Tiny Startup Completely Reinvents How We Use Touchscreens

If you want a reminder of how far technology has come in the last decade, check out the YouTube clip of Steve Jobs unveiling the first iPhone to a room full of people back in January 2007. In it, Jobs teaches his audience, step by step, how to swipe and scroll through photos. He shows them how to rotate the device so that they can see an image in landscape. And he demonstrates what he calls “the pinch,” pressing his fingers together and moving them farther apart to zoom in on an image. After the pinch, the crowd lets out a collective “Whoa.”

Yes, in hindsight, it’s kind of adorable. But what’s important to note about the moment is that when Jobs revealed the iPhone to the crowd, he was not only introducing the audience to a new device. He was teaching them a new language, a new way of interacting with a computer.

THIS TINY STARTUP HAS DEVELOPED A NEW TECHNOLOGY THAT CAN DETECT THE DIFFERENCE BETWEEN A FINGERTIP, A KNUCKLE, A FINGERNAIL, AND A STYLUS.

Now, seven years later, Qeexo is hoping to emulate Steve Jobs. Backed by $2.3 million, the San Jose, California-based startup has developed a new touchscreen technology that can detect the difference between a fingertip, a knuckle, a fingernail, and a stylus. By assigning different parts of the finger to different actions, this technology–known as FingerSense–could reduce tasks that currently require multiple steps to just one. “You can imagine it’d be like having different buttons in your hand,” explain’s Sang Won Lee, the company’s co-founder and CEO.

The iPhone, and indeed the entire smartphone industry, have evolved dramatically since that day in 2007. And yet, for all the features that have been tweaked and perfected over the years, the language Jobs taught us has remained unchanged. We still use a single input–a fingertip–to operate the device. And that limits the way we use our phones. On a desktop, there’s a mouse, a right click button, a shift button, and many other inputs that serve different functions. But on the smartphone, because there’s just the fingertip, a common task like copying and pasting becomes a tedious process of tapping, holding, dragging, and selecting. Qeexo wants to finally put the smartphone on par with the desktop.

Image: Courtesy of Qeexo

Good Vibrations

The technology was first invented by Chris Harrison and Julia Schwarz, the two other Qeexo co-founders, who were pursuing their Ph.Ds at the Human-Computer Interaction Institute at Carnegie Mellon. They, like many in their field, were trying to come up with a solution to this “multi-touch” problem when they began experimenting with ways to identify objects by their different vibration patterns.

At the time, Lee was working for electronics maker HTC, scouting new user experience technology for smartphones. Having worked in the product planning industry since 2003 when he got his start at Samsung, Lee was familiar with the industry’s desire to come up with a new way for people to interact with their screens. Then, in 2012, he found Harrison’s blog post about the prototype he and Schwarz had developed. “I thought this could really solve that problem the industry was having,” Lee says. So he left HTC, and in September of that year, the three co-founders launched Qeexo.

FINGERSENSE USES THE STANDARD ACCELEROMETER IN A MOBILE DEVICE TO PICK UP ON THE VIBRATION PATTERNS DIFFERENT PARTS OF THE HAND PRODUCE.

Today, FingerSense uses the standard accelerometer in a mobile device to pick up on the vibration patterns different parts of the hand produce when they come in contact with a touchscreen. The FingerSense machine-learning engine understands what part of the finger is touching the screen and triggers a correlated action. For instance, tapping a block of text with your knuckle could trigger the copy and paste menu to appear. To select text, you’d simply drag your knuckle down the text, much like you would a desktop mouse.

Lee says this technology could have implications beyond the world of smartphones and tablets. Touchscreens in cars could be greatly improved, for instance, if drivers could simply knock on a screen with their knuckles instead of taking their eyes off the road to press multiple buttons in a row. But what might really make Qeexo one of those rare technologies that can make a room full of people say “Whoa” is that touchscreens are just a start. The company is also working on products like FingerSense on Walls, which would allow you to set your device on a table and control it by tapping on the table. FingerSense on Body, another product that’s in its conceptual phase, would make it easier to control wearable devices with tiny screens, because it would enable people to tap on their arm or hand instead.

