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In praise of slime moulds

July 2, 2015

This spring was a wet one where I live. If the same goes for you, perhaps you’ve noticed a sprinkling of unsightly splodges coating leaves and stems in your flower bed or lawn. This is a slime mold, an ancient single-celled amoeba, similar to a fungus (using spores to reproduce), which lives in soils from Antarctica to the Arctic. For most of its life cycle, mold leads an unexceptional life, but sometimes it bands together in communities of thousands to form large shapeless blobs known as a plasmodium—an organism in its own right, encased in slime. It’s harmless and easily washed off with a hose, but before you exterminate this most primitive of life forms, consider how extraordinary it is.

An individual slime mold lives quietly, but once part of the blob, it is capable of incredible maneuvers and exploits. It can creep, crawl, pulsate, grow tentacles, and even negotiate a maze, seducing a substantial fan base of biologists eager to tinker with this most mundane research subjects. Their favorite is Physarum polycephalum, a yellow slime mold that conducts electricity. Scientists have wired it to a silicon-based circuit to create an interactive biocomputer, allowing technologists to get in on the act: Professor Eduardo Miranda, of Plymouth University in the United Kingdom, has performed a piano duet with a slime mold. Others have used the mold’s extraordinary ability to negotiate the shortest routes to map the Roman roads of ancient Britain.

The more we learn about the extraordinary skills of this most ordinary group of cells, the greater the parallels I see in our human communities. Individually, we may seem powerless to affect much beyond our immediate lives, but as a species—as humanity—we are altering the planet with unprecedented power. Humanity is changing the climate, the biodiversity of life, the chemistry of the atmosphere and oceans, global landscapes, and so much more. Like the blob, we are an extraordinary force. The challenge is to ensure that as individuals we are not as inconsequential as the amoeba in directing our powerful blob.

This column originally appeared at The American Scholar.

The big one

June 23, 2015

When I was in elementary school, my geography teacher showed the class a black and white photograph of San Francisco in flames. It was taken in 1906 after a violent earthquake, we were told. And thus began our lesson on earthquakes and the dangers thereof. As we sat there listening to tales of deaths and other horrors that befell the city, Miss Jenkins assured us that such a quake will certainly happen again. So why, I wondered, do people continue to live in San Francisco?

People’s perception of risk is only partly based on the statistical likelihood of an event occurring. A landmark 1989 review of risk by Paul Slovic concluded that people are much more worried about uncontrollable catastrophic events, such as a nuclear war, than statistically more likely ones, such as a vehicle accident. Perhaps because of this, the state has had to intervene to protect us from our own risky behaviors—think seatbelt laws and antismoking regulations.

But our failure to respect the earth’s power to obliterate us, by building homes in at-risk areas, seems to contradict Slovic’s conclusion. In some places, people seek out dangerous flood zones because they have more fertile soils to farm or a pleasant riverfront location; others risk dangerous avalanches because of the fun and challenge of climbing mountains; still others choose to live in San Francisco because it’s a pretty and dynamic city. The U.S. Geological Survey recently raised the likelihood of San Francisco experiencing the “Big One”—an earthquake of magnitude 8 or more—in the next 30 years. Quite something to consider if you’re taking out a mortgage there.

By continuing to build and live in known risk zones, we effectively turn a natural disaster into a manmade one. Human effects, such as climate change, deforestation, rerouting of rivers, or other land-use changes amplify the risks of natural events. But if anything, we appear to be more blinkered than we would expect to these manmade risks.

Most people have, owing to birth or circumstance, no choice about living in a risky place. They are the unfortunate victims of quakes (such as the one that hit Nepal in April), volcanic eruptions, tsunamis, deadly disease, and so on.

We can reduce these risks. Buildings in quake zones, such as San Francisco and Tokyo, have to comply with safety regulations—the equivalent of a seatbelt. But what about those in poor countries? When disaster strikes, the losses are more often economic for rich countries and mortal for poor ones.

And because many of our manmade risk amplifiers, such as climate change, now have global effects, surely it’s time we made our seatbelt regulations global too.

This column first appeared at The American Scholar.

Breezing up a fair wind

June 16, 2015

Of all the forces of nature, I should think the wind contains the largest amount of motive power—that is, power to move things. And yet it has not, so far in the world’s history, become proportionably valuable as a motive power. It is applied extensively, and advantageously, to sail-vessels … a few windmills, and pumps. … Quite possibly one of the greatest discoveries hereafter to be made, will be the taming and harnessing of [wind].

Thus declared Abraham Lincoln in an 1860 lecture.

