The courtroom is hushed.

A teenage boy has been slain, riddled with bullets during a drive-by shooting, and there, on the witness stand, is his crying mother. She's understandably weeping, wracked by the senseless killing of her darling son. Even worse, she witnessed it all.

"Ma'am, is the man who murdered your son present here today?" the prosecutor questions.

Through the tears, streaming freely, their flow rekindled from having to relive and recount such a horrible event, she manages a nod.

"Can you point him out for us?"

A pause, followed by emphatic pointing at the defendant.

"That's the man! He killed my baby!"

Eyewitness testimony has been a central facet of the American judicial system for centuries. Spirited, dramatic exchanges between attorney and witness are what draw us to courtroom dramas and news stories about pretty women who murder their boyfriends.

There's scant evidence more damning than the sworn statement of a bereaved mother who firmly asserts the guilt of the defendant, especially if such evidence is corroborated by other eyewitnesses.

But eyewitness testimony is merely the product of human memory, and decades of scientific evidence have demonstrated that memory is glaringly fallible.

"All our memories are reconstructed memories," forensic psychologist Scott Fraser explained at TEDxUSC last May. "They are the product of what we originally experienced and everything that's happened afterwards. They're dynamic. They're malleable. They're volatile..."

And they can easily be corrupted. According to Fraser:

"Under the best of observation conditions, the absolute best, we only detect, encode and store in our brains bits and pieces of the entire experience in front of us... So now, when it's important for us to be able to recall what it was that we experienced, we have an incomplete [memory], and what happens? ...The brain fills in information that was not there, not originally stored, from inference, from speculation, from sources of information that came to you, as the observer, after the observation. But it happens without awareness such that you... aren't even cognizant of it occurring."

Since 1992, The Innocence Project has exonerated 306 innocent individuals who were mistakenly convicted of a crime. In three-quarters of these cases, incorrect eyewitness testimony sent those people to prison, by far and away the most common reason. What's startling is that in the vast majority of these cases, witnesses weren't lying. They profoundly and genuinely believed that the people they accused were the perpetrators of the crimes.

This can happen for a lot of reasons. For one, crimes are often emotional and traumatic experiences, and such emotion can have a marked effect on memory. In a study published in February, University of Texas psychologists found that subjects who viewed a video of a mugging were able to recall the event and describe the perpetrator more vividly than subjects who simply watched a video of a conversation, providing more details and ascribing more certainty to their descriptions.

However, in a second experiment, the researchers found that vividness did not correlate with accurate recall. Subjects who witnessed the crime were less able than subjects who watched a conversation to recognize the people involved from a photographic lineup.

False memories can also arise throughout the judicial process. Investigators can easily influence -- intentionally or unintentionally -- the memory of eyewitnesses. Rudimentary verbal or nonverbal affirmations can cause witnesses to become surer of their memories. Suggestive questions by prosecutors can lead to the emergence of novel, erroneous details in witnesses' memories, and cause witnesses to "recall" events that may have never actually happened.

The key, Fraser reminds us, is to be cautious. "The accuracy of our memories is not measured in how vivid they are nor how certain you are that they're correct," he said.

But we can do more than simply be vigilant of our memory's shortcomings. Given its fallibility, one could go so far as to argue that limits should be placed on eyewitness testimony. Perhaps it should be restricted in cases where forensic analysts can determine that vision was hindered, such as in crowds or at night? Maybe more than one eyewitness should be required for such testimony to be allowed in court? Maybe eyewitness accounts should be disallowed altogether in capital trials?

One simple action that can be taken is to mandate double-blind lineups in police stations. This means that the investigator conducting a photo or live lineup will not be aware of who the suspect is. That way, he or she won't be able to influence the witness, knowingly or unknowingly.

We would also be wise to follow New Jersey's example. There, judges are now required to inform juries that "certain factors about an eyewitness's circumstances at time of the offense could render the testimony less reliable. Those factors include the stress the eyewitness was under, the duration of the event, lighting, distance, the eyewitness's focus on a weapon, and cross-racial identification."