Lee says much more work needs to be done to develop sensors sensitive enough to pick up on vibrations through something like skin. Still, according to Mark Rolston, the former chief creative officer of frog design and founder of the user experience design firm argodesign, the progress Qeexo has made on smartphones alone is a major accomplishment. For years, he says, people within the industry have been researching new input methods, but few have found a way to actually tie those new inputs (the knuckle, in our example) to specific functions (text selection). “It’s not necessarily intuitive,” he says of FingerSense, “but neither were right click or the shift button, and those things have been adopted, and they help us. Something like this is one of the better ideas to come along.”

‘Dangerous Territory’

That doesn’t mean it won’t be without its obstacles. Rolston says Qeexo is entering into “dangerous territory,” because now, it has to convince all the major device manufacturers, from Apple to Samsung, to adopt its technology at once. Not only that, Qeexo also has to convince these ruthless competitors to come to an agreement as to how the technology should be used. A knuckle tap, in other words, can’t perform a different function on a Samsung phone and than it does on an iPhone.

“It’s all or nothing with methods like this. They’re useful when everyone expects them to be around, and therefore, application developers adopt it,” Rolston says. “So we can love it, but it’s really adoption that matters.”

And then, of course, there’s an even bigger risk, and that is the fact that these device manufacturers, with their swollen patent portfolios, could develop their own version of FingerSense themselves. Lee, for one, does not underestimate his competition. “Whoever wants to grab this market and become the next generation de facto standard is going to be our competitor and become one of the challenges we need to overcome.”

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The Physics of Keeping Cool

Refrigeration: the process of decreasing the temperature of some thing (my definition). Air conditioning (AC) can be a form of refrigeration.

There are several ways to reduce the temperature of things – like a person or a beer. The history and physics of cooling things can be quite interesting. I’m not a historian, so I am only going to speculate on the timeline of events in the life of refrigeration. However, I feel comfortable explaining the physics in each method.

Humans Discover Sweat

Humans just can’t help it. Sometimes they get hot. But alas! Humans have a built in cooling systems. It’s called sweat. In order to understand how it works, maybe we should first look at temperature. You can measure the temperature in Celsius (°C) or Fahrenheit (°F), but what are you actually measuring?

If I were to give a simple definition of temperature, I would say that it is a measure of the average motion energy of the particles that make up that object. That’s not a perfect definition, but I think it will be fine for now. This means that when you cool something, you decrease the average motion energy (kinetic energy) of its particles.

How does sweat cool you off? It works through the evaporation of water. Let me explain. Suppose we have some water at room temperature (about 23°C). This means that the water molecules in this group of water has an average kinetic energy of some value (it doesn’t matter how much). But not all water molecules are the same. Instead there is a distribution of kinetic energies. Some molecules are moving quite slow and some are moving very fast. It’s possible that these very fast (and few) molecules can escape the liquid water and become gas water (we call it water vapor). What’s left is a water but now with a lower average kinetic energy since the highest KE molecules just left. Here is an older much more detailed post about evaporation.

If this water is a bead of sweat on the skin of a human, the water can be colder than the skin and cool it off through conduction (which I will talk about next).

I Photo

This sweaty boy is hot and sweaty after soccer practice. Image: Rhett Allain

Oh, important thing to notice. If your body sweat is working correctly, all of this water-sweat your body produces will evaporate and you will be dry (but still stinky). In very humid regions, the sweat-water doesn’t completely evaporate and you are still stinky.

Cooling by evaporation isn’t just for living things. You can actually use something like this to cool off something in your house. Here is a video I made showing this effect with a wet cloth and water bottle. Oh, you can even use hot water on the wet cloth and it will still cool down the water bottle (or beer).

Really, you should try that experiment at home. It’s awesome.

