabulary, like 鈥減hycoerythrins鈥�, light-harvesting and naturally fluorescent proteins in certain cyanobacteria. We also get better acquainted with biofilms 鈥� layers of slime made of carbohydrates, proteins and other sticky biomolecules. Unlike the ones we know and hate 鈥� dental plaque and toilet bowl rings 鈥� these biofilms stop important microbes from being swept away in moving water by holding on to water like a sponge. Those microbes are also protected from desiccation, while predators, such as animals or viruses in soil, find it hard to get at prey inside a biofilm. Inside, microbes can gain the carbon and nutrients they need to grow.
In passing, Allison provides us with what can seem like cool facts to use at dinner parties. But they are offered in service of the big picture. Did you know that Sequoia trees can live a thousand years or that their bark is fire-resistant? That the annual per capita energy usage in the US is 76,300 kilowatt-hours, equivalent to the energy in 2300 gallons of petrol? Or that there are nearly 3 billion billion billion oxygen-producing Prochlorococcus cyanobacteria floating around the ocean, thousands more than the stars in the known universe?
One way or another, the core message of The Age of Microbes is delivered: we can get microbes right or we can get them wrong. They are incredibly good at taking carbon in 鈥� and at letting it out again. The trick is to get them to swallow carbon and harbour it for thousands of years. That is exactly what they already do when their remains are preserved in the ground or at the bottom of the ocean as 鈥渕icrobial mummies鈥�, forming clumps called necromass.
Enter the other superheroes in Allison鈥檚 book: the researchers and bioengineers studying microbes. There is a refreshing amount of overdue credit given to women scientists. What we now call the greenhouse effect was discovered by Eunice Newton Foote, who published a paper on it in 1856. A century or so later, biologist Mary Mandels pioneered cellulosic ethanol using fungal enzymes. If we ever fly on jets powered by carbon-neutral fuel, Allison says, 鈥測ou鈥檒l have microbes and Mary Mandels to thank鈥�. He also pays due debt to the Earth wisdom of Indigenous peoples, including the Pacific Northwest Karuk, who understand the importance of mushroom networks.
Today鈥檚 labs are investigating the genes behind necromass, hoping to selectively breed for them or to produce 鈥渄esigner microbes鈥�. Others study how to help plants resist climate change. Still others are slogging through complex risk-benefit analyses of commercial products touting microbial benefits. And there is key work on improving soil, depleted or destroyed by millennia of agriculture, using microbial 鈥渋noculants鈥�.
We also have some 鈥渓ong-shot鈥� solutions for climate adaptation, especially when it comes to protecting coral reefs, Allison tells me later in an email. There are scary forecasts about losing most of the world鈥檚 coral reefs by the end of this century, so 鈥減robiotic鈥� microbes that boost heat tolerance and reduce bleaching could save reefs that millions depend on.
Overall, The Age of Microbes is a must-read as climate change bites deeper. Let鈥檚 hope that microbes do indeed prove to be an excellent addition to our armoury.
Three more great reads about biology鈥檚 frontiers
by Rob Dunn
Rob Dunn explores the biology of homes, from moths in cupboards to thousands of species of insects, bacteria, fungi and plants under our noses. Kill them in the name of 鈥渃leanliness鈥� at our peril.
by Michael Grunwald
We might be making things worse by following bad science (and politics) in the fight to feed (maybe) 10 billion people by 2050. Michael Grunwald offers an intriguing narrative.
by Karen G. Lloyd
For more great storytelling, check out microbial biogeochemist Karen Lloyd鈥檚 journey to Earth鈥檚 deep biosphere. Its 鈥渁lien鈥� life forms could make us rethink how life is supposed to work.
Christa Lest茅-Lasserre is a science journalist specialising in animal health and behaviour
When you make a purchase via聽the links on this page, we receive a commission.
