How About a New Theory of Evolution with Less Natural Selection? 


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In early November, a group of preeminent biologists, doctors, anthropologists, and computer scientists met in London to consider making a major change to the concept of evolutionary biology introduced by Charles Darwin in Origin of the Species in 1859. It’s not that they’re interested in throwing out the idea of natural selection. It’s just that they think recent research suggests it doesn’t account for evolution all by itself. This isn’t the first time such a revision has happened, actually. And it’s not clear that it will this time: Conference co-host Kevin Laland told Quantamagazine mid-conference, “I think it’s going quite well,” Laland said. “It hasn’t gone to fisticuffs yet.”

The current understanding of evolution, known as “modern evolutionary synthesis,” is itself a combination of natural selection and the 1865 genetics work of Gregor Mendel, published six years after Origin of the Species.

mendel's peas

Mendel’s peas

The modern synthesis emerged in the 1930s and 1940s, and it’s what’s taught in schools today. It states that evolution is the product of small genetic variations (Mendel’s contribution) that survive, or not (Darwin’s process of natural selection).

Some of the scientists at the Royal Society’s “New Trends in Evolutionary Biology” meeting say that this isn’t quite the case, and that there’s a third element that needs to be incorporated: Behavior and environment can also cause evolutionary changes. Carl Zimmer of Quanta, who attended the conference, says, “The researchers don’t argue that the modern synthesis is wrong — just that it doesn’t capture the full richness of evolution.”

To that end some attendees at the conference proposed a new understanding they call the “extended evolutionary synthesis.” What it adds to Darwin’s and Mendel’s work is an awareness of epigenetics.

The word “epigenetics” means “in addition to changes in genetic sequence.” According to science journalist Tabitha M. Powledge, “Broadly speaking, epigenetics is how nurture shapes nature.” The field looks at inheritable genetic changes that don’t involve the changing of a DNA sequence, but rather the activation or deactivation of genes via the epigenome, a layer of chemical tags covering and shaping the structure of a genome to turn individual genes on or off depending on the purpose of a cell, using a variety of chemical processes. The University of Utah has a great video explaining what an epigenome is.

epigenetic mechanisms

Epigenetic mechanisms (NIH)

According to the University of Utah, “The epigenome dynamically responds to the environment. Stress, diet, behavior, toxins, and other factors regulate gene expression.”

Scientists used to believe that when a offspring is born, it starts with a clean epigenomic slate. This turns out not to always be the case, at least in plants and fungi, and maybe in invertebrates. Some epigenetic tags survive, and thus “epigenetic inheritance” may play a role in the organism’s evolution. There’s some evidence it also occurs in vertebrates, but the jury is still out, and the presence of epigenetic inheritance is difficult to establish. A trait may turn out to be the result of obscure or subtle DNA changes, or a common environment may cause the persistence of a trait in a subsequent generation rather than epigenetic inheritance.

Still, epigeneticists hope the field can help explain evolutionary changes that don’t seem to be accounted for by modern evolutionary synthesis.

For example, speaking at the Royal Society was Melinda Zeder, who talked about the way in which modern synthesis fails to provide a reason for mankind’s turning to agriculture 10,00 years ago and its ensuing evolutionary impact. Growing crops may have taken years, so there could not have been a short-term evolutionary benefit to it. As Zeder told Quanta, “You don’t get the immediate gratification of grabbing some food and putting it in your mouth.” It’s also been theorized that a climate shift caused agriculture to bloom, but there’s no evidence of such a shift.

first farmers

Zeder suggests we take a different view of humans at the time as creative individuals who deliberately decided to change their environment by farming, pushing human evolution in that new direction. This process is called “niche construction,” and it’s more than just a human behavior; think beavers and their dams.

Not everyone agrees that epigenetics warrants a revision to the understanding of evolution, and there were plenty of skeptics at the Royal Society conference. Not everyone agreed with the conclusions of some experiments that putatively demonstrated epigenetic at work, and others noted that epigenetics undervalues the flexibility, or “plasticity,” provided by plentiful genetic variations. Biologist Douglas Futuyma suggested the appeal of epigenetics was that it changes the organism from a passive receiver of genetics changes to an active participant in evolution. “I think what we find emotionally or aesthetically more appealing is not the basis for science,” he said.

As Laland noted to Quanta, “This is likely the first of many, many meetings.”

Where’s the Proof in Science? There Is None


UNDERSTANDING RESEARCH: What do we actually mean by research and how does it help inform our understanding of things? Those people looking for proof to come from any research in science will be sadly disappointed.

As an astrophysicist, I live and breathe science. Much of what I read and hear is couched in the language of science which to outsiders can seem little more than jargon and gibberish. But one word is rarely spoken or printed in science and that word is “proof”. In fact, science has little to do with “proving” anything.

These words may have caused a worried expression to creep across your face, especially as the media continually tells us that science proves things, serious things with potential consequences, such as turmeric can apparently replace 14 drugs, and more frivolous things like science has proved that mozzarella is the optimal cheese for pizza.

 Surely science has proved these, and many other things. Not so!