Humans Learn to Store Ice

It doesn’t take a genius to realize that in the winter, there is ice on the lakes but not in the summer (unless you are in that movie my kids love – Frozen). What if we just take that ice and store it somewhere so it doesn’t melt so fast? Then, in the summer we can bring out out to make lemonade?

That’s pretty much exactly what happened.

I Photo

Water is something else you can get cold, but it’s not as good as beer.Image: Rhett Allain

How does ice cool things down? This is called heat conduction. The basic idea is that when two objects are in contact, there will be a transfer of energy from the hotter object to the cooler object until the two reach the same temperature. This leads me to my favorite definition of temperature.

TEMPERATURE IS THE QUANTITY THAT IS THE SAME FOR TWO OBJECTS IN CONTACT FOR A LONG TIME.

That definition seems so obscure, but it’s actually a fine way to put it.

Back to ice. Ice doesn’t just cool by contact. Well, it does until it reaches it’s melting point at 0°C (32°F). In order for the water to make a phase transition from solid to liquid, it requires even more energy. Where does this energy come from? Yup. It comes from the surroundings.

Humans Create the Kegerator

What exactly is a kegerator? This is JUST like a refrigerator except you put a keg of beer in there. Oh, and you add a tap on the top or door so you can get cold beer without even opening the fridge door. Awesome, isn’t it? You might think I’m kidding about the kegerator, but I’m not. Keeping drinks (and beer) cold was a consideration for both cooling by ice and refrigerators.

But how does a refrigerator work? It’s all about compressing a gas and letting it turn into a liquid and then evaporate back into a gas. That might seem crazy, but here a demo you can do on your own to get an idea of how this would cool. All you need is a rubber band.

Take the rubber band and touch it to your lips to get a feeling of the temperature of the band (lips are more sensitive than your fingers). Now stretch the rubber band as far as you can without breaking it and touch it to your lips again (quickly). You should be able to feel the rubber band is now hotter than it was. Next, just hold it in a stretched position for a short time so that it can cool off to room temperature. Finally, let the rubber band compress back to its original size and feel it again. Guess what? It’s cooler than room temperature. Here’s the same thing in a video.

Your AC and refrigerator don’t use rubber bands. Instead, there is a gas (called a refrigerant). This gas is compressed and gets hot in the process. If you have ever pumped up a bike tire, you might have noticed that the tire gets hot – same idea here. Since this hot compressed gas is hotter than the surrounding air, it transfers (through conduction) energy to the air and decreases it’s temperature. This also causes the gas to condense into a liquid.

The next step is to take this liquid and allow it to expand into a gas. This phase transition and expansion into a gas takes energy. Of course the energy comes from the surroundings. This is the cooling part of the AC or refrigerator. The gas then goes back into the compressor and the cycle continues. Yes, I missed some details but that’s the basic idea.

I Photo

The inside of a freezer can get quite cold. Image: Rhett Allain

I didn’t say anything about geothermal cooling. This basically just cooling by conduction expect that you want to make thermal contact with things underground. At some times, the ground temperature is colder than the air temperature and can be used to cool things off. Yes, there are also some other cooling methods. Maybe in the future we will have magnetic based refrigerators.

One final thought: Why is it so much easier to increase the temperature of something than it is to decrease the temperature?  Maybe this will be a future blog post.

How Evolution Works, Animated in Minimalist Motion Graphics

From Darwin to your dog, or why DNA copying errors explain blue eyes.

“Creationism is a small, dogmatic minority, legendary science writer and evolution-illuminator Stephen Jay Gould proclaimed, “and they make more noise than their numbers.” But despite Gould’s confident optimism, we live in an age when creationism is still taught in classrooms and mythology requires constant debunking with reality in order to keep the voice of reason from being drowned by that noise. Sometimes, however, it’s simply a matter of conveying the science of evolution with equal parts captivation and clarity.

