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Scientists know that certain bits of DNA on the end of chromosomes called “telomeres” shorten each time the cell divides, playing a role in cell aging and eventual cell death

New research has uncovered how stress levels and diet can affect the biological age of an organism as opposed to chronological age, or calendar years.

For years scientists thought that sequencing DNA would uncover the “gene-for” almost everything, unraveling the mysteries of disease and resulting in new drugs and gene-specific treatments. It didn’t exactly pan out that way.

So to uncover the calculus within the genome, it might take some looking beyond the genome. Genes may contribute a few elements to the inner clock, but they interact within a larger scaffolding of cell processes and environmental factors.

fat cells generally do not generate after puberty -- as your body stores more fat, the number of fat cells remains the same. Each fat cell simply gets bigger!

I do think humans are motivated to daydream about extraterrestrial intelligence, and, to put a finer point on it, extraterrestrial "people." They are motivated to dream about beings very much like them, things tantalizingly exotic but not so alien as to be totally incomprehensible and discomforting. Maybe those imagined beings have more appendages or sense organs, different body plans and surface coverings, but they typically possess qualities we recognize within ourselves: They are sentient, they have language, they use tools, they are curious explorers, they are biological, they are mortal - just like humans. Perhaps that's a collective failure of imagination, because it's certainly not very easy to envision intelligent aliens that are entirely divergent from our own anthropocentric preconceptions. Or perhaps it's more diagnostic of the human need for context, affirmation, and familiarity. Why are people fascinated by their distorted reflections in funhouse mirrors? Maybe it's because when they recognize their warped image, at a subconscious level that recognition reinforces their actual true appearance and identity.

The first pessimistic take is that the differences between independently emerging and evolving biospheres would be so great as to prevent much meaningful communication occurring between them if any intelligent beings they generated somehow came into contact.

The second pessimistic take is that intelligent aliens, far from being incomprehensible and ineffable, would be in fact very much like us, due to trends of convergent evolution, the tendency of biology to shape species to fit into established environmental niches.

It stands to reason that any alien species that managed to embark on interstellar voyages to explore and colonize other planetary systems could, like us, be a product of competitive evolution that had effectively conquered its native biosphere. Their intentions would not necessarily be benevolent if they ever chose to visit our solar system.

The third pessimistic scenario is an extension of the second, and postulates that if we did encounter a vastly superior alien civilization, even if they were benevolent they could still do us harm through the simple stifling of human tendencies toward curiosity, ingenuity, and exploration.

Right now reaching low-Earth orbit generally comes at a cost somewhere between $5,000 to $10,000 per kilogram, depending on which launch vehicle is used. This creates an enormous barrier to making profitable ventures in space or building major space-based infrastructure. It also engenders further high costs in the design, fabrication, and testing of most spaceflight hardware, which due to the high cost to orbit must be made as lightweight and reliable as possible.

If launch costs fall well below $1,000 per kilogram, a host of economic activities that were previously prohibitively expensive should at a stroke become cheap enough to be readily profitable.

I'm an American citizen, so I will focus my comments on the American space program and the American political system. I'm sad to say that in this country, the most powerful nation presently on the planet, space science, exploration, and development are treated as fringe issues at best. Too many politicians, if they consider these issues at all, treat them in one of two ways: Dismissively, as things to be joked about, or cynically, as little more than pork-barrel job programs for their districts, things to be defended purely for the status quo and only given token lip-service when absolutely necessary.

And who can blame them? Look at what happens to politicians when they try to talk seriously and ambitiously about space today. They are lampooned and ridiculed by the media and by their political opponents as starry-eyed idealists who are disconnected from everyday realities.

“I am certainly not saying that Darwinian ideas are wrong,” he explained. “On the contrary, I am just saying that from the perspective of the physics, you might call Darwinian evolution a special case of a more general phenomenon.”

Eugene Shakhnovich, a professor of chemistry, chemical biology and biophysics at Harvard University, are not convinced. “Jeremy’s ideas are interesting and potentially promising, but at this point are extremely speculative, especially as applied to life phenomena,” Shakhnovich said.

England’s theoretical results are generally considered valid. It is his interpretation — that his formula represents the driving force behind a class of phenomena in nature that includes life — that remains unproven. But already, there are ideas about how to test that interpretation in the lab.

