Strange fish: Lake Malawi is home to some unique species. Photo: Getty
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Genes are not as important as you might think

Michael Brooks’s Science Column. 

If you ever count the segments on a centipede, you’ll find there’s always an odd number of them. This isn’t because that’s what the genetic code of each species says must happen; it’s because the processes behind a centipede’s development constrain what is possible.

According to a growing number of researchers, the standard story of the influence of genes is overblown. So many other factors influence how we turn out as individuals and how we evolve as a species that the fundamentals of biology need a rewrite. “This is no storm in an academic tearoom,” a group of biologists wrote in the journal Nature in October. “It is a struggle for the very soul of the discipline.”

An organism’s environment is another complicating factor. Shape, for instance, is supposed to be genetically determined in fish. However, a trip to Lake Malawi has shown how shallow that idea can be. The lake’s cichlid fish are genetically unique, yet some species look a lot like those in the nearby Lake Tanganyika. Their big, pouting lips and protruding foreheads seem to be a result of environmental pressures and developmental pathways and not genetic instructions.

The shape of a sycamore leaf, too, is determined only in part by genetics. The chemistry of the soil the tree is growing in, even just its wetness, affects the outcome. And wetness matters to commodore butterflies: they emerge from the chrysalis orange in the dry season and blue in the rains.

So, life is complicated. Random mutations in DNA play a role but so do plenty of other factors. What’s fascinating is that even those random mutations are more complex than we thought: some may be driven by the most fundamental processes in the universe.

At the cutting edge of physics, researchers believe that quantum uncertainty, a kind of blur at the root of physical processes, brought the cosmos into being. Our advanced engineering tools exploit this uncertainty to make lasers, silicon chips and all the gadgets of the 21st century. And at the cutting edge of biology, the same phenomenon is being held partly responsible for driving evolutionary change.

That’s because some genetic mutations result from a seemingly innocuous misplacement of protons within the DNA molecule. Protons are one of the constituents of atomic nuclei and are able to exploit quantum phenomena such as uncertainty. They don’t have to be in just one place, for example; a single proton can exist in two different places on the molecule. Until, that is, the cell’s molecular machinery arrives to read the instructions encoded in the DNA. This action forces the proton into one place or the other, an action that will, in some outcomes, bring about mutations in the DNA’s structure.

The Surrey University geneticist Johnjoe McFadden was the first to suggest that biology may exploit this peculiarity of quantum physics. It may be, he says, one of many quantum tricks at work in the living world. He has outlined the possibilities in a new book, Life on the Edge, co-written with the theoretical physicist Jim al-Khalili. The pair believe that animal migrations, photosynthesis, the sense of smell and a slew of other everyday phenomena might be quantum at heart.

The idea of a quantum aspect to biology was first suggested by Erwin Schrödinger in his 1944 book What is Life? This inspired the physicist Francis Crick to move into biology and led to his 1953 discovery, with James Watson, of the structure of DNA. After that, few paid quantum biology much attention. However, with biologists facing uncertainty about what lies beneath their discipline, Schrödinger’s idea may be about to rise again. 

Michael Brooks holds a PhD in quantum physics. He writes a weekly science column for the New Statesman, and his most recent book is At the Edge of Uncertainty: 11 Discoveries Taking Science by Surprise.

This article first appeared in the 06 November 2014 issue of the New Statesman, Running out of Time

Photo: Getty
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Radio as shelter: Grenfell Tower was too frightening to look at

No song seemed to fit the mood on Hayes FM.

“Amidst all this horror, I hope to bring you some light relief. Here’s James Taylor.” Two days after the Grenfell Tower fire, a popular community station a little west of the incident was uncertain what note to strike.

The repeated ads for alarms detecting carbon-monoxide leaks (“this silent killer”) and tips on how to prevent house fires (“Don’t overwhelm your sockets and cause a spark”) sounded perhaps a little overassertive, but then the one for a day-long course focusing on resisting gender stereotyping (“Change the narrative”) felt somewhat out of place. And no song seemed to fit. James Taylor’s “Shower the People” turned out OK, but the Cranberries’ “The Icicle Melts” was unceremoniously faded out mid-flow.

This does often happen on Hayes FM, though. There are times when the playlist is patently restless, embodying that hopeless sensation when you can’t settle and are going through tracks like an unplugged bath – Kate Bush too cringey, T-Rex too camp – everything reminding you of some terrible holiday a couple of years ago. Instead, more ads. Watch your salt intake. Giving up smoking might be a good idea. Further fire safety. (“Attach too many appliances and it could cause an overload and that could cause a fire. Fire kills.”)

Then a weather report during which nobody could quite bring themselves to state the obvious: that the sky was glorious. A bell of blue glass. The morning of the fire – the building still ablaze – I had found three 15-year-old boys, pupils at a Latimer Road school that stayed closed that day because of the chaos, sitting in their uniforms on a bench on the mooring where I live, along the towpath from the tower.

They were listening to the perpetual soft jangle of talk radio as it reported on the situation. “Why the radio?” I asked them, the sight of young people not focused on visuals clearly unusual. “It’s too frightening to look at!” they reasoned.

Radio as shelter. As they listened, one of them turned over in his hand a fragment of the tower’s cladding that he must have picked up in the street on the way over – a sticky-charcoaled hack of sponge, which clung like an insect to his fingers whenever he tried to drop it. 

Antonia Quirke is an author and journalist. She is a presenter on The Film Programme and Pick of the Week (Radio 4) and Film 2015 and The One Show (BBC 1). She writes a column on radio for the New Statesman.

This article first appeared in the 22 June 2017 issue of the New Statesman, The zombie PM

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