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Arsenic-Based Life Possible, But Not Certain

December 2, 2010 / Klint Finley

Mono Lake

Boing Boing’s Maggie Koerth-Baker adds a quick dose of realism and clarity to this morning’s NASA announcement:

Not everybody agrees that this research proves the bacteria are capable of replacing phosphate with arsenic. You can read more about that debate in the really nicely done article at Nature News that I’m quoting above.

Also, even if this is proof that phosphate isn’t necessary for life, we still don’t know whether the bacteria in question actually replace their phosphate in the wild. Right now, this is something humans are convincing it to do in a petri dish. That’s why it’s not entirely fair to say that weird life has been discovered—all this paper does (if it stands up to the coming onslaught of scrutiny) is show that weird life is, in fact, possible.

But that’s still a pretty big deal. However you slice it, this is an extremely interesting little bacterium. It isn’t alien. It still has the same basic DNA structure we all know and love. It just might be able to use different chemicals to build that old, familiar structure. And that’s pretty cool on its own.

Also, Mono Lake sounds pretty cool:

A couple of years ago, scientists found bacteria in California’s Mono Lake that used arsenic compounds, rather than water, as an ingredient of photosynthesis. In fact, there’s been a lot of weird life research centered around Mono Lake. Hot, salty, low in oxygen, and high in lots of other useful chemicals, the Lake has been described as a here-and-now model of the old primordial soup.

Boing Boing: Weird life found on Earth—kind of, maybe

Photo by Chris Streeter

NASA Discovers New Life on Earth: Bacteria with Arsenic-Based DNA

December 2, 2010 / Klint Finley

Arsenic

Update: Please see this update on how, although this research is significant, it doesn’t necessarily indicate that there is arsenic-based bacteria in the wild.

Evidence that the toxic element arsenic can replace the essential nutrient phosphorus in biomolecules of a naturally occurring bacterium expands the scope of the search for life beyond Earth, according to Arizona State University scientists who are part of a NASA-funded research team reporting findings in the Dec. 2 online Science Express.

It is well established that all known life requires phosphorus, usually in the form of inorganic phosphate. In recent years, however, astrobiologists, including Arizona State University professors Ariel Anbar and Paul Davies, have stepped up conversations about alternative forms of life. […]

Davies has previously speculated that forms of life different from our own, dubbed “weird life,” might even exist side-by-side with known life on Earth, in a sort of “shadow biosphere.” The particular idea that arsenic, which lies directly below phosphorous on the periodic table, might substitute for phosphorus in life on Earth, was proposed by Wolfe-Simon and developed into a collaboration with Davies and Anbar. Their hypothesis was published in January 2009, in a paper titled “Did nature also choose arsenic?” in the International Journal of Astrobiology.

PhysOrg: Deadly arsenic breathes life into organisms

Is Schizophrenia Caused by Retroviruses?

November 22, 2010 / Klint Finley

DNA by Micah Baldwin

Mind blowing research that indicates that schizophrenia, bipolar disorder, and multiple sclerosis could be caused by a retrovirus and triggered by other infections such as toxoplasmosis:

The facts of schizophrenia are so peculiar, in fact, that they have led Torrey and a growing number of other scientists to abandon the traditional explanations of the disease and embrace a startling alternative. Schizophrenia, they say, does not begin as a psychological disease. Schizophrenia begins with an infection.

The idea has sparked skepticism, but after decades of hunting, Torrey and his colleagues think they have finally found the infectious agent. […]

After eight years of research, Perron finally completed his retrovirus’s gene sequence. What he found on that day in 1997 no one could have predicted; it instantly explained why so many others had failed before him. We imagine viruses as mariners, sailing from person to person across oceans of saliva, snot, or semen—but Perron’s bug was a homebody. It lives permanently in the human body at the very deepest level: inside our DNA. After years slaving away in a biohazard lab, Perron realized that everyone already carried the virus that causes multiple sclerosis. […]

Through this research, a rough account is emerging of how HERV-W could trigger diseases like schizophrenia, bipolar disorder, and MS. Although the body works hard to keep its ERVs under tight control, infections around the time of birth destabilize this tense standoff. Scribbled onto the marker board in Yolken’s office is a list of infections that are now known to awaken HERV-W—including herpes, toxoplasma, cytomegalovirus, and a dozen others. The HERV-W viruses that pour into the newborn’s blood and brain fluid during these infections contain proteins that may enrage the infant immune system. White blood cells vomit forth inflammatory molecules called cytokines, attracting more immune cells like riot police to a prison break. The scene turns toxic.