Such a basic reminder is undeniably warranted. In a 2011 nationwide survey of 1,838 individuals, 37.1% of respondents were found to believe that "the testimony of one confident eyewitness should be enough evidence to convict a defendant of a crime."

Such thinking is clearly faulty. The truth is not what somebody believes it to be, no matter how adamantly they swear it to be so. Our court system must be insulated from the fallibility of memory.

(Image: Swearing in a Witness via Shutterstock)

Melanoma is a potentially deadly cancer derived from specialized cells in our skin called melanocytes. These cells produce a pigment, melanin, that comes in two different varieties: Eumelanin, which is brown or black, and pheomelanin, which is red. Dark skin contains a lot of eumelanin, while our lips contain a lot of pheomelanin.

Redheads, such as the awesomely hilarious Conan O'Brien (as well as the less-than-awesome Carrot Top) have a lot of pheomelanin. This gives him his characteristic red hair, and as Conan frequently points out, his disturbingly pale skin. For years, scientists believed that pale skin explained why redheads were particularly susceptible to melanoma.

But that is probably not the entire story. Now, researchers explain in the journal BioEssays that pheomelanin itself may cause skin cancer. How? The authors propose two different, non-mutually exclusive hypotheses, both of which involve depleting a cell's antioxidant reserves.

First, the authors suggest that pheomelanin produces carcinogenic substances called "reactive oxygen species" (ROS) -- possibly even in the absence of UV light. These nasty molecules cause DNA damage, and it is for this reason that doctors tell us to eat foods rich in antioxidants (which help neutralize them). However, for various reasons, the researchers don't believe that ROS produced by pheomelanin damages DNA directly; instead, they think that pheomelanin-induced ROS uses up the cell's antioxidant reserves, leaving it vulnerable to other forms of oxidative stress.

The second hypothesis is that the synthesis of pheomelanin diverts cysteine, a type of amino acid, away from the synthesis of glutathione, an important antioxidant that also contains cysteine. If a cell contains less glutathione, it may be more susceptible to oxidative damage.

We want to laugh with Conan for a long time. While he capitalizes on his unsightly, freckled skin and cartoonish hair to make us chuckle, let's hope that he also makes time to visit the dermatologist.

Source: Ann M. Morgan, Jennifer Lo, David E. Fisher. "How does pheomelanin synthesis contribute to melanomagenesis?" BioEssays. Published online 7-May-2013. DOI: 10.1002/bies.201300020

(Photo: AP)

Venus has always captured the attention of humanity. Of all the objects that adorn our night sky, it's the brightest, excluding the Moon.

Peering through his telescope in the early 17th century, Italian astronomer Galileo Galilei found Venus to be almost featureless. What he saw was Venus' defining, impenetrable layer of thick clouds, obscuring the surface and shrouding the planet in mystery, a mystery quite open to speculation. As summarized by Carl Sagan in Cosmos, one of the most outlandish, yet surprisingly common lines of speculative reasoning went a little like this:

"I can't see a thing on the surface of Venus. Why not? Because it's covered with a dense layer of clouds. Well, what are clouds made of? Water, of course. Therefore, Venus must have an awful lot of water on it. Therefore, the surface must be wet. Well, if the surface is wet, it's probably a swamp. If there's a swamp, there's ferns. If there's ferns, maybe there's even dinosaurs."

The original observation was effectively a lack of an observation. The conclusion was dinosaurs.

For decades and decades, this faulty logic played out harmlessly, roiling imaginations and powering the pens of science fiction writers. Published in 1895, Gustavus W. Pope's Journey to Venus weaves the tale of a fantastical trek to Earth's sister planet, placing Lieutenant Frederick Hamilton and his companion, the Martian princess Suhlamia, in a lush Venutian landscape inhabited by vicious, dinosaur-like beasts. "Exciting adventures, hairbreadth escapes, and perilous vicissitudes" ensue, according to the book's publisher.

In 1922, fantasies of a wet, swampy Venus started to fade. Astronomers analyzing the visible light reflected from the planet's atmosphere found no signs of the wavelengths which would have been given off by oxygen or water. Venus, they proposed, may instead be barren and dusty, a desert-like place.

