Dance Your Ph.D.

I've been researching smell, and stumbled upon this riotously entertaining dance video. Really. You'll have to trust me on this one.

Dance your PhD 2011



"Smell mediated response to relatedness of potential mates. Individuals often migrate from their place of origin in a relatively slow pace. As such, related individuals frequently interact. Relatedness between two individuals is defined as the percentage of genes in those two individuals that are identical by..."

In Discover Magazine This Month: Lawnmower Man

It was Mary Leakey who discovered Paranthropus boisei, an evolutionary cousin of ours that went extinct some 1.5 million years ago. Because of his strong jaws and facial musculature, he has long been called Nutcracker Man. New research shows he was a grazer. See Discover Magazine's "Top 100 Stories of 2011 #85: Meet the Grazing Hominid."


It's Not Just Narcissists Who Want Plastic Surgery....

It's narcissists who are perfectionists.

Call it their own Snopes.com sleuthing. But hearing again and again that narcissistic self-absorption and perfectionistic striving fuel the current boom in cosmetic surgery, researchers at Canada's Dalhousie University decided to poke around a bit in the assumptions. To do so, they recruited 305 undergraduate women, and had each one complete tried-and-true diagnostic questionnaires returning measures of narcissism and perfectionism, along with one measuring interest in cosmetic surgery.

The researchers discovered that neither narcissism nor perfectionism predicted interest in cosmetic surgery. However, women scoring high on measures for both diagnoses showed the strongest interest in cosmetic surgery of any women in the study.

The implications of this study may be profound--for plastic surgeons. In the June 2011 issuse of Plastic and Reconstruction Surgery: The Journal of the American Society of Plastic Surgeons, the authors speculate that cosmetic surgeons' patients may be grandiose and demanding to a fault--and, by diagnosis, "nearly impossible to satisfy," no matter how objectively successful their cosmetic surgery was.

Next up: How would 305 cosmetic surgeons perform on measures of depression, anger, and desire for a new career?

Because Mom Likes Valentine's Day and Hates Halloween

A hugely pregnant woman and her OBGYN walk into a bar. The woman says, "When will this baby ever come?" And the OBGYN says, ....

It's a joke waiting for a punchline--that's been delivered (ba-da-bum) in the October 2011 issue of Social Science and Medicine. And here's the punchline: The baby's arrival may be either delayed or hurried along by Mom's emotions.

Researchers at the Yale University School of Medicine's School of Public Health analyzed birth certificate information for all births in the United States for the weeks before and after Valentine's Day and Halloween across 11 years. They determined that on Valentine's Day there was a 3.6% increase in spontaneous births and a 12.1% increase in cesarean births. On Halloween, however, there was a 5.3% decrease in spontaneous births and a 16.9% decrease in cesarean births.

In Discover Magazine This Month: Man's Best Friends Know Who Their Best Frieinds Are

Dogs Can Help Themselves by Deciphering Human Interactions

In October's Discover Magazine:

Researchers and pet owners have long known that dogs can learn spoken commands and understand certain human gestures. But can they actually eavesdrop—that is, pick up information simply by watching interactions between people? Animal cognition researcher Sarah Marshall-Pescini and her colleagues at the University of Milan believe that dogs do indeed engage in interspecies snooping....

Read the article.

In Discover Magazine This Month: The Wine Whisperers

What does California taste like--in a wine? And who are the artisans who can bring that to [groan] fruition? See my Destination Science piece in September's Discover Magazine: "The Wine Whisperers."

ET, Go Home

What If We Call Out to Extraterrestrials, and They Respond?

NASA routinely beams messages into the universe in an attempt to contact extraterrestrial intelligence. In more than 50 years of listening for a response, they've heard zilch. Which might be good. For even as NASA sends messages, some of its scientists wonder what it is they should say, and whether Earth should, indeed, keep putting out the proverbial welcome mat.