Discover Magazine: The Insanity Virus

(Thanks Paul)

Previously: Virus Behind Insanity?

Why War? Biological vs. Cultural Explanations

November 11, 2010 / Klint Finley

Fighting

John Horgan, writing for Scientific American, asks the big question: why do humans wage war? He’s previously rejected the “demonic males” theory, and has found Margaret Meade theory more satisfactory:

Many scholars solve this problem by combining Darwin with gloomy old Thomas Malthus. “No matter where we happen to live on Earth, we eventually outstrip the environment,” the Harvard archaeologist Steven LeBlanc asserts in Constant Battles: Why We Fight (Saint Martin’s Griffin, 2004). “This has always led to competition as a means of survival, and warfare has been the inevitable consequence of our ecological-demographic propensities.” Note the words “always” and “inevitable.” […]

The best answer I’ve found comes from Margaret Mead, who as I mentioned in a recent post is often disparaged by genophilic researchers such as Wrangham. Mead proposed her theory of war in her 1940 essay “Warfare Is Only an Invention—Not a Biological Necessity.” She dismissed the notion that war is the inevitable consequence of our “basic, competitive, aggressive, warring human nature.” This theory is contradicted, she noted, by the simple fact that not all societies wage war. War has never been observed among a Himalayan people called the Lepchas or among the Eskimos. In fact, neither of these groups, when questioned by early ethnographers, was even aware of the concept of war.

In discussing the Eskimos Mead distinguished between individual and group violence. Eskimos were “not a mild and meek people,” she noted. They engaged in “fights, theft of wives, murder, cannibalism,” often provoked by fear of starvation. “The personality necessary for war, the circumstances necessary to goad men to desperation are present, but there is no war.”

Mead next addressed the claim that war springs from “the development of the state, the struggle for land and natural resources of class societies springing, not from the nature of man, but from the nature of history.” Here Mead seems to invoke Marx as well as Malthus. Just as the biological theory is contradicted by simple societies that don’t fight, Mead wrote, so the theory of “sociological inevitability” is contradicted by simple societies that do fight. Hunter–gatherers on the Andaman Islands “represent an exceedingly low level of society,” but they have been observed waging wars, in which “tiny army met tiny army in open battle.”

Scientific American: Margaret Mead’s war theory kicks butt of neo-Darwinian and Malthusian models

(photo by Polina Sergeeva)

(Thanks Bill!)

Ancient Nubians Drank Antibiotic Beer?

September 3, 2010 / Klint Finley

ancient brew

A chemical analysis of the bones of ancient Nubians shows that they were regularly consuming tetracycline, most likely in their beer.

A chemical analysis of the bones of ancient Nubians shows that they were regularly consuming tetracycline, most likely in their beer. The finding is the strongest evidence yet that the art of making antibiotics, which officially dates to the discovery of penicillin in 1928, was common practice nearly 2,000 years ago.
The research, led by Emory anthropologist George Armelagos and medicinal chemist Mark Nelson of Paratek Pharmaceuticals, Inc., is published in the American Journal of Physical Anthropology.

“We tend to associate drugs that cure diseases with modern medicine,” Armelagos says. “But it’s becoming increasingly clear that this prehistoric population was using empirical evidence to develop therapeutic agents. I have no doubt that they knew what they were doing.”

PhysOrg: Ancient brew masters tapped drug secrets

(Thanks Paul!)

Introduction to Mind-Altering Parasites

September 2, 2010 / Klint Finley

My wife on mind-altering parasites:

There are dozens of similar behavior-altering parasites, each as fascinating as the next. Most of these parasites are specialized to a single species of host. The large majority infect insects or creatures on the low end of the evolutionary scale. There are some exceptions, including Toxoplasma gondii which lives in cats and infects humans. Toxoplasma gondii also infects rats and makes them lose their fear of cats- an infected rodent will waltz right up to cat’s hangout spot, only to be eaten and live inside the cat’s intestines long enough to get back to its preferred host, a human. Studies are still being done on the effects of Toxoplasmosis, but it seems to produce introverted and anti-social tendencies in the host, along immune and neurological problems.