Venus is, of course, named after the Roman goddess of love and beauty, and this new, scientifically modern depiction wasn't nearly romantic or poetic enough for novelists. So what did many of them do? They simply ignored it. Even as late as the 1950s, writers were still describing the planet as wet and rainy. Ray Bradbury's The Long Rain told the story of four men who crash-landed on the planet and were subsequently driven insane by the unceasing precipitation.

"It was a hard rain, a perpetual rain," Bradbury wrote, "a sweating and steaming rain; it was a mizzle, a downpour, a fountain, a whipping in the eyes, an undertow at the ankles; it was a rain to drown all rains and the memory of rains."

We now conclusively know that there's no rain on Venus, not even a drizzle. The planet's sizzling environment, sporting temperatures in excess of 800 degrees Fahrenheit, vaporized liquid water long ago. With this knowledge, we can revise the aforementioned line of reasoning to reach a more correct conclusion:

There is no liquid water. Therefore, there are no ferns. Therefore, there are no dinosaurs.

The act of pooping is a smelly subject, one we humans discreetly relegate to a small porcelain "chair." Atop this throne, locked behind closed doors, amidst the din of a bathroom fan, we do our business in private. Rarely a peep is spoken about poop in public, unless accompanied by inane fart noises. And this is unfortunate, because human feces, while repulsive in sight and smell, are incredibly fascinating!

Human excrement may be a waste product, but it's not altogether valueless. Molded and formed through digestion, feces are composed (PDF) primarily of water, but also of fibers, dead bacteria, fat, inorganic material, and undigested proteins. This mixture, when dried, contains approximately five calories per gram, so it's no wonder that dung sustains a vast world of organisms, including bacteria, fungi, and insects. Life dumps. Somebody's got to clean up the mess.

Human feces rarely reach fungi or insects, however. Instead, they are flushed away to sewage treatment facilities, where they can be feasted upon by colonies of aerobic bacteria housed in large silos. But before waste embarks upon the journey created by modern sanitation, it must first be excreted.

When leaving the anus, feces can come in all sorts of shapes and sizes depending upon the time spent within the large intestine. The type of stool can be very informative to physicians; that's why scientists have classified seven types of stools. They're outlined in the blush-worthy Bristol Stool Chart, seen below.

The typical human being poops about once per day, excreting approximately one ounce of waste for every twelve pounds of body weight. If the lifetime fruits of this regular labor were gathered and piled, the typical American would own a stinky mound weighing almost 27,000 pounds!

Most of this waste is just as you might picture it: brown, slimy, and smelly. But occasionally, human feces can take on some rather exotic hues. If one consumes Prussian blue to treat radiation poisoning, or imbibes exorbitant amounts of grape soda, then that individual may find himself or herself crapping blue. Stranger still, a blockage of the bile ducts -- often caused by gallstones -- coupled with gastrointestinal bleeding can produce stools of scintillating metallic silver.

Silver stools are shocking, but even more eye-opening (and unpalatable) is what comes out of the butts of newborn human babies. Surprise: it's actually not feces! Composed of the materials ingested by the baby from its time spent in the uterus -- often epithelial cells, mucus, amniotic fluid, and bile -- the substance is called meconium. Meconium has the sticky texture of tar, is olive green in hue, and is thankfully odorless.  The same cannot be said for infants' later stools, however.

Blessedly, babies don't stay babies forever. But as soiled diapers give way to training potties, a rare condition called encopresis may manifest in which children develop a fear of pooping. There are a variety of treatment methods and a bounty of books available to help, sporting friendly titles like "The Gas We Pass: The Story of Farts," "I Can't, I Won't, No Way!", and the pithily-dubbed "Potty."

From its smell to the tacky humor it engenders, poop is something we all have to deal with. While we may not appreciate its looks, we can still acknowledge the fascinating science behind it.

(Images: 1. Bristol Chart by Kyle Thompson via Wikimedia Commons 2. Silver Stool by  Herbert L. Fred, MD and Hendrik A. van Dijk via CNX)

As the 1928 Presidential Election played out, the United States was turbulently embroiled in Prohibition. Though support for the act was rapidly waning, Republican presidential nominee Herbert Hoover still endorsed it as an "experiment noble in purpose."