“He’s trying something radically different,” said Mara Prentiss, a professor of physics at Harvard who is contemplating such an experiment after learning about England’s work. “As an organizing lens, I think he has a fabulous idea. Right or wrong, it’s going to be very much worth the investigation.”

Hot things cool down, gas diffuses through air, eggs scramble but never spontaneously unscramble; in short, energy tends to disperse or spread out as time progresses.

It increases as a simple matter of probability: There are more ways for energy to be spread out than for it to be concentrated.

cup of coffee and the room it sits in become the same temperature, for example. As long as the cup and the room are left alone, this process is irreversible. The coffee never spontaneously heats up again because the odds are overwhelmingly stacked against so much of the room’s energy randomly concentrating in its atoms.

A plant, for example, absorbs extremely energetic sunlight, uses it to build sugars, and ejects infrared light, a much less concentrated form of energy. The overall entropy of the universe increases during photosynthesis as the sunlight dissipates, even as the plant prevents itself from decaying by maintaining an orderly internal structure.

In Schrödinger’s day, they could solve the equations of thermodynamics only for closed systems in equilibrium.

Jarzynski and Crooks showed that the entropy produced by a thermodynamic process, such as the cooling of a cup of coffee, corresponds to a simple ratio: the probability that the atoms will undergo that process divided by their probability of undergoing the reverse process (that is, spontaneously interacting in such a way that the coffee warms up).

Using Jarzynski and Crooks’ formulation, he derived a generalization of the second law of thermodynamics that holds for systems of particles with certain characteristics: The systems are strongly driven by an external energy source such as an electromagnetic wave, and they can dump heat into a surrounding bath.

Having an overarching principle of life and evolution would give researchers a broader perspective on the emergence of structure and function in living things, many of the researchers said. “Natural selection doesn’t explain certain characteristics,” said Ard Louis, a biophysicist at Oxford University, in an email. These characteristics include a heritable change to gene expression called methylation, increases in complexity in the absence of natural selection, and certain molecular changes Louis has recently studied.

Higher levels of female obesity correlated with higher levels of gender inequality in each nation Of course, that’s not the impression you will get from the admonishments of public-health agencies and wellness businesses.

Yet the scientists who study the biochemistry of fat and the epidemiologists who track weight trends are not nearly as unanimous as Bloomberg makes out. In fact, many researchers believe that personal gluttony and laziness cannot be the entire explanation for humanity’s global weight gain.

Consider, for example, this troublesome fact, reported in 2010 by the biostatistician David B Allison and his co-authors at the University of Alabama in Birmingham: over the past 20 years or more, as the American people were getting fatter, so were America’s marmosets.

‘Virtually in every population of animals we looked at, that met our criteria, there was the same upward trend,’ he told me.

It isn’t hard to imagine that people who are eating more themselves are giving more to their spoiled pets, or leaving sweeter, fattier garbage for street cats and rodents. But such results don’t explain why the weight gain is also occurring in species that human beings don’t pamper, such as animals in labs, whose diets are strictly controlled. In fact, lab animals’ lives are so precisely watched and measured that the researchers can rule out accidental human influence

In rich nations, obesity is more prevalent in people with less money, education and status. Even in some poor countries, according to a survey published last year in the International Journal of Obesity, increases in weight over time have been concentrated among the least well-off. And the extra weight is unevenly distributed among the sexes, too.

The story might go like this: being poor is stressful, and stress makes you eat, and the cheapest food available is the stuff with a lot of ‘empty calories’, therefore poorer people are fatter than the better-off. These wheels-within-wheels are required because the mantra of the thermodynamic model is that ‘a calorie is a calorie is a calorie’: who you are and what you eat are irrelevant to whether you will add fat to your frame. The badness of a ‘bad’ food such as a Cheeto is that it makes calorie intake easier than it would be with broccoli or an apple.

More importantly, ‘things that alter the body’s fat metabolism’ is a much wider category than food. Sleeplessness and stress, for instance, have been linked to disturbances in the effects of leptin, the hormone that tells the brain that the body has had enough to eat.