The Way of the Mathematician

A statue of Euclid with something very interesting added to his scroll. (Garrett Coakley/Flickr)

Mathematicians prove things, and this means something quite specific. Mathematicians lay out a particular set of ground rules, known as axioms, and determine which statements are true within the framework.

A statue of Euclid with something very interesting added to his scroll. (Garrett Coakley/Flickr)

A statue of Euclid with something very interesting added to his scroll. (Garrett Coakley/Flickr)

One of best known of these is the ancient geometry of Euclid. With only a handful of rules that define a perfect, flat space, countless children over the last few millenia have sweated to prove Pythagoras’s relation for right-angled triangles, or that a straight line will cross a circle at most at two locations, or a myriad of other statements that are true within Euclid’s rules.

Whereas the world of Euclid is perfect, defined by its straight lines and circles, the universe we inhabit is not. Geometrical figures drawn with paper and pencil are only an approximation of the world of Euclid where statements of truth are absolute.

Over the last few centuries we’ve come to realise that geometry is more complicated than Euclid’s, with mathematical greats such as Gauss, Lobachevsky and Riemann giving us the geometry of curved and warped surfaces.

In this non-Euclidean geometry, we have a new set of axioms and ground-rules, and a new set of statements of absolute truth we can prove.

These rules are extremely useful for navigating around this (almost-) round planet. One of Einstein’s (many) great achievements was to show that curving and warping spacetime itself could explain gravity.

Yet, the mathematical world of non-Euclidean geometry is pure and perfect, and so only an approximation to our messy world.

Just What Is Science?

But there is mathematics in science, you cry. I just lectured on magnetic fields, line integrals and vector calculus, and I am sure my students would readily agree that there is plenty of maths in science.

Albert Einstein. (Wikimedia/Doris Ulmann)

And the approach is same as other mathematics: define the axioms, examine the consequences.

Einstein’s famous E=mc2, drawn from the postulates of how the laws of electromagnetism are seen by differing observers, his special theory of relativity, is a prime example of this.

But such mathematical proofs are only a part of the story of science.

The important bit, the bit that defines science, is whether such mathematical laws are an accurate description of the universe we see around us.

To do this we must collect data, through observations and experiments of natural phenomena, and then compare them to the mathematical predictions and laws. The word central to this endeavour is “evidence”.

The Scientific Detective

The mathematical side is pure and clean, whereas the observations and experiments are limited by technologies and uncertainties. Comparing the two is wrapped up in the mathematical fields of statistics and inference.

Many, but not all, rely on a particular approach to this known as Bayesian reasoning to incorporate observational and experimental evidence into what we know and to update our belief in a particular description of the universe.

The only way is down for these apples. (Don LaVange/Flickr)

The only way is down for these apples. (Don LaVange/Flickr)

 

Here, belief means how confident you are in a particular model being an accurate description of nature, based upon what you know. Think of it a little like the betting odds on a particular outcome.

Our description of gravity appears to be pretty good, so it might be odds-on favourite that an apple will fall from a branch to the ground.

But I have less confidence that electrons are tiny loops of rotating and gyrating string that is proposed by super-string theory, and it might be a thousand to one long-shot that it will provide accurate descriptions of future phenomena.

So, science is like an ongoing courtroom drama, with a continual stream of evidence being presented to the jury. But there is no single suspect and new suspects regularly wheeled in. In light of the growing evidence, the jury is constantly updating its view of who is responsible for the data.

But no verdict of absolute guilt or innocence is ever returned, as evidence is continually gathered and more suspects are paraded in front of the court. All the jury can do is decide that one suspect is more guilty than another.

What Has Science Proved?

In the mathematical sense, despite all the years of researching the way the universe works, science has proved nothing.

Every theoretical model is a good description of the universe around us, at least within some range of scales that it is useful.

But exploring into new territories reveals deficiencies that lower our belief in whether a particular description continues to accurately represent our experiments, while our belief in alternatives can grow.

Will we ultimately know the truth and hold the laws that truly govern the workings of the cosmos within our hands?

While our degree of belief in some mathematical models may get stronger and stronger, without an infinite amount of testing, how can we ever be sure they are reality?

I think it is best to leave the last word to one of the greatest physicists, Richard Feynman, on what being a scientist is all about: “I have approximate answers and possible beliefs in different degrees of certainty about different things, but I’m not absolutely sure of anything.”

Richard Dawkins: Religion Is a Meme and Religious Beliefs Are “Mind-Parasites”


We are used to the idea that diseases can be passed down from person to person. One gets ill and gives the sickness to everyone he meets, and so on till you have an epidemic. But what about ideas? Can ideas infect societies like viruses?

Any Internet-aware person has seen memes. They usually feature a photo with a quote or caption. They can also be popular videos or articles. Interestingly, the evolutionary biologist Richard Dawkins coined the term “meme” in his 1976 book “The Selfish Gene” to describe an idea, style or behavior that spreads within a culture. A meme is basically a unit of culture and it can spread virally. A meme can be Grumpy Cat or Hitler’s mad thought that an Aryan super-nation must be built at the expense of millions of exterminated people.