Ironically, at that same time, chemists employed by the federal government were conducting experiments of a more disquieting nature. Enforcement of Prohibition was not going well at all. Citizens across the nation openly flouted the law, notorious crime syndicates ran rampant, and alcoholism rates were soaring. The Federal Government was aware that much of the available spirits originated from stolen industrial alcohol -- used, for example, in household cleaners, perfume, and cosmetics. Sixty million gallons were stolen each year to supply the nation's drinkers! So by 1926, government chemists concocted ten poisonous "denaturing formulas" to be added to the alcohols. These contained ominous chemicals like gasoline, benzene, cadmium, nicotine, ether, formaldehyde, chloroform, and acetone. Prohibition advocates and officials believed that if they made the alcohol undrinkable, imbibers would be forced to abandon their immoral habits. The government defended this effort as "law enforcement." In truth, it was mass poisoning.

In 1927, the pioneering forensic scientist Alexander Gettler, a toxicologist for the City of New York, reported that in the previous year 1,200 New Yorkers had been sickened or blinded by the government's poisoned alcohol, and another 400 had died. Even before these perturbing statistics came to light, Gettler's boss, the now legendary medical examiner Charles Norris, was already incensed with the Federal Government's actions:

"The government knows it is not stopping drinking by putting poison in alcohol... yet it continues its poisoning processes, heedless of the fact that people determined to drink are daily absorbing that poison. Knowing this to be true, the United States government must be charged with the moral responsibility for the deaths that poisoned liquor causes, although it cannot be held legally responsible."

Most of the denaturing formulas' deadly power came not from the myriad additives, but from the simple supplementation of more alcohol. That's because the type utilized here was methanol, sharply dissimilar to the more benign ethanol that we're accustomed to today. If ingested, as little as 10 mL of methanol can result in blindness through the destruction of the optic nerve. About 100 mL is lethal.

The perniciousness of methanol arises from how it's broken down by the body. While the liver's enzymes quickly convert ethanol into acetaldehyde and then acetyl -- the latter of which can be used by the body for energy -- methanol, when broken down, turns into formaldehyde and formic acid, two substances quite unkind to living human tissue. Formic acid actually exists naturally in bee and ant venom.

Gettler and Norris weren't the only people infuriated with Washington's abhorrent poisoning policy. Newspapers across the nation decried the government as a mass poisoner and "an accessory to murder." The collective rage was fueled by a glaring fact: the policy primarily affected the poor. While common citizens literally drank themselves to death on cheap, toxic liquors in backroom speakeasies, the wealthy enjoyed quality cocktails and spirits derived from ethanol, served at colorful parties and luxurious gatherings. 

Herbert Hoover, who, as you might recall, labeled prohibition as a "noble experiment," was in the latter classification. In fact, when serving as the Secretary of Commerce, he would regularly stop by the Belgian Embassy -- technically on foreign soil and thus exempt from Prohibition -- and enjoy some of their fine spirits. They were imported, naturally.

Author's Note: This piece was inspired and primarily sourced from Deborah Blum's The Poisoner's Handbook, which is one of the finest works of historical journalism and nonfiction storytelling that I have read. Check it out!

(Image: Dumping Alcohol from Orange County Archives via Wikimedia Commons)

The German Socio-Economic Panel (GSOEP) is a longitudinal study that's been tracking 12,000 households and 20,000 individuals since 1984. Each year, the members complete in-depth surveys tracking all sorts of data. Some of these gauge life satisfaction and keep the researchers up-to-date on major life changes. From this bounty of information, researchers have produced a number of intriguing findings, including the chart below:


What the graph shows is an increase in relative life satisfaction in the years before and leading up to marriage, but a marked decrease in the years following. Marriage, it would seem, is making people miserable.

But that, of course, is not necessarily true. If marriage really were so unpleasant, then far fewer people would be doing it. Instead, what the table more likely displays is the near futility of measuring life satisfaction with any sort of accuracy.