In "Would Contact with Extraterrestrials Benefit or Harm Humanity?", in the June/July 2011 issue of Acta Astronautica, researchers from the University of Pennsylvania's Departments of Geography and Meteorology, and from NASA, systematically analyze a broad range of contact scenarios, categorizing each one as beneficial, neutral, or harmful to humanity. Although the researchers do not perform quantitative analysis on the likelihood of the various scenarios, they do note that a relatively large number fall into the "harmful" category. Because of this, they recommend that Earth's messages to extraterrestrials be written more cautiously.

For example, we should stop sending "About Us" information that includes specifics about our DNA. (It could be used to design biological weapons against us.) Initial communication should be limited to mathematical discourse, and we should take care not to suggest that we want to colonize other planets. Nor should we broadcast that we are less than admirable stewards of the natural resources of our own planet. After all, we want to seem like the sort of neighbors a more advanced civilization would want to keep around.

Praying for Peace

Religion may have caused century upon century of war, but praying--well, that's something we should all get behind. So say researchers from the University of Michigan in Ann Arbor and from VU University in Amsterdam in "Pray for Those Who Mistreat You: Effects of Prayer on Anger and Aggression" (Personality and Social Psychology Bulletin, March 18, 2011). In three control-group experiments the researchers determined that the act of praying for strangers who had provoked them actually calmed subjects' anger and aggression--and it did so with almost miraculous speed. If religion is the opiate of the masses, what's praying? Maybe the valium of the oppressed.

In Discover Magazine This Month: 20 Things You Didn't Know about Magnetism

In the July-August special issue of Discover Magazine:

1 Magnetism is familiar to every fifth grader, but describing it can confound even the most brilliant physicist.

2 Take the case of Richard Feynman. When asked to explain magnetism, he urged his BBC interviewer to take it on faith (video). After seven minutes of stonewalling, he finally said, “I really can’t do a good job, any job, of explaining magnetic force in terms of something else that you’re more familiar with because I don’t understand it in terms of anything else that you’re more familiar with.”

3 He did break down and try for a few seconds before abandoning the attempt. Those seconds were packed with oversimplifications: “All the electrons [in a magnet] are spinning in the same direction.”

See "things" 4-20.

Clowning and IVF Success Rates

Anticipating a Sudden Run on Red Rubber Noses

Though it's been tried for millennia, it is of course as yet unproven that crying works as birth control. But laughing may help fertility. In a quasi-randomized study, researchers at Assaf Harofeh Medical Center in Zrifin, Israel found that the pregnancy rate following in vitro fertlization and embryo transfer was more than 16% higher among women who were visited immediately after embryonic transfer by a medical clown. As reported in "The Effect of Medical Clowning on Pregnancy Rates after In Vitro Fertilization and Embryo Transfer (IVF-ET)" (which came online in January in the journal Fertility and Sterility) the clown performed 12-15 minute routines of jokes, tricks, and magic at each woman's bedside. The researchers point out that the immune benefits of humor have long been understood, and that the beneficial effect of stress reduction on successful egg implantation has been demonstrated recently in rats. They also suggest that, even though their method requires one clown per IVF mom, it's a cheaper and more successful intervention than many other stress reduction techniques that fertility clinics have historically advocated.

Facebook Me. No, Me! No, Me!

You might think that narcissists' Facebook profiles would be heavily spiced with the word "I." But it seems that even narcissists know that's a dead giveaway about their least attractive personality trait. In "Narcissism and Implicit Attention Seeking: Evidence from Linguistic Analyses of Social Networking and Online Presentation" (July 2011 in Personality and Individual Differences), an international team of researchers report on a typical social networking "workaround" used by narcissists. When they restrain their online use of the word "I," they call attention to themselves with sexy photos and profanity.

In Scientific American This Month: Beauty and the Beasts

In July's Scientific American:


Show a man a picture of an attractive woman, and he might play riskier blackjack. With a real-life pretty woman watching, he might cross traffic against a red light. Such exhibitions of agility and bravado are the behavioral equivalent in humans of physical attributes such as antlers and horns in animals. “Mate with me,” they signal to women. “I can brave danger to defend you and the children.” ....

