What is everyone talking about this week: The secret life of plankton
Plankton generates at least five times more oxygen than tropical rainforests. Yet its various subspecies remain opaque and poorly understood. That could soon be changing.
As the Season gets under way this month, Britain’s intelligentsia will descend upon the Hay Festival. I’ve always loved that a glorified book fair on the Welsh borders can morph into our very own Venice Biennale: a who’s who of Life & Arts where Dua Lipa might clink glasses with the Pope. It all began in 1988 with the winnings from a game of Poker; a year later, the festival was welcoming Arthur Miller as a headline act.
Hay has helped to shape the cultural discourse ever since, a cursory glance at its keynote speakers in the intervening decades akin to looking through a time capsule. The gradual addition of certain names and roles within Hay’s governing body reveals the varying concerns of the age: inequality, free speech and artificial intelligence. To Hay’s credit, these concerns tend to stick. No doubt the most recurring, however, is the climate.
This year is no different, although the focus will shift from the more usual suspects (birds, weather and renewable energy) to something more conspicuously bland: plankton. As ever, Hay is on the money. What for years have been mumblings about the ripple-effect of aquatic plants, on everything from global warming to biodiversity, are finally getting their dues. Leading the charge is Vincent Doumeizel, a senior adviser on oceans to the UN Global Compact, whose talk at Hay on May 23 has already sold out. His new book, The Power of Plankton (The Book Social, £19.99), identifies this as the source of all life.
Plankton makes up 90% of the biomass in our oceans. Its myriad subspecies live in suspension, perpetually drifting, unable to work against the current. This impotence is misleading: plankton defines the temperature of the planet, absorbing roughly half our global emissions and converting carbon through photosynthesis. It helps to form clouds — which, in turn, reflect the sunlight — and, where oxygen production is concerned, it outperforms rainforests by as much as 400%.
The trouble is we know little about how it actually works, its species’ microscopic size and geographical spread working against researchers. What we do know tends to raise only more questions: why are there so many subspecies and why does this not beget more competition? Why do some resemble algae, but others look closer to shrimp? A mystery we have solved is this: plankton’s role as a sequester of carbon is effective only when it sinks. The key subspecies here are grouped under the name of diatoms, the number of which is falling in open-ocean regions. That of surface plankton, by contrast, is rising.
Other regions, ruled by different currents, tell yet another story. Perhaps theirs is more positive; although, without further research, conclusions will remain uncertain. ‘If we understand plankton,’ Mr Doumeizel said two weeks ago on the Futureproof podcast, ‘then we begin to understand the biology of our oceans.’ Learning — and funding —starts with conversation. Let us hope this one doesn’t crash too soon after takeoff.
This feature originally appeared in the May 13, 2026, issue of Country Life. Click here for more information on how to subscribe.