Let's look at the table a different way. Instead of interpreting a causal effect (which is incorrect), the graph may be more indicative of a decision-making heuristic at work. In other words, people are subconsciously taking a mental shortcut to assess overall life satisfaction, basing their opinion on easily retrievable information.

As explained by psychologist Daniel Kahneman, "...the score that you quickly assign to your life is determined by a small sample of highly available ideas, not by carefully weighting the domains of your life."

For example, in an amusing experiment conducted in 1983, a team led by noted psychologist Norbert Schwarz asked subjects to rate their overall life satisfaction on both sunny and rainy days. Those interviewed on a bright, sunny day reported being more satisfied with their lives in general compared with those interviewed on an overcast, rainy day.

In another, more sly experiment, Schwarz's team set up a situation whereby half of the subjects would -- by apparent luck -- discover a dime on a photocopy machine before being interviewed. Though the good fortune was meager by most standards, the respondents who stumbled upon it reported significantly higher life satisfaction than those who did not.

These studies corroborate Kahneman's analysis: that people are fickle with their assessments of life satisfaction, basing such evaluations upon their current mood state. With this in mind, let's return to the marriage graph.  

"People who recently married, or are expecting to marry in the near future, are likely to retrieve that fact when asked a general question about their life," Kahneman states. Since marriage -- by and large -- is viewed as a great boon, they will probably deem their lives more satisfying.

So, concludes Kahneman, "Figure 16 can be read as a graph of the likelihood that people will think of their recent or forthcoming marriage when asked about their life."

Hurray! Marriage is vindicated of causing abject misery!  

In the opening scenes of Star Trek II: The Wrath of Khan, two Starfleet officers find themselves in quite a perilous situation. Captured by a group of renegades bent on revenge against Captain James T. Kirk, the duo is forced to host slimy, grotesque parasitic worms that crawl into their ears and roost in their brains. There, the parasites exert control over the two officers, bending their minds to the will of the renegades.

To the best of our knowledge, insidious parasites like these only exist in science fiction. However, there is an organism on Earth -- a single-celled protozoan to be specific -- that bears a striking resemblance. And alarmingly, it may infest as much as a third of humanity (including 45% of the French)!

That parasite is Toxoplasma gondii. Commonly found in domestic cats, it sexually reproduces only within feline intestines. Humans can contract the parasite by ingesting anything contaminated with cat feces. Once infected, individuals may succumb to mild, flu-like symptoms for a couple weeks, but little more. Often no symptoms manifest at all. The parasite's apparent harmless nature cloaks its presence. Soon after finding its way into a human host, it weasels its way into the brain. There, "sheltered from the full fury of the immune system," it can remain in what's called a tissue cyst for decades, not reproducing, just persisting. But in this form, researchers are finding that it can produce some subtle and startling changes in the host's behavior.

Biologist Jaroslav Flegr, one of the leading researchers on T. gondii has discerned some very peculiar findings when comparing people with the infection to those without it. Kathleen Mcauliffe reported on this last year in The Atlantic:

...males who had the parasite were more introverted, suspicious, oblivious to other people's opinions of them, and inclined to disregard rules. Infected women, on the other hand, presented in exactly the opposite way: they were more outgoing, trusting, image-conscious, and rule-abiding than uninfected women.

Additionally, people infected with T. gondii display slightly impaired motor skills, undertake more risks, and get into more automotive accidents. Furthermore, 38 studies have linked the parasite with schizophrenia, a fact which fascinates neurologist and Yale assistant professor Steven Novella.

"Some drugs which are typically used to treat schizophrenia actually have anti-toxo effects," Novella said on a recent episode of The Skeptic's Guide to the Universe. "So they may work because they're actually counteracting toxoplasma, itself."

How T. gondii subtly reprograms the brain is still not well understood. Studying the parasite outside of the body, researchers have found that it profoundly affects gene expression in host cells, as well as molecules involved in signal transduction pathways. If neurons in the brain are influenced in the same manner, that could possibly give rise to the behavior-altering effects.