Read the article.

Conspiracy Theories and Paranoia

So ... um ... how do you think Princess Diana died? JFK? When you talk about the "terrorist attacks of 9/11," do you actually draw air quotes with your fingers? Was coverage of the U. S. Apollo missions to the moon a sham? Is your government hiding visits from space aliens?

A long-growing body of research suggests that people who believe in conspiracy theories do so in order to vent unrelieved negative and angry feelings. These people are disagreeable and have difficulties in their relationships with authority figures. This body of research has now been topped off by a study conducted at Northumbria University in Newcastle. In "Belief in Conspiracy Theories. The Role of Paranormal Belief, Paranoid Ideation, and Schizotypy," in the June 2011 Personality and Individual Differences, the psychologists report that people who believe in conspiracy theories score high on measures of paranoia and schizotypal (odd loner) behavior. The psychologists suggest that, for many such people, conspiracy theories may serve a useful function, giving them a safe hook on which to hang their otherwise mounting anxiety.

In Discover Magazine This Month: 20 Things You Didn't Know about Stress

In June's Discover Magazine:

1 Think about money, work, economic outlook, family, and relationships. Feeling anxious? In a 2010 American Psychological Association survey [pdf], those five factors were the most often cited sources of stress for Americans.

2 Stress is strongly tied to cardiac disease, hypertension, inflammatory diseases, and compromised immune systems, and possibly to cancer.

3 And stress can literally break your heart. Takotsubo cardiomyopathy, or “broken heart syndrome,” occurs when the bottom of the heart balloons into the shape of a pot (a tako-tsubo) used in Japan to trap octopus. It’s caused when grief or another extreme stressor makes stress hormones flood the heart.

See "things" 4-20.

Pornography Terms in Google Searches by Democrats and Republicans

The "challenge hypothesis" first put forth in 1990 in an article in The American Naturalist states that, as an evolutionary holdover from the need to guard mates and progeny, testosterone levels in males are high after vicious competition. Evidence to support the hypothesis has been found in birds. And in human competitors following various types of sporting competitions, elevated testosterone levels have been found--but only in winners. Even politics can provide a testosterone boost, and not only to the direct competitors. For example, right after the 2008 elections, researchers found higher testosterone levels in men who voted for Barack Obama than in men who voted for John McCain.

Now, demonstrating perhaps that the exquisitely sensitive thumb Google has on the pulse of our nation can serve as an epidemiological assay of biomarkers, researchers from Villanova and Rutgers Universities have been following the search terms used in red and blue states. They report that people in traditionally Republican states conducted Google searches for pornography keywords more often after the 2010 midterm elections (widely seen as a Republic victory) than after the 2008 elections (widely seen as a Democratic victory). On the other hand, people from Democratic states searched for pornography terms less frequently after the 2010 Democratic loss than after the 2006 Democratic win. The study assumes a direct correlation between testosterone levels and interest in pornography. It is "Pornography Seeking Behaviors Following Midterm Political Elections in the United States: A Replication of the Challenge Hypothesis," in the May 2011 issue of Computers in Human Behavior.

In Scientific American This Month: Coral in Love

In May's Scientific American:

It is hard to court the opposite sex when you are cemented in place, which explains why polyps—the tiny creatures whose exoskeletons form corals—do not reproduce by mating. Instead they cast millions of sperm and eggs into the sea, where they drift up to the ocean surface, collide, form larvae and float away to form new coral reefs....

Read article.

In Discover Magazine This Month: 20 Things You Didn't Know about Cyrstals

In May's Discover Magazine:

1 It’s all about the rhythm: Crystals are repeating, three-dimensional arrangements of atoms, ions, or molecules.

2 Almost any solid material can crystallize—even DNA. Chemists from New York University, Purdue University, and the Argonne National Laboratory recently created DNA crystals large enough to see with the naked eye. The work could have applications in nanoelectronics and drug development.