Since the days of Darwin, the theory of evolution has lent itself to ample visualization, animation, and even rap. This lovely motion graphics piece combines animation and infographics to explain the complexity of evolution with delightful simplicity.

Complement with this graphic biography of Darwin, Neil deGrasse Tyson onwhy intelligent design is a philosophy of ignorance, and the visual history of evolution.

The Man Who Speaks For Earth

Recently, at a mass in Vatican City, Pope Francis said that, if given the chance, he would baptize aliens. (“Who are we to close doors?” he asked.) Unfortunately, judging by “Archaeology, Anthropology, and Interstellar Communication,” a new book, about the complexities of communicating with extraterrestrials, released last month by NASA, it won’t be that simple. For a long time, the people most interested in searching for extraterrestrial intelligence came from “hard science” disciplines like astronomy or physics; to them, the main obstacles seemed technical (building radio telescopes, processing signal data). But, in recent years, the field has broadened to include people who already study other civilizations here on Earth. In these essays, they report that their jobs are hard enough as it is. Archaeologists struggled to decipher ancient Greek; deciphering a transmission from another world will be even more difficult. Even if we do manage to detect a signal, they write, fully understanding what it means may be impossible.

The challenges described by the contributors are daunting (and, at least to me, surprising). On Earth, they write, we were able to use the Rosetta Stone to figure out Egyptian hieroglyphics. (It contained the same text written in glyphs, Demotic script, and ancient Greek.) But there will be no Rosetta Stone for our communication with extraterrestrials, and the distances involved make conversation unlikely—which may mean that our comprehension of their message will be confined to math and numbers, never able to make the jump to broader concepts or less abstract words. (How do you describe a lake, or a tree, with math?) The speed of the message presents another problem: here on Earth, human language happens at a speed somewhere between birdsong and whalesong, so how fast should our message be, and on what scale should we be listening? And then there are all the difficulties created by the nature of our interlocutors. What if they’re so different from us that our messages are mutually incomprehensible? What if the message is sent by some sort of automated system—a voicemail from a long-dead civilization?

Douglas Vakoch, the editor of “Archaeology, Anthropology, and Interstellar Communication,” is the director of interstellar message composition at the SETI Institute, in Mountain View, California. (The Institute’s name refers to the “search for extraterrestrial intelligence,” an umbrella term for a number of projects that began in the sixties, some funded by NASA.) Vakoch has degrees in comparative religion, the history and philosophy of science, and clinical psychology (“I expected to become an astronomer, but discovered that I was more interested in people than in stars,” he told me). At SETI, Vakoch is responsible for designing the messages that we might send to extraterrestrials; he is also a member of the International Institute of Space Law, where he works on the policy issues surrounding the messages’ composition. (There are currently no laws about sending signals into space; in theory, anyone with a powerful enough antenna could be talking to the cosmos right now.) “We used to think we would get an Encyclopedia Galactica,” Vakoch said. One of his primary goals, in editing the book, was to give air time to the less optimistic views of social scientists, and to start thinking about what an incomplete or indecipherable message from space might mean to humankind.

Vakoch spoke to me by phone, from his home in California. This interview has been edited and condensed.

TheNewYorker

“Stargate” notwithstanding, when I think of space, archaeologists and anthropologists don’t come to mind. What do they contribute to the SETI effort?

Anthropologists are very familiar with encountering those who are radically other; archaeologists are very good at saying, We have only a fragment of a past civilization, and we’re trying to reconstruct it. Both of those situations will be at the center of communicating with extraterrestrials. When we take seriously the distance between us and any other civilization, we see that we have no easy way to ask a question and get a reply. We don’t even know what language they’re going to be using.

And if we’re thinking of replying, and of getting a reply back, then we have to ask: How do we make sure that, one thousand years from now, future humans will be able to understand that message? Because it’s only at those time scales that it becomes plausible that we’ll begin to understand something.

Your job is to help design the messages we might send to extraterrestrials. What’s the starting point for that work? How do you begin?