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How do memes spread? Richard Dawkins talks about it this way in his book:

“Just as genes propagate themselves in the gene pool by leaping from body to body via sperm or eggs, so memes propagate themselves in the meme pool by leaping from brain to brain via a process which, in the broad sense, can be called imitation. If a scientist hears, or reads about, a good idea, he passes it on to his colleagues and students. He mentions it in his articles and his lectures. If the idea catches on, it can be said to propagate itself, spreading from brain to brain.”

According to Dawkins, memes can be quite powerful in transmitting information, often becoming dangerous, as anyone who’s been featured in an Internet fail meme can attest.

“Memes should be regarded as living structures, not just metaphorically but technically,” writes Dawkins in “The Selfish Gene”. “When you plant a fertile meme in my mind, you literally parasitize my brain, turning it into a vehicle for the meme’s propagation in just the way that a virus may parasitize the genetic mechanism of a host cell. And this isn’t just a way of talking — the meme for, say, ‘belief in life after death’ is actually realized physically, millions of times over, as a structure in the nervous systems of people all over the world.”

But can a meme evolve into an even more powerful force, a destructive mass affliction caused by the spread of thoughts? One example can be seen in the case of religion. A noted atheist, Dawkins regards religion as a meme that has taken over human brains for millennia. In his 1991 essay “Viruses of the Mind,” Dawkins describes religious beliefs as “mind-parasites” while believers are “faith sufferers” or “patients”.  He sees several conditions to be present in such people. One is that the belief is not based on reason.

“The patient typically finds himself impelled by some deep, inner conviction that something is true, or right, or virtuous: a conviction that doesn’t seem to owe anything to evidence or reason, but which, nevertheless, he feels as totally compelling and convincing. We doctors refer to such a belief as “faith,” explains Dawkins. “Patients typically make a positive virtue of faith’s being strong and unshakable, in spite of not being based upon evidence. Indeed, they may fell that the less evidence there is, the more virtuous the belief.”

What’s significant to Dawkins is that being afflicted by a belief is likely to make you intolerant of others who don’t share the same view.

“The sufferer may find himself behaving intolerantly towards vectors of rival faiths, in extreme cases even killing them or advocating their deaths,” he writes in the essay.

Whatever one’s views on religion may be, Dawkins’s thoughts have value when applied to other social phenomena. The current election cycle in the United States has produced its share of belief-based division, with opposing sides slinging often-untrue facts at each other, while becoming more and more entrenched in their own opinions.

The polarization has become extreme, especially in the passions of some supporters of the candidates, who increasingly view the world in apocalyptic, highly defensive ways, especially as they are bombarded by contrasting memes. Such division can be viewed as thought viruses that are tearing up the “normal” functioning of the American society.

Could meme-driven social viruses bring often-necessary adjustments to the intellectual status quo? In a normal election year that is easy to assert. This year it is possible that the relatively open nature of democratic processes has allowed some unsavory ideas to spread unchecked, especially as the most common method of how modern ideas are transferred – the media – has come under fire for being biased. In such a climate, a destructive idea has a greater likelihood of taking hold.

Still, even fearing this, it’s hard to see a preventive remedy for these weak spots, short of running a totalitarian regime. One can argue that the strongly-interconnected and social-media-obsessed modern societies are now particularly vulnerable to thought viruses. And the threats are likely to keep coming, well into the future past the crazy election cycle.

You can hear Richard Dawkins talk about applying the study of memetics to religion here:

 

Tesla’s Autopilot System Saves Life In Netherlands, Applies Brakes Before The Driver Can React.


All those who think driving sucks, here’s some good news – the future is driver-less. So you can just sit back, relax and let the computer do the driving. And there can’t be a stronger case for this than what happened in Netherlands a couple of days ago.

Out on the highway, the ‘Autopilot’ system as Tesla calls it, applied brakes on its own, even before the driver could react. Look at the footage and ‘you’ don’t really realise there’s anything wrong, even though the system sounds the alarm for an impending disaster. And the very next second the car ahead rams the SUV which flips a couple of times before coming to a rest. It was like car could predict the future!

Tesla autopilot

As shocking and unbelievable as it sounds, this is what cars of the future will be like. Tesla has been touting the ‘Autopilot’ as a life saving feature and is a precursor to fully autonomous cars that are just a few years away. While Volvo has has ‘City Safety’ self braking system on its cars, it’s limited to speeds below 30 kph. We’ve experienced this and it is uncanny how the car stops even before we can lift our foot to apply the brakes. There’s also adaptive cruise control on some cars that slows down when it detects traffic ahead.

Tesla’s ‘Autopliot’ goes a step ahead and combines these together. Radar and cameras mounted on the car read the road conditions and traffic ahead to speed up or slow down. A computerised system is quicker than a human any day and therefore safer.

Tesla autopilot

Hopefully more cars will have features like this as standard. Not only will this reduce the number of accidents on our roads, but also save lives.

Heres Sundar Pichais Cockroach Theory That Will Teach You A Thing Or Two About Life


Sundar Pichai continues to make global news after becoming Google’s CEO. Stories about his past, schooling and college days are viral. Well at least in India they are. Here’s another story, or rather a speech by Sundar Pichai, that is being massively shared for the past few days. It’s a speech about the ‘cockroach theory’ for self development. Here’s how the theory goes:

Sundar Pichai Cockroach Theory

“At a restaurant, a cockroach suddenly flew from somewhere and sat on a lady.