3 One thing that is not a crystal: leaded “crystal” glass, like the vases that so many newlyweds dread. (Glass consists of atoms or molecules all in a jumble, not in the well-patterned order that defines a crystal.)


See "things" 4-20.

Women Think Venus Is Funny; Men Prefer Mars

Gender Differences in How We Process Humor

Functional MRI images have shown gender differences in emotion processing, and behavioral studies have found gender differences in humor processing. In "Gender Differences in the Neural Correlates of Humor Processing: Implications for Different Processing Modes" (in the April issue of Neuropsychologia) an international team of investigators report on an experiment assessing the reactions of 14 females and 15 males to cartoons. Blood oxygenation levels were assessed alongside fMRIs. Women, it seems, process humor primarily in the part of the cortical processing system associated with primitive emotions and motivations. While men, too, engage those deep brain structures, more than women they also engage parts of the cortex associated with evaluative thinking.

Which Came First, the Tool or the Hand Size?

Did Technology Drive Human Evolution?

140 years ago Charles Darwin speculated that tool use may have influenced the evolution of the human hand. Now, in "Technology Based Evolution? A Biometric Test of the Effects of Handsize Versus Tool Form on Efficiency in an Experimental Cutting Task," in-press at the Journal of Archeological Science, two anthropologists at the University of Kent in Canterbury are investigating the particulars of that idea. Through a series of experiments with stone flake tools (similar to the those used by African hominids 2.6 million years ago) and un-handled steel blades, they have shown that bigger hands use those tools more efficiently. The scientists speculate that just as opposable thumbs may have enabled tool use, tool use may have influenced the biological evolution of hand size—and of musculature and bone structure in the hand. As eons ticked on, it was the hominids with genes coding for hands adept at tool use that survived.

In Scientific American This Month: Outsmarting Dengue Fever

In April's Scientific American

Just after sunrise in early January, a delivery van trundled along a suburban street in Queensland, Australia. Inside were tubs filled with a type of mosquito that carries dengue fever, the flu-like illness that annually sickens 50 million to 100 million people worldwide. Workers inside the van stopped at every fourth house, took out what resembled a small Chinese food container and released 40 mosquitoes into the wild. After a week, they had filled the air with 6,000 insects. By early March they had launched 72,000....

Read the article.

Shaky Reasoning

In 2008, the Vermont Yankee nuclear power plant in Vernon, Vermont began storing high-level radioactive waste in 19-foot tall dry casks outdoors, on a concrete slab 254 feet away from the bank of the Connecticut River.

That's a foot and a half beyond what Dr. Leslie Kanat, a Geology Professor at Johnston State College, calls the "Probable Maximum Flood Level."

I am more than a bit concerned about those casks, but maybe I ought to feel relieved--even if a foot and a half doesn't sound like much. Maybe I also ought to feel relieved that Holtec International, the company supplying the casks, reports that their casks stay operational even when submerged at 50 feet for 8 hours. But while Holtec's tests have reassured me that river water would not be a problem for those dry casks, I'm not so sure about river mud.

Holtec's dry casks have vent holes at top and bottom. They are designed for air to enter at bottom, cool the waste, and exit at top.

What would happen if those vents were blocked? Did Holtec run tests for that?

It did not. But in 2002, Dr. Marvin Resnikoff, an international consultant on radioactive waste management, was asked by The Connecticut Yankee Decommissioning Advisory Committee how long it would take for a cask to overheat if vents were blocked. His answer: Maybe a week.

"Maybe." And, again, maybe I should feel relieved. After, all, there's a nice margin of safety in that hypothetical week. I can imagine fire engines arriving at the high-level radioactive waste storage slab right after helping little old ladies out of their collapsed homes, and taking care to hose down the casks after hosing down the fires decimating Main Street. But what about the fact that guesses are sometimes off the mark? What if there were not a week to spare but only two days or three? Would emergency workers even know to abandon their attempts to help survivors and begin to frantically deal with muddy dry casks?

And what about the fact that, during his testimony to the Connecticut Yankee Decommissioning Advisory Committee, Dr. Resnikoff explained that each dry cask contains a Cesium and Strontium inventory equal to 10 Hiroshima bombs?