Prime Surrealestate: Mind-Altering Parasites

How Technology Made Us Humans

August 31, 2010 / Klint Finley

The Man of Year Million

In his book, “The Artificial Ape,” anthropologist and archaeologist Timothy Taylor makes the startling claim that we did not make tools, tools made us.

He reminds us that the oldest stone tools we’ve found are 2.5 million years old. But the genus to which we belong, Homo, is only 2.2 million years old, at least according to the current fossil record. Our species, Homo sapiens, has been around for less time than the gap between tool creation and our genus.

In a fascinating interview with New Scientist, Taylor believes “earlier hominids called australopithecines were responsible for the stone tools . . . The tools caused the genus Homo to emerge.”

How does that reverse the human-technology equation? Taylor believes that the creation of tools – in his example a sling to carry an infant – is “how encephalisation took place in the genus Homo.” The creation of technology to take care of infants allowed them to be born more helpless. In other words, the development of initial tech allowed evolutionary forces to shape us in a particular fashion. In fact, perhaps forced them to do so.

ReadWriteWeb: How Technology Made Us Humans

Will our brains shrink due to our external ones? Not necessarily. The current trend is a demand for more and more intelligent and educated people to operate and program those machines. Even though I’d like to see computers get easier to operate and program, I would still expect see a demand for humans to do increasingly complex work with them.

Bacteria Survives in Space, Without Oxygen, for a Year and a Half

August 29, 2010 / Klint Finley

space-bacteria

The bugs were put on the exterior of the space station to see how they would cope in the hostile conditions that exist above the Earth’s atmosphere.

And when scientists inspected the microbes a year and a half later, they found many were still alive.

These survivors are now thriving in a laboratory at the Open University (OU) in Milton Keynes.

The experiment is part of a quest to find microbes that could be useful to future astronauts who venture beyond low-Earth orbit to explore the rest of the Solar System. […]

This type of research also plays into the popular theory that micro-organisms can somehow be transported between the planets in rocks – in meteorites – to seed life where it does not yet exist.

BBC: Beer microbes live 553 days outside ISS

Interestingly, the bacteria selected weren’t known extremophiles, they were selected apparently at random.

E.O. Wilson Proposes New Theory of Social Evolution

August 29, 2010 / Klint Finley

Ants

For decades, selflessness — as exhibited in eusocial insect colonies where workers sacrifice themselves for the greater good — has been explained in terms of genetic relatedness. Called kin selection, it was a neat solution to the conundrum of selflessness in what was supposedly an every-animal-for-itself evolutionary battle.

One early proponent was now-legendary Harvard biologist E.O. Wilson, a founder of modern sociobiology. Now Wilson is leading the counterattack. […]

The researchers offer their own alternative theory, based on standard natural selection, but with a twist: After starting with a focus on a single founder, selection moves to the level of colony. From this perspective, a worker ant is something like a cell — part of a larger evolutionary unit, not a unit unto itself.

“Our model proves that looking at a worker ant and asking why it is altruistic is the wrong level of analysis,” said Tarnita. “The important unit is the colony.”

Wired Science: E.O. Wilson Proposes New Theory of Social Evolution

Making brains: Reverse engineering the human brain to achieve AI

August 25, 2010 / Klint Finley

Brain

An introduction to the concepts and problems with reverse engineering the human brain:

The ongoing debate between PZ Myers and Ray Kurzweil about reverse engineering the human brain is fairly representative of the same debate that’s been going in futurist circles for quite some time now. And as the Myers/Kurzweil conversation attests, there is little consensus on the best way for us to achieve human-equivalent AI.

That said, I have noticed an increasing interest in the whole brain emulation (WBE) approach. Kurzweil’s upcoming book, How the Mind Works and How to Build One, is a good example of this—but hardly the only one. Futurists with a neuroscientific bent have been advocating this approach for years now, most prominently by the European transhumanist camp headed by Nick Bostrom and Anders Sandberg.

While I believe that reverse engineering the human brain is the right approach, I admit that it’s not going to be easy. Nor is it going to be quick. This will be a multi-disciplinary endeavor that will require decades of data collection and the use of technologies that don’t exist yet. And importantly, success won’t come about all at once. This will be an incremental process in which individual developments will provide the foundation for overcoming the next conceptual hurdle.

Sentient Developments: Making brains: Reverse engineering the human brain to achieve AI

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