If some or all of these factors are indeed contributing to the worldwide fattening trend, then the thermodynamic model is wrong.

According to Frederick vom Saal, professor of biological sciences at the University of Missouri, an organic compound called bisphenol-A (or BPA) that is used in many household plastics has the property of altering fat regulation in lab animals.

BPA has been used so widely — in everything from children’s sippy cups to the aluminium in fizzy drink cans — that almost all residents of developed nations have traces of it in their pee. This is not to say that BPA is unique.

Contrary to its popular image of serene imperturbability, a developing foetus is in fact acutely sensitive to the environment into which it will be born, and a key source of information about that environment is the nutrition it gets via the umbilical cord.

It’s possible that widespread electrification is promoting obesity by making humans eat at night, when our ancestors were asleep

consider the increased control civilisation gives people over the temperature of their surroundings.

Temperatures above and below the neutral zone have been shown to cause both humans and animals to burn fat, and hotter conditions also have an indirect effect: they make people eat less.

A study by Laura Fonken and colleagues at the Ohio State University in Columbus, published in 2010 in the Proceedings of the National Academy of Sciences, reported that mice exposed to extra light (experiencing either no dark at all or a sort of semidarkness instead of total night) put on nearly 50 per cent more weight than mice fed the same diet who lived on a normal night-day cycle of alternating light and dark.

A virus called Ad-36, known for causing eye and respiratory infections in people, also has the curious property of causing weight gain in chickens, rats, mice and monkeys.

xperiments by Lee Kaplan and colleagues at Massachusetts General Hospital in Boston earlier this year found that bacteria from mice that have lost weight will, when placed in other mice, apparently cause those mice to lose weight, too.

It might be that every one of the ‘roads less travelled’ contributes to global obesity; it might be that some do in some places and not in others. The openness of the issue makes it clear that obesity isn’t a simple school physics experiment.

In a capitalistic quest for new markets and cheap materials and labour, Europeans take control of the economy in the late 18th or early 19th century. With taxes, fees and sometimes violent repression, their new system strongly ‘encourages’ the farmer and his neighbours to stop growing their own food and start cultivating some more marketable commodity instead – coffee for export, perhaps. Now that they aren’t growing food, the farmers must buy it. But since everyone is out to maximise profit, those who purchase the coffee crop strive to pay as little as possible, and so the farmers go hungry. Years later, when the farmer’s children go to work in factories, they confront the same logic: they too are paid as little as possible for their labour. By changing the farming system, capitalism first removes traditional protections against starvation, and then pushes many previously self-sufficient people into an economic niche where they aren't paid enough to eat well.

Eighty years later, the farmer’s descendants have risen out of the ranks of the poor and joined the fast-growing ranks of the world’s 21st-century middle-class consumers, thanks to globalisation and outsourcing. Capitalism welcomes them: these descendants are now prime targets to live the obesogenic life (the chemicals, the stress, the air conditioning, the elevators-instead-of-stairs) and to buy the kinds of foods and beverages that are ‘metabolic disturbers’.

Wells memorably calls this double-bind the ‘metabolic ghetto’, and you can’t escape it just by turning poor people into middle-class consumers: that turn to prosperity is precisely what triggers the trap.

The ‘unifying logic of capitalism’, Wells continues, requires that food companies seek immediate profit and long-term success, and their optimal strategy for that involves encouraging people to choose foods that are most profitable to produce and sell — ‘both at the behavioural level, through advertising, price manipulations and restriction of choice, and at the physiological level through the enhancement of addictive properties of foods’ (by which he means those sugars and fats that make ‘metabolic disturber’ foods so habit-forming).

One possible response, of course, is to decide that no obesity policy is possible, because ‘science is undecided’. But this is a moron’s answer: science is never completely decided; it is always in a state of change and self-questioning, and it offers no final answers. There is never a moment in science when all doubts are gone and all questions settled,

Faced with signs of a massive public-health crisis in the making, governments are right to seek to do something, using the best information that science can render, in the full knowledge that science will have different information to offer in 10 or 20 years.

It turns out that early farmers were actually less healthy than the surrounding hunter-gatherer populations. So why did the farmers ‘win’ so resoundingly, to the extent that virtually no one on Earth today lives as a hunter-gatherer?