Entergy, the plant's corporate owner, has never actually acknowledged that mud could reach the vents of the dry casks at Vermont Yankee. Their directors and administrators keep the conversation focused solely on water. But Ray Shadis, technical director for the anti-nuclear watchdog group New England Coalition, is concerned about the combination of Cesium, Strontium, and high temperatures due to a failed, mud-dependent cooling system. In a not-too-difficult-to-imagine scenario, Shadis suggests that the ground surrounding the concrete slab that holds the casks could become wet with river water. Consequently (he says), the slab could become unstable.

And then what?

Well, if you shake even relatively dry soil really, really hard, its strength and stiffness are reduced. That's called "liquefaction." It's responsible for much of the damage during earthquakes. If you actually add liquid to the mix, you create something like quicksand.

What if the Connecticut River Valley suffered a double whammy of flood plus even a minor earthquake? Could the ground around the slab holding the dry casks become like quicksand? Could an edge of the slab shift or, worse, tip?

Even Entergy has suggested that the ground around the concrete slab could get an occasional and maybe even regular soaking soaking from river water. What they haven't gone out of their way to point out is that Vermont is in a bit of an earthquake zone. We have been significantly rattled 15 times since 1900.

Most scientists agree that we are entering an unstable time weather-wise, with melting ice caps, rising waters, and the possibility of more frequent flooding. Given that, I can't help but question Entergy's foresight in trying to get a license extension allowing them to create another 20 years of radioactive waste, only to store it in an earthquake zone near a population center at river's edge.

This is adapted from a Vermont Public Radio commentary by the author.

In Scientific American This Month: Bison vs. Mammoths

In March's Scientific American:

Bear-size beavers, mammoths, horses, camels and saber-toothed cats used to roam North America, but by 11,000 years ago most such large mammals had died off. To this day, experts debate what caused this late Pleistocene extinction: climate change, overhunting by humans, disease—or something else? Eric Scott, curator of paleontology at the San Bernardino County Museum in Redlands, Calif., suggests it was something else: namely, the immigration of bison from Eurasia....

Read the article.

In Discover Magazine This Month: 20 Things You Didn't Know about Spiders

In the March Discover Magazine:

1 The venom of the Australian funnel-web spider can kill a person in less than an hour, and its fangs can bite right through a shoe.

2 But for most people, fear of spiders is a far greater problem than the spiders themselves. Researchers at the University of São Paulo have developed an improbable way to undo arachnophobia by having patients stare at pictures of “spiderlike” objects—a tripod, a carousel, a person with dreadlocks.

3 Quackery? Apparently not. In a 2007 study, the scientists reported a 92 percent success rate.

See "things" 4-20.

Up Malaria's Sleeve

And why bed nets don't quite do the trick

The primary vector of malaria to humans has long been known to be the Anopheles gambiae mosquito. When one bites a human it transmit the parasite Plasmodium falciparum, and that's what hosts the virus. The insects bite mostly when inside human dwellings. Hence, malaria control methods rely heavily on the indoor use of insecticides and on bed nets.

Despite best efforts, however, malaria continues to infect about 250 million people a year and kill about a million. In the February 3 issue of Science a team lead by parasitologist Ken Vernick of the Pasteur Institute in Paris reports the discovery of a subtype of A. gambiae that may account for some of the continuing high rate of infection. Mosquitoes of this subtype--known as Goundry, for the African village in the country of Burkina Faso in which Vernick's team found it--live outdoors, and they seem to be particularly dangerous. Goundry are more susceptible than indoor-living A. gambiae to Plasmodium, acquiring infection 23% more frequently when feeding on malaria-infected blood.

Vernick and colleagues have yet to find adult Goundry in the wild. What they discovered outdoors were larvae, which they hatched in the lab, raised to adulthood, genetically tested, and used in infection experiments. Possibilities for population control of Goundry include traditional methods like wide-spread fogging, and newer, chemical-free approaches like the release into the wild of genetically engineered sterile males.