There is no obvious starting point, but there are some approaches that are easier than others—for example, mathematics. So then the question is, What are the most fundamental parts of mathematics? Maybe it’s counting. Maybe mathematics as a whole isn’t universal, but if we can start with something fundamental, we can build up to communicating, step by step, our way of bringing order into the universe.

It’s also useful to step back and look at communication more generally. In the early days of SETI there was this idea of “send them information, and make it redundant, and the patterns will be self-evident.” Nowadays, that seems ridiculous. So what’s the alternative? If something like language—whether a natural language like English or Mandarin, or a language like mathematics—if those aren’t universal, maybe we can step back and look at signs in a more general sense. That’s one of the ways in which semiotics has been helpful. Maybe a big accomplishment in communicating with an extraterrestrial is just to convey that there’s something on this end who’s intending to send something. Even if it’s something as rudimentary as sending an index—a message that points toward an astronomical object—or an icon, something that looks like, say, the radiation pattern of hydrogen. Just so they say, “Oh, these are sign-bearing, sign-using creatures—there’s hope.”

Has SETI, or has anyone, actively started broadcasting in a way designed to attract notice?

There have been a few transmissions. There hasn’t been anything sustained, though, and I think there would be real advantages to starting a sustained transmission. That would increase the sense of this being an intergenerational project. It signals our own hopes for humanity—that we hope to be around in one thousand years to get a reply back. We recognize that what we do today is just one step in contact.

One of the most inhibiting aspects of interstellar communications is the sense that, somehow, we need to get everything absolutely right and completely comprehensible the first time out. That’s not how we communicate on Earth.

You’re in favor of transmitting sooner rather than later?

If it turns out that we actually have little hope of understanding a message, how does that affect our search strategies? Maybe it makes sense for us to start transmitting. The way it’s typically been cast in the past is, They’re smarter, and they’ll be better at sending an intelligible message. But the flip side is, if they’re smart, they’ll also be better at decoding an ambiguous message. Maybe they’ll be able to detect, from the form of the message, “This seems to be something we’ve seen from visually oriented species, or auditory-oriented species.” That might be more important.

Let’s suppose that at some point we do make contact, but using these ambiguous, perhaps indecipherable messages. What’s the point of that?

First of all, we have to think, For whose benefit are we sending this message? Is it for our benefit, to say that we existed? To say, Here are values that we have? You could also ask, What would an extraterrestrial want to know? We could say, “We’re wise, we’re strong.” A more interesting message might be, “This is what we’re struggling with; we don’t know if we’re going to exist for another century, or what life will look like on this world then.”

One of the benefits of all this is, we have to reflect on what we want to say, and how we want to say it. We have a Web site called Earth Speaks, where we ask visitors to contribute what they would like to say to an extraterrestrial. We look at the words people use: in comparison to English in general, the world “but” is used one hundred and fifty times more often.

On the other side: in the book, [the philosopher and cognitive scientist] Dominique Lestel talks about the implications of realizing, over the course of millennia, that we really can’t communicate or decipher a message. And he calls it an existential crisis. Because how does that impact our understanding of what we’re doing when we’re doing math, science, philosophy?

It seems like the trend has been toward a more pessimistic outlook, at least as far as interpreting a message is concerned. Are there any optimistic trends?

What you describe as pessimism I would characterize as skeptical and critical. But it’s a criticism that engages, as opposed to a criticism that dismisses. We’re getting closer to understanding, What are the complexities we face? And what are their implications?

One of the big positive developments is that, in the last fifteen years, we’ve learned that there are planets out there. Now we know that almost every star has planets—about one out of five probably has an Earth-like planet in a habitable zone. Knowing where the planets are lets us prioritize those targets in our searches. This actually would have been even more relevant if it had turned out that planets are rare! But the very fact that we’re finding so many—we now know there are roughly Earth-sized planets within the habitable zones of even red dwarfs—that’s a game changer. We know there are places where extraterrestrials could live.