She started screaming out of fear.

With a panic stricken face and trembling voice, she started jumping, with both her hands desperately trying to get rid of the cockroach.

Her reaction was contagious, as everyone in her group also got panicky.

The lady finally managed to push the cockroach away but …it landed on another lady in the group.

Now, it was the turn of the other lady in the group to continue the drama.

The waiter rushed forward to their rescue.

In the relay of throwing, the cockroach next fell upon the waiter.

The waiter stood firm, composed himself and observed the behavior of the cockroach on his shirt.

When he was confident enough, he grabbed it with his fingers and threw it out of the restaurant.

Sipping my coffee and watching the amusement, the antenna of my mind picked up a few thoughts and started wondering, was the cockroach

responsible for their histrionic behavior?

If so, then why was the waiter not disturbed?

He handled it near to perfection, without any chaos.

It is not the cockroach, but the inability of the ladies to handle the disturbance caused by the cockroach that disturbed the ladies.

I realized that, it is not the shouting of my father or my boss or my wife that disturbs me, but it’s my inability to handle the disturbances caused by their shouting that disturbs me.

It’s not the traffic jams on the road that disturbs me, but my inability to handle the disturbance caused by the traffic jam that disturbs me.

More than the problem, it’s my reaction to the problem that creates chaos in my life.

Lessons learnt from the story:

I understood, I should not react in life.

I should always respond.

The women reacted, whereas the waiter responded.

Reactions are always instinctive, whereas responses are always well thought of, just and right to save a situation from going out of hands, to avoid cracks in relationship, to avoid taking decisions in anger, anxiety, stress or hurry.

A beautiful way to understand…………LIFE.”

–         Sundar Pichai

Well that’s quite a bit of an insight into the mind of the person who runs Google or better said, the internet.

NASA Will Pay You 18000 USD To Stay In Bed And Smoke Weed For 70 Straight Days.


We all get lazy from time to time and just want to quit everything, crawl back to bed under a layer of blankets and live there until we feel better. We might feel a bit guilty but a relaxing day in bed sounds awesome. Even though it’s a luxury which few of us can afford, at least we can all fantasize about it.

 If you’re one of those who are in desperate need of some peace and relaxation, NASA might offer you the perfect opportunity to do so and get payed on top of it. But it may involve a bit more relaxation than you’re prepared for.

NASA has put out an ad looking for people who’re willing to take part in their “Rest Studies” – a study which will require participant to spend 70 straight days in bed, relaxing and smoking different types of cannabis, for which they will receive a salary of 18.000 USD. During the relaxation period participants are allowed to read books, play games, Skype and smoke weed. They can do whatever they want as long as it involves staying in bed, week after week, earning a cool 1200 USD per week.nasa-will-pay-you-18000-usd-to-stay-in-bed-and-smoke-weed-for-70-straight-day

So what is the exact purpose of these studies?

These studies have the purpose of figuring out the best way to preserve astronauts’ health and safety during periods of prolonged space travel. Complete rest and relaxation is the best way to stimulate zero gravity in space because zero gravity actually means zero weight or strain on your muscle. Additionally, they wanted to see how marijuana will affect the body in such an environment.

 nasa-will-pay-you-18000-usd-to-stay-in-bed-and-smoke-weed-for-70-straight-day

The Rest Study is a very convenient way to examine the changes our body endures during space travel.

This study is designed to achieve three core tasks:

  • Examining how the astronauts’ changing physiology in space could affect the process of certain missions.
  • Examining if the astronauts’ physiological state could affect their ability to perform in particular tasks.
  • Preparing countermeasures to combat any impairment that these physiological conditions may impose.

The study’s participants were divided into two groups: exercising and non-exercising.

The exercising group will have to exercise (on a specially designed equipment to maintain the laying down position and smoke cannabis), while the non-exercising group will just have to lie down and relax completely.

The entire study will last somewhere between 97 and 105, depending on whether you’re in the exercising or non-exercising group.

Once the study begins, during the initial 13 days (non-exercising subjects) and 21 days (exercising subjects) you can move around the bed rest area freely, in and out of bed. But once this period ends, for the next 70 days you’ll be forbidden from leaving your bed. For 70 days you’ll have to lie down, with your feet up, kick back and enjoy! You’ll get out of bed only for a few tests and nothing more. 70 days of complete lazing.

During the study, NASA will have to conduct bone, muscle and heart tests, as well as tests of your circulatory and nervous systems, your nutritional condition, and your body’s immunity system.

But is it worth it?

You may not think so at first, but spending two whole months in bed can be really excruciating. At some point you may feel like you can’t take it anymore but at least you can rest assured that your efforts will help in the advancement of human space travel.

This will probably be your only opportunity to say that you’ve actually helped send the first astronauts to Mars by just being your lazy self and doing nothing in particular but lying flat on your back.

Source:

http://mysteriousearth.net

How scientists are preparing for a world without antibiotics.


5 strategies for beating antibiotic resistance.

Antimicrobial peptides (the pink ribbons in this illustration), which are part of the innate immune system in all domains of life, can destroy microbes (blue and green) and also call white blood cells (the marbled white and red balls) to help fight an infection.