Sterile insect technology has problems above and beyond push-back from a public afraid of "Jurassic Park" insects. How do you breed a bug to be both sterile and hardy? Sterile and sexy? How do you track the insects? (There are no physiological markers identifying them as sterile.) These are issues pressuring not only scientists who combat disease-carrying mosquitoes but those fighting agricultural pests like fruit flies, coddling moths, and pink bollworms, as well.

The New Madrid Seismic Zone: Much Ado About Something ... Unexpected

In 1811 and 1812, four major earthquakes (M7.4 to M8 on the Richter scale) centered in New Madrid, Missouri changed the course of the Mississippi River near Memphis, and may have caused the river to flow temporarily upstream. The entire fault system has been named after those earthquakes' epicenter. The biggest part of the New Madrid system sits in Missouri; it then extends along the Mississippi River Valley from northeast Arkansas through southeast Missouri and into western Tennessee and western Kentucky. The more than 4,000 earthquakes recorded there since 1974 make it the single most active fault system in the United States.

Is a "big one" centered in New Madrid on the near horizon? Anxiety runs high, and the local data are fearsome.

Yet the New Madrid (pronounced New MAD-rid) seismic zone is a mid-continent, or intraplate fault system, a rift occurring within the interior of a tectonic plate, and that may be key in forecasting the fate of the New Madrid area. Publishing in the journal Lithosphere, Mian Liu, professor of geological sciences at the University of Missouri-Columbia, Seth Stein, professor of earth and planetary sciences at Northwestern University, and Hui Wang, a Chinese Earthquake Administration researcher, suggest that widespread concern about the New Madrid area may be misplaced—literally. Examining about 2,000 years of records of mid-continent earthquakes from China, they found that big earthquakes never struck twice in the same place. Rather, after an initial earthquake, a series of aftershocks quaked the immediate area, sometimes with intensity approximating that of the initial shock. Additional trembling sometimes occurred with astonishing frequency over hundreds of years. The next major earthquake, however, was always further along the fault system. The investigators' GPS data show that an earthquake and prolonged resettling on one spot of a fault system inevitably increases tectonic stress on other sections of the system.

All of which suggests that New Madrid itself will probably not host the next mid-continent big one. On the other hand, St. Louis and Memphis—both of which are heavily populated, and situated near the furthest reaches of the New Madrid fault system—might. It could be what FEMA calls a "maximum of maximums" event. In anticipation of such a catastrophe, FEMA will lead a national-level exercise in May of 2011. Federal, state, and local governments will be involved, as well as businesses, private groups, and even faith-based groups. As May approaches, FEMA will make more exercise information available.

Species Assault is a Go

If it weren't nonfiction, it might be the definitive computer nerd thriller. "The computer says you must now die, and this is how it will happen." Really. And "the state" controls the computer.

But it's not necessarily as Orwellian as it sounds. For it's pest control of the animal variety that's the topic. Australia is spectacularly beset by non-native, invasive species introduced over the years in misbegotten attempts to have exotic pests "bio-control" populations of domestic ones. (One famous example: In 1935 enormous Hawaiian toads were let loose in Australian sugar cane fields to control cane beetles. But as things turned out, the beetles clung near the tops of the stalks, and as high as they jumped, the bottom-heavy toads couldn't reach them. The toads proved to be voracious omnivores. At the same time, they multiplied rapidly and spread diseases among indigenous species.)

Now, according to the first issue of the journal Methods in Ecology and Evolution, a computer application developed by ecologists at the University of Adelaide in Australia offers wildlife managers Spatio-Temporal Animal Reduction (STAR), a spreadsheet of tested culling strategies and options. Cut. Paste. Copy. Move. Deelte. Goodbye feral pigs, buffalo, horses, and other fiendishly foreign fauna. Species assault is a "go."