As we settled down into farming villages, and then towns and cities, society became more complicated. Hunter-gatherers, having fewer people in their groups, tend to have fairly simple and egalitarian social structures. A chief perhaps, but certainly not a specialized bureaucracy, a professional army, a priesthood and other trappings of what we call civilization.

The first is the growing power of genetic engineering.

unlike other technologies that have witnessed explosive growth over the past couple of decades, from computers to nanotechnology, the applications of genetics have the potential to affect the biological identity of future generations, through our ability to choose the traits our children – and all subsequent generations – will carry.

The second enormous challenge that we need to face as a result of the events set in motion 10,000 years ago with the development of agriculture is climate change.

The final significant challenge, unlike the other two, is not fundamentally technological in nature, though some of the solutions will likely involve the application of technology. We have now evolved culturally to the point where the entire world is connected in a way it has never been before.

For secular rationality, read loss of faith and certainty. For improving living standards, read increased consumption. For increased social mobility, read loss of traditional roles and threats to vested interests.

The biggest revolution of the past 50,000 years was not the advent of the Internet, the growth of the industrial age out of the seeds of the Enlightenment, or the development of modern methods of long-distance navigation. Rather, it was a seemingly trivial event that happened rather quickly around 10,000 years ago – the dawn of the age of agriculture, when a few people living in several locations around the world decided to stop gathering their food from the land, abiding by limits set in place by nature, and grow their food.

But that raises another question: Could unusual environmental conditions be triggering intergroup chimpanzee killing?

When we first offered the chimps bananas the males seldom fought over their food; …now…there was a great deal more fighting than ever before." (This quote appears in Sussman and Marshack's paper.)

Ian Tattersall, an anthropologist at the American Museum of Natural History, told me that chimpanzee violence is "plausibly related to population stress occasioned by human encroachment."

Researchers have never observed coalitionary killing among bonobos. Noting that bonobos are just as genetically related to us as chimpanzees, Frans de Waal, a primatologist at Emory University, suggested last year in The Wall Street Journal that bonobos may be "more representative of our primate background" than are chimpanzees.

One author, anthropologist Owen Lovejoy of Kent State University, told me that Ardi has triggered a "tectonic shift" in views of human evolution.

There is also no fossil or archaeological evidence that our ancestors fought millions or even hundreds of thousands of years ago. Yes, archaeological digs and modern ethnography have established that warfare was common among pre-state societies, notably hunter–gatherers; our ancestors are thought to have lived as hunter–gatherers since the emergence of the Homo genus two million years ago.

But as the anthropologist Douglas Fry of Åbo Akademi University in Finland pointed out in his book Beyond War: The Human Potential for Peace (Oxford University Press, 2009), the oldest clear-cut relic of group violence is a 13,000-year-old grave along the Nile River in the Jebel Sahaba region of Sudan.

Evidence of earlier lethal human violence is ambiguous, at best.

But most Paleolithic injuries probably resulted from "hunting large animals who object to being speared," Trinkaus told me. "You find a lot of evidence of bumps and bruises and broken bones" among Neandertals and other early humans. "There is absolutely no evidence," Trinkaus says, that "war is continuous back to the common ancestor with chimps."

"I'm good. You're bad," says Kastner. "And they're both doing that at the same time." Kastner describes it as the worst time in any intimate relationship.

About half of the "thinking" neurons in certain regions of the brain, Chattra says, are literally "wiped out."

"Sometimes, parents say, 'What were you thinking?' " says Kastner. "And the joke's on us. They weren't thinking. They were running like wildebeests in the canyon. Just go, go, go. You know, they were flooded and excited and not really thinking through the consequences of their actions."

"It will be small, medium or large, based on the quality" of the self-critique and how much the parents believe their children learned from the mistake, she says. Parents might even have the teenager suggest their own discipline. And there's an added benefit to the teens' writing. It engages the "thinking" part of the brain, and gets the teenager away from the emotional frenzy of the night.

And forget having the last word, she says. "Let them have the last word," Kastner says about the kids.

Human beings evolved in small groups where good relations were vital for survival. People who weren't interested in other people's opinions had trouble staying alive and reproducing. Caring about the opinions of others isn't as immutable as our sexual preferences, but it's very deeply rooted.