Ella Marushchenko

The drugs that have protected us from virulent bacteria for more than seventy years are slowly losing their edge, and we need new weapons. Disease-causing bacteria are becoming impervious to antibiotics that once wiped them out, including some drugs once considered last-resort.

Antibiotic-resistant bacteria infect at least 2 million people every year in the United States, killing 23,000. Some researchers estimate that if left unchecked, superbugs will kill 10 million people every year and cost the global economy $100 trillion by the year 2050.

“A lot of things that we take for granted right now, like say a C-section or a hip replacement or organ transplant…without having the antibiotics, these kinds of things will become really difficult,” says François Franceschi, a program officer for therapeutic development in the Bacteriology and Mycology Branch of the National Institute of Allergy and Infectious Diseases.

Those with weakened immune systems would be particularly vulnerable, but anyone could be at risk in a post-antibiotic world. “People are talking about potential for a post-antibiotic era where the antibiotics that we have available these days don’t work against simple infections like a small wound or a cut,” says César de la Fuente, a bioengineer at MIT.

To fight resistant bacteria, we are turning to new allies such as viruses that only attack bacteria, nanoparticles, and tiny proteins based on those produced by the immune systems of different organisms. Each tool comes with advantages and drawbacks, so researchers are exploring many approaches.

“A lot of people in the field have been now trying to look for alternative strategies that add to our arsenal,” says Timothy Lu, also of MIT. It’s “not that any one of them on their own is going to be the one silver bullet that’s going to cure bacteria for the rest of our lives, but more to be able to come at the problem from a variety of different ways.”

Here are some of the ways we will send our new allies into the fray in the war on superbugs.

Disarm the invaders

Bacteria don’t always need to be killed in order to be neutralized. Some treatments attack germs indirectly by targeting the weapons that make them virulent. “The bacteria will still be there but the consequences of the infection will not be severe, and then that will give the immune system…a chance to combat that infection,” Franceschi says.

If your drug doesn’t actually kill bacteria, they have less incentive to evolve resistance against it. “The development of resistance is going to take a lot longer because the bacteria isn’t actively fighting that,” Francsechi says.

Many bacteria secrete toxins that damage the cells of their host. One common type are called pore-forming toxins, which punch holes in cells. They’re produced by MRSA, Escherichia coliListeria, the bacteria that cause anthrax, and the venom of snakes, scorpions and sea anemones.

Liangfang Zhang has come up with a way to nullify these toxins. “You take away the weapon [and] they can become much weaker,” says Zhang, a nanoengineer at the University of California, San Diego. He coats nanoparticles with an irresistible target—membranes plucked from red blood cells. The red blood cell shell acts as a decoy, drawing in toxins that would otherwise attack healthy cells. “They serve as a sponge to suck up all these toxins,” Zhang says.

In their first exploration, the nanosponges soaked up the toxins without harming mice. This year, Zhang’s work with nanoparticles as decoys was one of 24 projectsawarded funding by the National Institutes of Health. He hopes to begin human clinical trials in the next year to two.

tiny sponge

A tiny sponge, about 85 nanometers across, can soak up toxins produced by bacteria.

Liangfang Zhang Laboratory, UC San Diego

Nanoparticles, which are often made from plastics or metals such as silver, can also impair bacteria by disrupting their protective cell membranes or causing DNA damage. Nanoparticles are easy to work with because they essentially build themselves. “You control the temperature, you control the solvent and so on, these molecules will automatically assemble into the nanoparticle,” Zhang says.

Nanoparticles may be more expensive than traditional antibiotics. And directing them to the right spot in a body is also a challenge. Another concern is making sure that the nanoparticles are made from materials that won’t trigger an immediate immune response, and will break down over time so they don’t accumulate in the body.

“There are still ongoing questions about the long term safety of some of these things,” Lu says. “That being said I think using nanoparticles really can have an antimicrobial effect that’s very potent.”

Special delivery

Alternative therapies can also be used to make existing antibiotics more effective. Scientists are investigating how to use nanoparticles to deliver cancer drugs and antibiotics.

Antibiotics spread throughout the body and are toxic in high doses. With nanoparticles, you can deploy concentrated hits of drugs. Thousands of drug molecules can be stuffed inside a single nanoparticle.

“They can easily just stick to the membrane and constantly release the drug right onto the bacteria,” Zhang says. This means a larger, more effective cargo can be used without boosting the total drug dose.

“This can overwhelm the bacteria’s resistance mechanisms, because they haven’t developed resistance mechanisms against this drug storm,” Zhang says.

A problem with nanoparticles, and many other tools, is that the immune system sees them as a threat. “The size is very much like viruses,” Zhang says. “Our body actually is trained to clear these nanoparticles or viruses if you don’t protect them.”

Zhang and his colleagues have camouflaged nanoparticles in jackets made from the membranes of platelets—cell fragments that help blood clot. “From outside it looks just like a mini cell,” Zhang says.

Certain bacteria are attracted to platelets, which they hijack to mask themselves from the immune system. Platelet-coated nanoparticles turn the table on these bacteria, luring the interlopers in only to blast them with drugs.