What Doesn't Kill You Makes You Older

Elizabeth Blackburn of UC San Francisco is part of a three-person team that won the 2009 Nobel Prize in Physiology or Medicine for the 1978 discovery of telomerase, the enzyme that lengthens and stabilizes telomeres. (Telomeres are DNA-protein complexes that cap the ends of chromosomes. As Blackburn explains it, they function like the tips on shoe laces, and protect chromosomes from fraying. However, each time a cell divides, some of the telomeres are used up. Below a critical telomere length, the cell loses its ability to reproduce itself. By replenishing telomeres with each cell division, telomerase plays a critical role in cell health and life span.)

In a landmark study of mothers of chronically ill children that was published in 2004, Blackburn reported that the mothers with the longest-term stress (the mothers with the oldest chronically ill children) had chromosomes with the shortest telomere tips. She and fellow researchers attributed the shorter lengths to diminished serum levels of telomerase, and estimated that during their years of stress those mothers' white blood cells had prematurely aged by 9-17 years.

Now Blackburn is suggesting that the aging news is not all bad for the chronically stressed, for with knowledge comes power. In studies published in 2009 and 2010, some subjects studied actually enjoyed increased telomere length over time. These findings opened the door to the search for factors that can help people lengthen telomoeres. Studies published in 2010 pointed to meditation, exercise, and, for women, delayed menopause.

According to Blackburn, the take-home message for chronically-stressed people who don't want to prematurely fall prey to age-related illness and debility is this: "Work hard. Play harder."

Diamonds Are Forever. Extinction Isn't.

In Australia, researchers at the University of Queensland have compiled a global database on mammals identified as "missing" (a category to which they assign extinct species as well as those "critically endangered and possibly extinct"). The database includes records dating as far back as 1500. In the September 2010 issue of Journal Proceedings of the Royal Society B, mammal ecologist Diana Fisher and statistical ecologist Simon Blomberg report that of the 187 missing species, 67 have been rediscovered. Based on their analysis of factors like date of last sighting and probable cause of extinction, they offer advice for conservationists. Mammals that are wide-ranging, have been missing for not more than 100 years, and are believed to have been killed off by habitat loss are most likely to be recovered; those killed off by predators, disease, or hunting are least likely. Unfortunately that second group includes charismatic mammals like the Tasmanian tiger, for which 25 major searches and countless amateur hunts have been launched. Those bad-bet expeditions happen at the expense of better-bet efforts to save non-celebrity species like the Australian lesser stick-nest rat, thought to have met its end through habitat loss. The researchers advise conservationists to check their data, not their hearts, and apportion their resources to species with a reasonable chances of recovery.

Living Paintings

Jack Pettigrew of the University of Queensland and his research team may have discovered why vibrant rock paintings from the Bradshaw rock artworks in western Australia's Kimberly region have not lost their visual intensity in the 40,000-70,000 years since they were painted. According to a a new study published in the journal Antiquity, the paint is long gone; the figures of humans and megafauna depicted are colored by a biofilm of microbes that are direct descendants of microbes that infected the original paint. The microbes in question are predominantly a black fungi, Chaetothyriales, which replicates by cannibilizing its predecessors, and a reddish organism that seems to be a cyanobacteria. Cyanobacteria obtain energy through photosynthesis. Pettigrew speculates that both the fungi and bacteria were in the original paint in the Bradshaws, and that over tens of thousands of years the fungi has provided water to the bacteria and the bacteria in turn has given carbohydrates to the fungi.

Got Milk?

Mare's milk, all the rave 5000 years ago, is back in fashion. * Cleopatra may have bathed in ass's milk when horse's milk would have done just fine. * Milk lovers may live longer. * Adding milk to black tea wrecks its health benefits. * Failure to-date: trying to turn grass into milk without use of a cow. * Giving a cow a name may boost her milk production. * Breast milk ice cream, anyone? * A mother's laughter may improve the health benefits of her breast milk. * A laser-assisted robot milkmaid in Sweden milks cows anytime they want, and they want it a lot. * Tit birds like milk (but we should have known that). * Breast milk should be drunk at the same time of day that it is expressed. * Space Yoghurt.