Lincoln would surely be delighted at the new fashion for windmills, the off-shore plantations sprouting across the globe and the more contentious ones decorating farmland like candles on a birthday cake. Although we can now generate electricity from wind efficiently, little has changed in the past 150 years, and wind power is still not as valued as, say, oil, coal, or gas. Meanwhile, the world has warmed and become far more polluted since 1860. It is high time we switched our power source from filthy fossil fuels to wind, solar, and other clean “forces of nature.”

We have still not solved that fundamental problem of taming and harnessing the wind. Fossil fuels come in highly concentrated, tangible, transportable packages that can be burned to release energy anywhere, day or night. But the wind doesn’t always blow (and never with a constant force), the sun is regularly fickle, and water vanishes in the heat.

The solution is to turn the motive power of wind into a chemical fuel—like the handy fossil-fuel packages—by using wind to charge up a battery, which could be used wherever and whenever it’s needed. But so far, the inability of battery technology to store electricity effectively has frustrated our efforts toward adopting clean power.

A recent trickle of innovations in cheaper, lighter, more efficient batteries suggests that this may be about to change. As with the 19th-century oil rush, there is a lot to play for. For example, the entire nation of Bolivia, home to most of the world’s lithium deposits, is staking its hopes on an efficient lithium-based battery.

Indeed, until recently, lithium was the frontrunner, already used in phones, laptops, electric cars, and wind turbines. But in April, scientists announced the development of an aluminium-based battery that can charge a smartphone in just one minute, is safer (lithium batteries have an unfortunate tendency to explode), more reliable and durable, cheaper, and is flexible enough to be bent into different shapes. The voltage of aluminium batteries will need to improve to match lithium, but bad news for Bolivia promises good news globally.

Aluminum batteries could be used to power vehicles, homes, and offices, and arrays of them could even power towns. The age of wind power may finally be arriving.

This column first appeared at The American Scholar.

Unnatural beings

June 13, 2015

Artificial intelligence is big on the big screen this year, from the sexy female robots of Ex Machina to the superheroes in the Avengers: Age of Ultron. Hollywood often reflects real-world technological advances, such as those in the field of robotics: last year, a chatbot called Eugene Goostman became the first computer to pass the Turing test—based on Alan Turing’s famous poser: “Can machines think?”—in which a computer must convince a human more than 30 percent of the time that it too is human. Eugene Goostman managed this for 33 percent of the time, although there is disagreement over how valid the test was. Some believe that computers will take over the human world—they are already replacing humans in the workplace, from factory floors to complex monitoring of hospital patients, and our dependence on smartphones and data systems suggests they already have taken over.

But as machines become more humanlike, aren’t we humans meeting them halfway? Are computers not simply an extension of our brains? Our inventions may better resemble humans, but we are becoming more machine-like in the process. Are we no longer a natural species, or are we simply a part of nature that has evolved to become less “natural”?

We have shifted our evolutionary pathway with medical advances to save those who would naturally die in infancy. We have surmounted the limitations that restrict other species by creating artificial environments and external sources of energy. A 72-year-old man now has the same chance of dying as a 30-year-old caveman. We are supernatural: we can fly without wings and dive without gills, we can grow new body parts from cells or build mechanical replacements, we can survive killer diseases and be resuscitated after death, we can communicate with people thousands of miles away, control the biodiversity of life, the direction a river flows, even the temperature of the atmosphere—and all this after being conceived in glass.

Rather than fearing a sci-fi scenario where robots take over the world, we should perhaps be looking more closely at the way our newly powerful species is taking over nature. And asking: Can unnatural humans think intelligently?

This column first appeared at The American Scholar.

New column

June 4, 2015

I’ve started writing a weekly column about interesting science/nature stuff, called World of Wonders, for The American Scholar. The first one is here.

And my book has had a lovely review in The Ecologist magazine, where Robert Hunziker describes it as “a masterpiece”!

This Saturday 6 June, I’m interviewed on Science Radio with Dr Atala, at noon ET on Sirius XM Insight (Channel 121) – you can sign up to a fee trial here.

I’ve been a bit preoccupied with home-life recently – I have a new spring baby – but I’m getting back to writing… You can read my latest feature on the fascinating vagus nerve here. And I’ll try to post more regularly here!

What is the extreme present?

May 26, 2015

I’ll be in conversation with people who may know at Southbank Centre on Saturday evening. Come and join us!

Review in Science

March 6, 2015

My book has received a nice review in Science magazine by University of California Santa Barbara ecologist Hillary Young.


Adventures In The Anthropocene: A journey to the heart of the planet we made is currently discounted on Amazon!



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