“All the nanoparticles will specifically go to the bacteria and release the drug,” says Zhang. He has used the platelet-coated particles to treat mice infected with a strain of MRSA, which is resistant to many antibiotics.

Direct attack

Sometimes, however, no subterfuge is needed. Many of the alternatives to traditional antibiotics can kill bacteria outright. One strategy is designing manmade versions of antimicrobial peptides (AMPs), which are a part of the innate immune response in microbes, plants and animals (such as Tasmanian devils). These compounds attack a pathogen’s membrane and may also wreak havoc inside the cell.

In a recent project, de la Fuente collaborated with Lu and others to select a non-toxic AMP discovered in simple marine animals called tunicates. The team added a few amino acids to this template, improving its ability to treat mice infected with antibiotic-resistant E. coli and MRSA. The souped-up AMP also galvanized the rodents’ immune systems by calming inflammation and calling for backup in the form of white blood cells.

Antimicrobial peptides can vanquish a wide range of pathogens, and bacteria have difficulty developing resistance to them. “In comparison with conventional antibiotics, these peptides are more effective in many cases,” de la Fuente says.

Colonies of Acinetobacter baumannii, bacteria that can develop resistance against the last-resort antibiotic colistin. Researchers protected mice from A. baumanniiby designing many-armed particles that latch onto bacteria like burrs and break apart the membrane. Like antimicrobial peptides, the tiny stars are built from amino acids. But their bulkier size seems to make them less dangerous against healthy cells. “Essentially we now have a star which kills the bacteria but doesn’t kill the host,” says coauthor Greg Qiao, of the University of Melbourne.

AMPs are made from relatively short strings of amino acids, the building blocks of proteins. This makes them straightforward (albeit time-consuming and expensive) to build. “We have yet to bring down the cost,” de la Fuente says. Researchers are exploring ways to build AMPs more cheaply by programming microbes to make them instead of relying on a machine.

However, there are concerns that AMPs might turn on host cells. And as with many alternatives to antibiotics, sending them to the right location at a high enough concentration to be effective is also a challenge. “What’s more feasible in the short term is probably topical application,” de la Fuente says. “We would formulate these peptides into, say, a cream that you could apply [if] you have a skin infection or an open wound.” They could also be used to coat tables, computers, surgical instruments, or catheters to prevent them from being colonized by germs.

Re-sensitization

Another way to weaken bacteria is to knock out the resistance they have cultivated against antibiotics. Viruses that are specialized to prey on bacteria, called bacteriophages, can be tapped for these missions.

Phages are extremely effective bacteria-killers, but researchers can use genetic engineering to give them new skills to bring to battle, and to restore bacteria’s sensitivity to traditional drugs.

Reprogrammed phages may lock onto bacteria carrying genes that confer antibiotic resistance, erasing this ability or killing the bacteria. With the resistant germs knocked out or defused, the remaining population is vulnerable to antibiotics.

Another way bacteria resist antibiotics is by secreting compounds that create a barrier called a biofilm that drugs cannot penetrate. Phages can be engineered to chew up the biofilm (Lu and de la Fuente’s redesigned antimicrobial peptide also shows promise for biofilm busting).

In the wild, phages can slay bacteria directly. “Some phages will introduce their DNA into the bacteria and in order to liberate themselves… just chew up the cell wall, for example, and sort of explode the cell,” Lu says. Others act as parasitic hitchhikers.

Modified phages can also wipe out bacteria. “What we have been doing is trying to engineer phages that can go into a bacteria and kill them in a very targeted way,” Lu says. “You can introduce new functions into the phages to make them more powerful antimicrobial agents.”

Phages were actually discovered about 100 years ago. They were eclipsed by antibiotics in the United States, although some areas of Eastern Europe have continued to use them. Currently, there are no FDA-approved phages, although clinical trials are underway. Phages seem to be about as effective as antibiotics in treating humans, although there is not yet clinical data to confirm this.

One advantage of these viruses is that they can make more of themselves (as viruses are wont to do once placed inside a host). “You can put a small amount in and kill a lot of bacteria,” Lu says. And because they need living bacterial cells to reproduce, they’re unlikely to stick around once their hosts have been wiped out.

However, like other alternatives, phages may trigger the immune system. “If you inject any virus or any foreign peptide into a person, there’s always a chance there’s going to be a reaction,” Lu says. Another worry is that some phages may pick up genes related to antibiotic resistance and transfer them to other bacteria.

But they’re unlikely to harm human tissue. “Phages do not replicate in human cells, and I haven’t seen any reports where they’ve been shown to have any negative consequences,” Lu says. “There are tons of phages inside of us already, it’s not like these things are foreign to us.”

A personal touch

Some alternative therapies may be tailored to fight specific germs. Here, again, phages are ideal candidates. “They are basically the natural enemy of bacteria,” Lu says. Generally, “if you find a bacteria, you can find a phage against it.”

Traditional antibiotics often kill bacteria indiscriminately—including those in our body’s natural microbiome that play key roles in our health. This can leave an opening for opportunists like Clostridium difficile to colonize the body. “You don’t want to carpet bomb the gut and kill all the bacteria,” Franceschi says.