Worldwide, as many as 1 in 3 people have T. gondii in their brains. Scary, I know. But hold off on any urges to cull the cat population. Indoor cats pose little to no threat to their owners, and the prevalence of infection is only about 1 in 10 in the United States (and currently declining). However, that's still a significant amount, a preponderance that makes you wonder how much of an effect these microscopic, mind-altering parasites really have on human interactions and everyday life as we know it.

(Image: Toxoplasmosis via Shutterstock)

To juniors and seniors at the University of Wisconsin - Madison planning on medical school, introductory physics is far more menacing than its "introductory" title might connote. For many of these students, this is one of the cardinal obstacles in their quest to one day become obstetricians, radiologists, or brain surgeons. The barrier is two-pronged: Medical schools demand near-perfect grades, and students sport a common belief that physics doesn't apply to their chosen path. Agonizing pressure is placed on students to excel at a class they don't really care about.

Since 1930, prospective doctors have been required to undergo a heavy load of science courses: biology, chemistry, the ever daunting organic chemistry, and, of course, physics. In the early years, this stipulation was scrutinized, and 80 years later, the critiques haven't alleviated, they've only become more refined. David Muller, the Dean for Medical Education at the prestigious Mount Sinai School of Medicine in New York City, summed up these arguments recently in the New England Journal of Medicine:

Critics argue that the pace of scientific discovery and its clinical application have outstripped the requirements; that information technology has made memorizing vast amounts of content unnecessary; that the requirements lack clinical, scientific, and social relevance; that they're used to cull the herd of talented aspiring physicians; that they disadvantage minority and female students; that they crowd out studies of bioethics, social justice, and health policy; and that rigidly structured premedical and medical school curricula hinder students from becoming self-directed lifelong learners.

To a degree, Muller agrees with many of these contentions. That's why Mount Sinai has, since 1987, been testing an alternative pre-med education route. Under the college's Humanities and Medicine Program (HuMed), students majoring in the social sciences and humanities are admitted to medical school without taking most of the typical "hard science" classes. Instead, they only take basic biology and chemistry and undergo an eight-week boot camp that, according to Muller, "exposes them to clinically relevant organic chemistry, physics, and clinical rotations." Most importantly, HuMed students are exempted from the dreaded Medical College Admission Test (MCAT).

Since its inception, researchers have been closely monitoring the HuMed program. They've found that the enrolled students are generally just as successful in medical school as their peers.

"There were no differences in the proportion who failed courses, were required to repeat a year of medical school, or withdrew or were dismissed from medical school," Muller wrote of the analyses.

Owing to the program's preliminarily favorable results, Mount Sinai is ramping up and expanding HuMed in the fall, albeit with slightly more stringent requirements. These involve more "hard science" classes, including one semester of basic physics, although with laxer grade requirements than what's traditionally demanded. 

These additions might be a downer to prospective medical students, including one 2010 HuMed entrant who told the New York Times that physics was a "waste," but it's probably a wise course of action.

After all, physics underpins a great many of medicine's current and future practices and technologies, like X-rays, radiotherapy, and minimal-access surgery. A 2012 editorial from the Institute of Physics argued that "medicine is likely to become an information science, where a vast amount of complex data are analyzed by techniques such as machine learning to discover patterns and principles." If there's one thing that physics teaches well, it's how to be detail-oriented.

But physics is beneficial to doctors at an even more basic level. As one enlightened Internet commenter mused, understanding heat transfer comes in handy for dealing with frostbite, hypothermia, and fevers. Simple mechanics elucidates the motion of joints. Fluid dynamics is vital for understanding the circulatory system.

Most importantly, physics and other hard sciences rigorously train students in the scientific method, which is foundational to modern medicine.

Yes, to the prospective medical student, physics class is a solid barrier. But if they pay attention, they just might realize the force that will smash that barrier to bits.

(Image: Doctor via Shutterstock)

Heterosexual men mentally melt in the presence of attractive women. As Tom Jacobs writes in Pacific Standard, even the very thought of possibly interacting with a woman is enough to "temporarily impede men's mental abilities."