To deny a human nature consisting of innate propensities is a far more serious matter than denying facts about quantum mechanics or Einstienian relativity.

She expected her acolytes to think, feel and behave like the heroes of Atlas Shrugged, rather than as human beings. She failed to recognize that many of the weaknesses which plague the human animal are congenital, rooted in biology and the human condition, and that they can never be overcome (assuming they can be overcome at all) if they are not first recognized and dealt with in the open.

Popper’s arguments against determinism are far more complex and sophisticated than Rand’s.

In his book on determinism, Popper mentions an argument issued by the geneticist J.B.S. Haldane. This argument, first introduced by Haldane in 1898, is so similar to Rand’s that one wonders if there isn’t a connection between the two.

it’s not immediately obvious that I can say anything useful about a civilization run by beings vastly more intelligent than us. I’d be like an australopithecine trying to visualize daytime cable TV.

The idea of an AI singularity

if you start trying to visualize a coherent future that includes aliens, telepathy, faster than light travel, or time machines, your futurology is going to rapidly run off the road and go crashing around in the blank bits of the map that say HERE BE DRAGONS.

at least one barkingly implausible innovation will come along between now and 2061 and turn everything we do upside down

My crystal ball is currently predicting that base load electricity will come from a mix of advanced nuclear fission reactor designs and predictable renewables such as tidal and hydroelectric power.

We are, I think, going to have molecular nanotechnology and atomic scale integrated circuitry.

engineered solutions that work a bit like biological systems

Mature nanotechnology is going to resemble organic life forms the way a Boeing 737 resembles thirty tons of seagull biomass.

without a technological civilization questions of network security take second place to where to get a new flint arrowhead.

if we’re still alive in the 26th century you’re welcome to remind me of what I got wrong in this talk.

we’re living through the early days of a revolution in genomics and biology

We haven’t yet managed to raise the upper limit on human life expectancy (it’s currently around 120 years), but an increasing number of us are going to get close to it.

another prediction: something outwardly resembling democracy everywhere.

Since 1911, democractic government by a republic has gone from being an eccentric minority practice to the default system of government world-wide

Democracy is a lousy form of government in some respects – it is particularly bad at long-term planning, for no event that lies beyond the electoral event horizon can compel a politician to pay attention to it

. In general, democratically elected politicians are forced to focus on short-term solutions to long-term problems because their performance is evaluated by elections held on a time scale of single-digit years

Democratic systems are prone to capture by special interest groups that exploit the information asymmetry that’s endemic in complex societies

Finally, representative democracy scales up badly

Nor are governments as important as they used to be.

the US government, the largest superpower on the block right now, is tightly constrained by the international trade system it promoted in the wake of the second world war.

we have democratic forms of government, without the transparency and accountability.

The good news is, we’re a lot richer than our ancestors. Relative decline is not tragic in a positive-sum world.

Assuming that they survive the obstacles on the road to development, this process is going to end fairly predictably: both India and China will eventually converge with a developed world standard of living, while undergoing the demographic transition to stable or slowly declining populations that appears to be an inevitable correlate of development.

a quiet economic revolution is sweeping Africa

In 2006, for the first time, more than half of the planet’s human population lived in cities. And by 2061 I expect more than half of the planet’s human population will live in conditions that correspond to the middle class citizens of developed nations.

by 2061 we or our children are going to be living on an urban middle-class planet, with a globalized economic and financial infrastructure recognizably descended from today’s system, and governments that at least try to pay lip service to democratic norms.

It’s a normative projection

I’m pretty certain that something utterly unexpected will come along and up-end all these projections – something as weird as the world wide web would have looked in 1961.

And while the outer forms of that comfortable, middle-class urban developed-world planetary experience might look familiar to us, the internal architecture will be unbelievably different.

a lot of the buildings are going to be familiar

Automobiles are automobiles, even if the ones he sees look kind of melted

Fashion? Hats are out, clothing has mutated in strange directions

He may be thrown by the number of pedestrians walking around with wires in their ears, or holding these cigarette-pack-sized boxes with glowing screens.