Viruses offer a more personalized approach. “You can try to spare the good bacteria…while still being able to kill the bad bacteria,” Lu says.

But this specificity is a double-edged sword. To cover enough of the different bacteria that might be infecting a patient, multiple viruses will have to be mixed into a cocktail. And, while phages aren’t particularly expensive to grow, cocktails laced with many viruses make manufacturing more complicated. “The traditional way of doing that has been to go into nature and just find all the different phages and mix them together,” Lu says. “It poses a lot of challenges in terms of practical development.”

Lu is working on an NIH-funded project to make cocktails full of phages built from the safe scaffold. By tweaking the region that dictates what a phage infects, you can target different bacteria without modifying the rest of the virus. “That allows you to take phages and point them in different directions,” Lu says. “That’s one of the last remaining hurdles for phage therapy to become widespread, the ability to make sort of a well defined cocktail and tune it so it will go after bacteria you care about.”

Even so, it’s difficult to craft a tailored medicine without knowing what is causing an infection. “If you go to a doctor, they’re…not going to feel confident giving you a narrow spectrum treatment if they don’t actually know what the bacteria is,” Lu says.

Doctors need speedier diagnostics so they can figure out which bacteria they are going after, and whether it is resistant to traditional antibiotics. Lu and his colleagues have engineered phages for quick, cheap diagnostics. When they infect their target bacteria, they light up by producing the same protein that fireflies use. Expose phages to sample from your patient, and “you can simply read out whether the sample is glowing or not, and then you know whether that bacteria was present in that sample,” Lu says.

Doctors can then use tailored therapies, whether they are made from phages or other tools. “You really need that option of diagnostics or none of the vision of having narrow spectrum antimicrobials is going to work,” Lu says.

A diverse armory

These aren’t the only weapons we are adding to our cache. Researchers are also exploring other options, like sending other bacteria to fight pathogens, continuing to hunt for new antibiotics (often inspired by compounds bacteria use to kill each other in the wild), and using antibodies, among other things.

“You probably can’t just rely on one technology, or one thing, to eradicate the entire problem,” Zhang says. Tackling superbugs from many angles, sometimes even combining new tactics with traditional therapies, will give doctors options to choose from.

It’s going to be a few years before these new tools are adopted for widespread use. And for awhile, these alternative antimicrobials will be directed to cases where antibiotics are no longer working. “Antibiotics, when they do work, are so cheap and so awesome that I think getting clinicians to move away from that wholesale would be really hard,” Lu says. “Long term, my hope…is really that it will replace a lot of the broad spectrum antimicrobials because…messing up our microbiome is bad for us in a lot of different ways, and I think the only solution for that is really to get to targeted therapy.”

Sending a diverse array of weapons against bacteria will slow down the development of resistance – the wide use of individual antibiotics has made it relatively simple for the bacteria they target to evolve defenses – but it won’t make the problem go away.

“Bacteria are essentially very plastic and vey well equipped to evolve really quickly,” Franceschi says. “Bacteria will keep evolving and you will always need something new.”

This 700,000-Year-Old Human Skull Challenges The Prevailing Theory Of Human Evolution


this-700000-year-old-human-skull-challenges-the-prevailing-theory-of-human-evolution

The “Petralona man”, or “Archanthropus of Petralona”, is a 700,000-year-old human skull discovered in 1959. Since then, scientists have been trying to trace this skull’s origin, a process that has caused considerable controversy.

The skull, indicating the oldest human “europeoid” (presenting European traits), was embedded in a cave’s wall in Petralona, near Chalkidiki in Northern Greece. The cave, rich in stalactites and stalagmites, was accidentally located by a shepherd. Dr. Aris Poulianos, an expert anthropologist, member of the UNESCO’s International Union of Anthropological and Ethnological Sciences and founder of the Anthropological Association of Greece, was assigned a research on the cave and skull.

Before that, Dr. Poulianos was already known for his thesis on “The origin of the Greeks. His thesis was based on craniological and anthropometrical studies of Modern Greek populations, which proved that modern Greeks are related to ancient Greeks and that they are not the descendants of Slavic nations. After the extensive study on the 700,000-year-old skull, he concluded that the “Petralona man” was not connected to the species that came out of Africa. His arguments were mainly based on the skull’s almost perfect orthography, the shape of its dental arch, and the occipital bone construction. According to the “Out of Africa” theory, “anatomically modern humans” known as “Homo sapiens” originated in Africa between 200,000 and 100,000 years ago before spreading to the rest of the world. This theory was related to the fact that most prehistoric fossils were found in Africa.

In 1964, two German researchers, anthropologist E. Breitinger and paleontologist O. Sickenberg, who were invited to Greece, suggested that the skull was actually 50,000 years old, thus rejecting Dr. Poulianos’ theory. Moreover, Breitinger claimed that the skull belonged to the “first African out of Africa”. A few years later, in 1971, US Archaeology magazine confirmed Poulianos’ statement. According to the scientific magazine, the existence of a cave dating back more than 700,000 years and human presence in almost every geological layer were ascertained. Additionally, the magazine affirmed that human presence became evident from the discovery of Paleolithic tools of the same age and the most ancient traces of fire that was ever lit by human hand. The research continued from 1975 to 1983, when the excavation stopped and findings remained inaccessible to study until 1997.