And what if you work at SETI for the rest of your life, doing this work, and you don’t find anything?

There are payoffs to the project that we can be assured are happening, at some level, with some degree of depth. But the greatest outcome—actually making contact with and understanding another civilization—that’s difficult to have any assurance of. So this is a case where the project requires an ability to stand in the unknown. Science is usually associated with values like objectivity and truth, and we want those, too. But one of the values behind SETI is patience.

Illustration by Dadu Shin.

France training rocked by spying claims

France manager Didier Deschamps has reportedly called for an investigation after a drone hovered over their training session.

There are suggestions a drone – a small unmanned flying machine generally used to spy on military targets – flew over the training camp in Ribeirao Preto yesterday.

News agency Ansa claims many of the players joked about the drone, but that coach Deschamps and his staff were less amused by the incident.

They fear one of their opponents in the World Cup, or even the French media, are attempting to spy on closed training sessions.

France are in Group E with Switzerland, Ecuador and Honduras.

Football Italia

Forget the Turing Test: Here’s How We Could Actually Measure AI

A chatbot pretending to be a 13-year-old Ukrainian boy made waves last weekend when its programmers announced that it had passed the Turing test. But the judges of this test were apparently easily fooled, because any cursory exchange with ‘Eugene Goosterman’ reveals the machine inside the ghost. Maybe the time has come, 60 years after Alan Turing’s death, to discard the idea that imitating human conversation is a good test of artificial intelligence.Screen Shot 2014-06-12 at 9.05.28 AM

“I start my Cognitive Science class with a slide titled ‘Artificial Stupidity,’” said Noah Goodman, director of the computation and cognition lab at Stanford University. “People have made progress on the Turing test by making chatbots quirkier and stupider.” Non-sequiturs, spelling errors, and humor all make a chatbot seem more human. The history of the Loebner prize, an annual Turing test competition, confirms this trend. Last year’s contest was won by a bot named Mitsuku also pretending to be young ESL speaker, a silly Japanese girl.

Even Turing anticipated thttps://thefeeed.wordpress.com/wp-admin/post-new.php#hat evasion might be the most human answer to a hard question:

Q: PLEASE WRITE ME A SONNET ON THE SUBJECT OF THE FORTH BRIDGE.

A : COUNT ME OUT ON THIS ONE. I NEVER COULD WRITE POETRY.

Because humans interact with the world through sight and sound, not strings of letters, a stronger test of human-like intelligence might include speech and image processing. Computer speech and text recognition has improved rapidly in the last twenty years, but are still far from perfect. When asked a question about the Turing test, Apple’s Siri answered about a “touring” test. Bots struggle to decipher squiggly letters, which is why you have to fill out a CAPTCHA(Completely Automated Public Turing test to tell Computers and Humans Apart) when you sign up for things like Facebook.

Because humans interact with the world through sight and sound, not strings of letters, a stronger test of human-like intelligence might include speech and image processing. Computer speech and text recognition has improved rapidly in the last twenty years, but are still far from perfect. When asked a question about the Turing test, Apple’s Siri answered about a “touring” test. Bots struggle to decipher squiggly letters, which is why you have to fill out a CAPTCHA(Completely Automated Public Turing test to tell Computers and Humans Apart) when you sign up for things like Facebook.

After all, UPS already routes millions of packages a day, hospitals sequence patients’ DNA to find cancer-causing mutations, and Google can in a millisecond report the age at which children begin to recognize their mother. These abilities are ”fricking fantastic, and way beyond the capability of a person,” said Goodman, the computation and cognitive science researcher at Stanford. “So in some sense the programs are super intelligent, super human, but because of our common-sense notion, we say that’s not intelligence, that’s something else.” As functions proliferate, some may become united behind a more flexible user interface and be powered by a deeper corpus. There might be a machine that can teach you a dance that it learned by watching YouTube and diagnose a disease by smelling your breath. You could ask that machine to simulate human behaviors in order to pass the old Turing test, but that would be insulting to everyone’s intelligence.