But there seem to be an awful lot of mad people walking around with bits of plastic clipped to their ears, talking to themselves

Our visitor from 1961 is familiar with cars and clothes and buildings

But he hasn’t heard of packet switched networks

Our time traveller from 1961 has a steep learning curve if he wants to understand the technology the folks with the cordless headsets are using.

The social consequences of a new technology are almost always impossible to guess in advance.

For example, we’re currently raising the first generation of kids who won’t know what it means to be lost – everywhere they go, they have GPS service and a moving map that will helpfully show them how to get wherever they want to go.

to our time traveller from 1961, it’s magic: you have a little glowing box, and if you tell it “I want to visit my cousin Bill, wherever he is,” a taxi will pull up and take you to Bill’s house

The whole question of whether a mature technosphere needs three or four billion full-time employees is an open one, as is the question of what we’re all going to do if it turns out that the future can’t deliver jobs.

We’re still in the first decade of mass mobile internet uptake, and we still haven’t seen what it really means when the internet becomes a pervasive part of our social environment, rather than something we have to specifically sit down and plug ourselves in to, usually at a desk.

the shape of the future depends on whether whoever provides the basic service of communication

funds their service by charging for bandwidth or charging for a fixed infrastructure cost.

These two models for pricing imply very different network topologies.

This leaves aside a third model, that of peer to peer mesh networks with no actual cellcos as such – just lots of folks with cheap routers. I’m going to provisionally assume that this one is hopelessly utopian

the security problems of a home-brew mesh network are enormous and gnarly; when any enterprising gang of scammers can set up a public router, who can you trust?

Let’s hypothesize a very high density, non-volatile serial storage medium that might be manufactured using molecular nanotechnology: I call it memory diamond.

wireless bandwidth appears to be constrained fundamentally by the transparency of air to electromagnetic radiation. I’ve seen some estimates that we may be able to punch as much as 2 tb/sec through air; then we run into problems.

One thing you can do trivially with that kind of capacity is full lifelogging for everyone. Lifelogging today is in its infancy, but it’s going to be a major disruptive technology within two decades.

the resulting search technology essentially gives you a prosthetic memory.

Lifelogging offers the promise of indexing and retrieving the unwritten and undocmented. And this is both a huge promise and an enormous threat.

Lifelogging raises huge privacy concerns, of course.

The security implications are monstrous: if you rely on lifelogging for your memory or your ability to do your job, then the importance of security is pushed down Maslow’s hierarchy of needs.

if done right, widespread lifelogging to cloud based storage would have immense advantages for combating crime and preventing identity theft.

whether lifelogging becomes a big social issue depends partly on the nature of our pricing model for bandwidth, and how we hammer out the security issues surrounding the idea of our sensory inputs being logged for posterity.

at least until the self-driving automobile matches and then exceeds human driver safety.

In particular, there’s a huge boom in new technologies for high speed gene sequencing.

full genome sequencing for individuals now available for around US $30,000, and expected to drop to around $1000–3000 within a couple of years.

Each of us is carrying around a cargo of 1–3 kilograms of bacteria and other unicellular organisms, which collectively outnumber the cells of our own bodies by a thousand to one.

Only the rapid development of DNA assays for SARS – it was sequenced within 48 hours of its identification as a new pathogenic virus – made it possible to build and enforce the strict quarantine regime that saved us from somewhere between two hundred million and a billion deaths.

we can expect eventually to see home genome monitoring – both looking for indicators of precancerous conditions or immune disorders within our bodies, and performing metagenomic analysis on our environment.

In each of these three examples of situations where personal privacy may be invaded, there exists a strong argument for doing so in the name of the common good – for prevention of epidemics, for prevention of crime, and for prevention of traffic accidents. They differ fundamentally from the currently familiar arguments for invasion of our data privacy by law enforcement – for example, to read our email or to look for evidence of copyright violation. Reading our email involves our public and private speech, and looking for warez involves our public and private assertion of intellectual property rights …. but eavesdropping on our metagenomic environment and our sensory environment impinges directly on the very core of our identities.

With lifelogging and other forms of ubiquitous computing mediated by wireless broadband, securing our personal data will become as important to individuals as securing our physical bodies.

the shifting sands of software obsolescence have for the most part buried our ancient learning mistakes.