Of course, women know this, and some use it to their advantage. (Companies also know this, and they use it to their advantage, too: During my years in graduate school, many of the biotech sales reps were unusually attractive women.) Men feel more trusting toward women who cause them to be sexually aroused, even if there is no good justification for it -- just like when Indiana Jones totally fell for that sexy Nazi chick in Indiana Jones and the Last Crusade.

Is there a way for men to avoid these devilish "honey traps"? (It's unknown if the "honey trap" is named after CNBC's anchor formerly known as the "Money Honey.")

Yes. They can take an antibiotic.

Minocycline is typically used to treat acne, but it can also reduce symptoms associated with mental illnesses, such as schizophrenia and depression, and it can improve decision-making. This latter effect was analyzed further in a study described in Scientific Reports.

Japanese researchers recruited about 100 men to play a trust game using photographs of women. In the game, each man was given 1300 Yen (approx. $13) and asked to rate the attractiveness of each woman as well as how much money they would give them in the trust game. The men were told that the amount of money given would be tripled, and the woman could then choose how to split the money between herself and the man. Unbeknownst to the men, every woman had already chosen in advance to take all of the money, completely stiffing the man. In other words, every woman was a potential "honey trap."

Prior to the experiment, the men were given either placebo or minocycline. The men who took minocycline were immune to the seductive allure of the honey traps. (See graph.)

As shown, men who were taking placebo offered about 50% of their money in the trust game to women of "low attractiveness," while they gave 65% of their money to women of "high attractiveness." Men receiving a regimen of minocycline gave about 50% to both groups of women.

Let this be a lesson for all male businessmen: When engaged in negotiations with an attractive female, be sure to have a doctor's prescription handy.

Source:  Motoki Watabe, Takahiro A. Kato, Sho Tsuboi, Katsuhiko Ishikawa, Kazuhide Hashiya, Akira Monji, Hideo Utsumi & Shigenobu Kanba. "Minocycline, a microglial inhibitor, reduces 'honey trap' risk in human economic exchange." Scientific Reports 3, Article #: 1685. 18-Apr-2013. doi:10.1038/srep01685

As a graduate student in the early 1990s, ornithologist Jack Dumbacher performed the almost obligatory trek to New Guinea to study the island's legendary birds-of-paradise. It was there, in the country's lush, dense rainforest that he unwittingly discovered the world's first known poisonous bird.

Dumbacher and his compatriots had placed mist nets up in the forest in order to capture and study the native flying fauna. One day, extracting birds from these nets, he was handling a number of hooded pitohuis, songbirds with black and orange plumage. Frazzled by their temporary captivity, the birds bit and scratched wildly as they were being released from their tethered confines.

"The cuts really stung, but we had so many nets to [deal with] we didn't have time to stop and put band-aids on our cuts," Dumbacher recalled, "so we popped our fingers in our mouth and ran off to the next net."

But the researchers quickly started to feel funny.

"Our mouths began to tingle, burn, and even go numb. The sensation lasted for several hours," Dumbacher remembered.

Dumbacher and his colleagues had inadvertently ingested a pernicious neurotoxin called batrachotoxin. When consumed, the toxin adversely interacts with nerve cells by keeping their voltage-gated sodium channels open. This means that muscle and brain cells can't generate an ion potential and fire like they're supposed to. In low doses, the toxin merely renders nerves and muscles inoperable, but in higher doses, it can actually cause paralysis and inhibit one's ability to breathe, potentially resulting in death.

But where did such a perilous toxin come from? Dumbacher had a theory, and after querying the indigenous people, his suspicions were confirmed: It was those darn pitohuis!

It wasn't until 2004 that Dumbacher, now a curator at the California Academy of Sciences, would discern how the pitohuis acquired their toxicity. As it turned out, the birds imbibe batrachotoxin from consuming a certain type of beetle. The birds are naturally resistant to the toxin, and as it accumulates in their bodies, it suffuses throughout their skin and feathers. Simple touch can transmit the possibly fatal poison.

Make no mistake, pitohuis aren't birds you want for pets. They may, however, have potential as cloak-and-dagger murder weapons in a television crime drama.