 

Why haven’t we encountered aliens yet? The answer could be climate change

Enrico Fermi, when asked about intelligent life on other planets, famously replied, “Where are they?” Any civilisation advanced enough to undertake interstellar travel would, he argued, in a brief period of cosmic time, populate its entire galaxy. Yet, we haven’t made any contact with such life. This has become the famous “Fermi Paradox”.

Various explanations for why we don’t see aliens have been proposed – perhaps interstellar travel is impossible or maybe civilisations are always self-destructive. But with every new discovery of a potentially habitable planet, the Fermi Paradox becomes increasingly mysterious. There could be hundreds of millions of potentially habitable worlds in the Milky Way alone.

This impression is only reinforced by the recent discovery of a “Mega-Earth”, a rocky planet 17 times more massive than the Earth but with only a thin atmosphere. Previously, it was thought that worlds this large would hold onto an atmosphere so thick that their surfaces would experience uninhabitable temperatures and pressures. But if this isn’t true, there is a whole new category of potentially habitable real estate in the cosmos.

Finding ET

So why don’t we see advanced civilisations swarming across the universe? One problem may be climate change. It is not that advanced civilisations always destroy themselves by over-heating their biospheres (although that is a possibility). Instead, because stars become brighter as they age, most planets with an initially life-friendly climate will become uninhabitably hot long before intelligent life emerges.

The Earth has had 4 billion years of good weather despite our sun burning a lot more fuel than when Earth was formed. We can estimate the amount of warming this should have produced thanks to the scientific effort to predict the consequences of man-made greenhouse-gas emissions.

These models predict that our planet should warm by a few degrees centigrade for each percentage increase in heating at Earth’s surface. This is roughly the increased heating produced by carbon dioxide at the levels expected for the end of the 21st century. (Incidentally, that is where the IPCCprediction of global warming of around 3°C centigrade comes from.)

Over the past half-billion years, a time period for which we have reasonable records of Earth’s climate, the sun’s surface temperature increased by 4% and terrestrial temperatures should have risen by roughly 10°C. But the geological record shows that, if anything, on average temperatures fell.

Simple extrapolations show that over the whole history of life, temperatures should have risen by almost 100°C. If that were true, early life must have emerged upon a completely frozen planet. Yet, the young Earth had liquid water on its surface. So what’s going on?

Get lucky

The answer is that it us not just the sun that has changed. The Earth also evolved, with the appearance of land plants around 400m years ago changing atmospheric composition and the amount of heat Earth reflects back into space. There has also been geological change with the continental area steadily growing through time as volcanic activity added to the land-mass and this, too, had an effect on the atmosphere and Earth’s reflectivity.

Remarkably, biological and geological evolution have generally produced cooling and this has compensated for the warming effect of our ageing sun. There have been times when compensation was too slow or too fast, and the Earth warmed or cooled, but not once since life first emerged has liquid water completely disappeared from the surface.

Our planet has therefore miraculously moderated climate change for four billion years. This observation led to the development of the Gaia hypothesis that a complex biosphere automatically regulates the environment in its own interests. However, Gaia lacks a credible mechanism and has probably confused cause and effect: a reasonably stable environment is a precondition for a complex biosphere not the other way around.

Other inhabited planets in the universe must also have found ways to prevent global warming. Watery worlds suitable for life will have climates that, like the Earth, are highly sensitive to changing circumstances. The repeated cancelling of star-induced warming by “geobiological” cooling, required to keep such planets habitable, will have needed many coincidences and the vast majority of such planets will have run out of luck long before sentient beings evolved.

However, the universe is immense and a few rare worlds will have had the necessary good fortune. It may just be that Earth is one of those lucky planets – a precious, fragile jewel in space. So, perhaps inevitably, climate change will remain a bane of the continued existence of life on such planets.