Today, 50 years after the discovery of the “Petralona man”, modern methods ofabsolute chronology confirm Dr. Poulianos’ theory. Most academics believe that the skull belongs to an archaic hominid with strong European traits and characteristics of Homo erectus, Neanderthals and sapiens, but they distinguish it from all these species. This incredible discovery raises new questions onhuman evolution, and certainly challenges the “Out of Africa” theory.

References:

  1. http://www.ancient-origins.net/human-origins-science/human-skull-challenges-out-africa-theory-001283
  2. http://anthro.palomar.edu/homo2/mod_homo_1.htm
  3. http://onlinelibrary.wiley.com/doi/10.1111/j.1475-4754.1992.tb00483.x/abstract
  4. http://www.sciencedirect.com/science/article/pii/0305440379900025

A possible explanation for why people find it hard to maintain eye contact when talking


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A pair of researchers with Kyoto University has found a possible explanation for why people sometimes have trouble maintaining eye contact when talking with someone face-to-face. In their paper published in the journal Cognition, Shogo Kajimura and Michio Nomura describe experiments they carried out with volunteers to learn more about how the phenomenon works and then discuss their findings.

To better understand what is going on in the brain during conversation, the researchers enlisted the assistance of 26 volunteers who were asked to participate in a common word-association game in which a person was shown a word (a noun) and was then asked to offer an immediate response (a verb), e.g. when given the word “ball,” a reply might be the word “throw.” In the lab, the volunteers interacted with a face on a computer (that sometimes looked away) as they played the game with different types of words that the researchers had preselected—some were easy while others were more difficult—coming up with a verb for “sky,” for example, can be difficult for some because of the lack of choices, while coming up with a response to a word like “leaf” may be difficult because it has so many options to choose from.

The researchers then compared responses to the words with how long it took a volunteer to respond and their tendency to break eye contact. They found that the volunteers were likely to take more time when responding to harder words, but not as much time if they broke eye contact. This, the research pair suggest, indicates that the dual task of maintaining eye contact (and the inherent intimate connection it involves) while also racking the brain for a word to meet the request is just too demanding—to save itself, the  pushes for breaking so it can focus exclusively on finding a word that will fulfill the obligation.

 Abstract
Although eye contact and verbal processing appear independent, people frequently avert their eyes from interlocutors during conversation. This suggests that there is interference between these processes. We hypothesized that such interference occurs because both processes share cognitive resources of a domain-general system and explored the influence of eye contact on simultaneous verb generation processes (i.e., retrieval and selection). In the present experiment, viewing a movie of faces with eyes directed toward the viewer delayed verbal generation more than a movie of faces with averted eyes; however, this effect was only present when both retrieval and selection demands were high. The results support the hypothesis that eye contact shares domain-general cognitive resource with verb generation. This further indicates that a full understanding of functional and dysfunctional communication must consider the interaction and interference of verbal and non-verbal channels.

Scientists say radio signals from deep space could be aliens


Scientists say radio signals from deep space could be aliens

Scientists may have found proof that E.T. really is phoning home — in the form of powerful radio signals, which have been detected repeatedly in the same exact location in space.

Astronomy experts with the Green Bank Telescope in West Virginia and the Arecibo Observatory in Puerto Rico have discovered six new fast radio bursts (FRBs) emanating from a region far beyond our Milky Way galaxy, according to a recent report in the Astrophysical Journal.

The discovery — made in the direction of the constellation Auriga — is significant considering the fact that at least 17 FRBs have now been detected in this area. It is also the only known instance in which these signals have been found twice in the same location in space.

The region where the signals are coming from, dubbed FRB 121102 by scientists, is about 3 billion light years away from Earth.

Five of the recently found FRBs were detected with the Green Bank Telescope, while the other was recorded by the Arecibo Observatory, “for a total of 17 bursts from this source,” the report says.

The signals were also found earlier this year and in 2012.

According to experts, the FRBs could be the result of two things: solar flares from a neutron star or extra-terrestrials. But it’s still too early to tell.

“Whether FRB 121102 is a unique object in the currently known sample of FRBs, or all FRBs are capable of repeating, its characterization is extremely important to understanding fast extragalactic radio transients,” the scientists write in their report.

In 2015, physicist John Learned, with the University of Hawaii at Manoa, and Michael Hippke, with the Institute for Data Analysis, published a research paper arguing that repeating FRB waves had a 1 in 2,000 chance of being coincidental.

They claimed the radio bursts either came from a man-made spy satellite or a super-dense star, which would regularly emit bursts of radio waves.

Earlier this year, a team of astronomers from Laval University in Quebec published a report saying they had detected strange signals in a small cluster of stars.

Using data from the Sloan Digital Sky Survey, the pair analyzed the spectra of 2.5 million different stars and discovered at least 234 that were producing the signals.

“We find that the detected signals have exactly the shape of an ETI [extraterrestrial intelligence] signal,” wrote Ermanno Borra and Eric Trottier. “Although unlikely … there is also a possibility that the signals are due to highly peculiar chemical compositions in a small fraction of galactic halo stars.”

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