(Image: Hooded Pitohui by markaharper1 via Wikimedia Commons)

"That was a bad mistake because I've got a degree in physics. I used the thermodynamic laws of physics; I put in my body weight and my humidity and so on. I assumed the furnace to be at 5,000 degrees and I will last for just on 2.1 seconds. It's hardly eternity."

I adore this comment for more than just its science underpinnings. Williamson figuratively points out that illogical, over-the-top threats and arguments don't hold weight in the midst of logic and reason, which -- by the way -- should always reign in politics.

Now, gay marriage is notoriously difficult to study scientifically, but I think it's safe to say that allowing devoted homosexual couples to express their love through marriage will not destroy morality or end society as we know it. Even the most plausible argument against gay marriage -- that such an institution would somehow harm children -- is lacking in evidence.

Rational thought, abetted by science, makes for sound policy-making. Maurice Williamson and the New Zealand Parliament demonstrated this last week. Washington, D.C. should take note.

(Congress should also learn to have a sense of humor. Our proceedings seem positively stodgy in comparison to New Zealand's!)

It's amusing and intellectually stimulating to seriously ponder the existence and characteristics of alien life. But like quantum mechanics, such contemplations can easily wrack the mind, leaving one quite discombobulated. I can only imagine the self-inflicted vexations suffered by astrobiologists, whose livelihoods require daily ruminations about life on inconceivably faraway worlds.

After all, the vast randomness inherent to the evolutionary process can give rise to creatures the likes of which we cannot fathom. You've undoubtedly heard the maxim "Life finds a way." Well, if life has indeed found a way on one of the other trillions of planets in our Milky Way Galaxy, it would likely not be our way.

So what would life resemble instead?

My favorite answer to that question originated from the 1976 paper "Particles, Environments, and Possible Ecologies in the Jovian Atmosphere," penned by astrophysicists Carl Sagan and E. E. Salpeter. With learned speculation and fascinating imagination, they envisioned what life could be like on a planet like Jupiter. If such a planet were hospitable to life, the native fauna and flora wouldn't be anything like that on Earth.

In the dense clouds, rich in hydrogen and helium with traces of ammonia, methane, and water, tiny floating organisms could suddenly spring up, jolted into existence by electrical discharges more than 1,000 times as powerful as lightning here on Earth. These creatures could be photosynthetic autotrophs, gaining energy from sunlight and making their own food. Or they might very well be heterotrophs, feasting on organic molecules like ethane and methane. In their paper, Sagan and Salpeter called these organisms "sinkers."

Over many thousands of years, these sinkers could evolve or coalesce into new life forms: "floaters." Resembling gigantic jellyfish, these immense "living balloons" might be the size of small cities. They could stay buoyant by pumping heavy gasses from their interiors or by keeping their hydrogen-filled insides warm. Through their amazingly thin skin, floaters might absorb and feast on the much tinier sinkers.

Salpeter and Sagan conceived of these floaters "arrayed in great, lazy herds as far as the eye can see, concentrated in the updrafts in the enormous sea of clouds."

The two astrophysicists also dreamed of another life form: "hunters." Winged, faster, and more maneuverable, they would nip and peck at the much larger floaters to sustain themselves.

In the 37 years since Sagan and Salpeter envisaged sinkers, floaters, and hunters, we've learned much about Jupiter. We now know that these life forms do not exist, at least in our solar system. Jupiter's atmosphere may simply be far too turbulent and hostile. Or perhaps life never received the improbable, yet necessary spark.

But the nonexistence of sinkers, floaters, and hunters has not dimmed the search for life in our stellar neighborhood. In fact, Jupiter's moon Europa is one of the likeliest candidates to harbor life. At the bottom of the moon's ice-covered ocean, microbes might very well persist among hydrothermal vents, using a process called chemosynthesis to convert inorganic molecules into usable nourishment.

Imagine if -- one day -- we found something; even just a speck! In the landmark television series Cosmos, Carl Sagan asserted that such a discovery would "deprovincialize biology."

"It will show us what else is possible."

(Images: 1. Structures on ALH84001 meteorite by NASA via Wikimedia Commons 2. Hunters & Floaters via Carl Sagan's Cosmos)