Heather Steingruebl is a BABloggee. She contacted me and told me some chilling news: her daughter Elise was recently diagnosed with leukemia. She’s being treated, and I know we all hope things go well for her.

But in the meantime, this makes Elise susceptible to many preventable diseases. We need people to get vaccinated! As Heather says,

Vaccinate. Elise and thousands of kids like her are counting on not dying from things like measles and whooping cough while they fight cancer. Unless it’s a specific health risk to you or your child, just vaccinate. Please.

She also implores people to get on the bone marrow donation registry. Search around online for information on how to do this. I plan on doing this myself.

My heart goes out to her and her family, as it does to anyone affected by this awful illness. I’m going to find out what booster shots I need, because I take this issue very seriously. I hope you do too.

For the tiny flatworm, regeneration of missing body parts is a piece of cake. Someone chopped its head off? No problem! It grows a brand new one in about seven days, complete with a spanking new brain with all the right circuits and connections. (As for the chopped-off head, it just grows a new body.) This amazing ability of the flatworm to regrow a missing head and to produce a brain on demand has now been traced back to a key gene, researchers report in a PloS Genetics study. The identification of the gene is exciting news for scientists who wonder if humans, too, can one day learn to regenerate missing body parts. The Register reports that the discovery of the "smed-prep" gene unlocks the mechanisms by which the hard-to-kill Planarian flatworms grow new muscle, gut, and brain cells:
Even more importantly, it seems that the information contained in smed-prep also makes the new cells appear in the right place and organize themselves into working structures – as opposed to nonfunctional blobs of protoplasm.
Lead researcher Aziz Aboobaker describes the worm's regenerative superpowers to the BBC:
"One of the reasons they can do this is because they're chock-full of stem cells. We estimate that at ...

Flight and fluid dynamics scientist Adrian Thomas of the The Oxford Animal Flight Group made this motion study of a tethered desert locust. As it turns out, the gorgeous look of this video is dictated by the constraints of shooting insects and smoke currents. The black and white makes it easier to shoot, by providing more flexibility with two additional F-stops, and reducing the elements to their most basic parts. Thomas used high-speed video, shooting at 1000 frames per second in order to catch the 20-per-second wing beats of the locust, blasting it all with five kilowatts of light to bring out the smoke. Using another neat trick, the smoke is created by heating baby oil. The desert locust is a good subject because it tolerates the heat and light and is likely to behave normally in these conditions.

These careful studies of insect flight dynamics have yielded significant results. Thomas: “The major obstacle to small micro-air-vehicles is power efficiency. The power density of current battery technologies is not sufficient to allow current flapping micro-air-vehicles to fly for long enough periods to be effective. The careful design of insect wings is one of the features that allows insects smaller than current micro-air-vehicles to achieve migratory flights taking many days and crossing continents.”

Video and still image courtesy Adrian Thomas, Animal Flight Group, Oxford University

Scientists have long suspected that a link exists between mood and chocolate, as studies (done primarily with women) have suggested that eating a chocolate bar temporarily banished the blues. Now a study has brought new complexity to the issue with its finding that depressed people consume larger amounts of chocolate. But researchers are no closer to figuring out which factor is the cause and which is the effect: Do glum people reach for a Hershey bar to lift their spirits, or is the chocolate actually bringing them down?

For this study, researchers at the University of California studied 931 men and women who weren’t on antidepressants and quizzed them on their chocolate-chomping habits. Then, using a standard screening survey, they assessed the volunteers for symptoms of depression. The scientists found that those who were the most blue consumed the most chocolate.

This held true for both the men and the women; people who were depressed ate an average of 8.4 servings of chocolate per month, compared with 5.4 servings among those who were not depressed [Reuters]. Those who scored highest on the mood tests, indicating possible major depression, consumed an average of 11.8 servings per month [Los Angeles Times]. The findings led the research team to conclude in the Archives of Internal Medicine that “depressed mood was significantly related to higher chocolate consumption.”

While the study established a link between chocolate eating and depression, the researchers could not pin down how the two things are related. The authors suggest that depression might stimulate chocolate cravings, and that people might reach for a candy bar to self-medicate; chocolate prompts the release of certain chemicals in the brain, such as dopamine, that produce feelings of pleasure [Los Angeles Times]. But it’s also possible chocolate only provides a short-term lift, and that over time, it contributes to depression. Yet another possibility is that a separate physiological mechanism, like stress, is responsible for both depression and an appetite for chocolate. With this cloud of uncertainty hovering over the candy isle, chocoholics will be eagerly awaiting further studies.

Related Content:
80beats: The First Chocoholics: Native Americans Imported Cacao From 1,200 Miles Away
80beats: Rats Fed on Bacon, Cheesecake, and Ding-Dongs Become Addicted to Junk Food
80beats: Are Women’s Brains Hard-Wired to Have Trouble Resisting Temptation?
80beats: For Obese Women, a Milkshake Brings Less Pleasure to the Brain

Image: iStockphoto

If you thought a cow was good only for its milk and meat, then we'd have you know that somewhere between Oklahoma City and Fort Worth, Texas, there is an Amtrak train chugging along on moo-power. Amtrak is currently running its Heartland Flyer train on a mix of traditional diesel fuel and biodiesel produced from cow products, in an experiment that Amtrak argues could make railroads more eco-friendly. The Heartland Flyer uses about 100,000 gallons of diesel fuel each year to move 84,000 people. For this one-year test run, Amtrak will replace 20 percent of that fuel with biodiesel, produced from tallow from Texas cows. The fat from the cattle, which is normally used to make animal feed and soap, will now instead help power a train. According to Fast Company:
Amtrak says that the cow tallow (read: rendered fat from cattle) fuel reduces hydrocarbon and carbon monoxide emissions by 10%, cuts down on particulates by 15%, and reduces sulfates by 20% compared to standard diesel.
But if the idea of whizzing across the heartland in a cow-powered train makes you uneasy, then you're not alone. The animal rights organization PETA isn't too hot on the idea either, with PETA spokesman Bruce Friedrich telling Fast ...

Four decades ago, the Soviet Union put a reflector on the moon able to bounce laser signals back to the Earth. There was just one problem: They lost it.

But now the marooned reflector has been found, thanks to the determined hunting of University of California, San Diego researchers. NASA’s Lunar Reconnaissance Orbiter, in orbit around the moon, photographed the landing area where the USSR’s Luna 17 mission dropped off the missing reflector, Lunokhod 1, in 1970. The photos turned up a faint reflective dot, and the team thought that was it.

With an idea now where to point their own laser, the researchers received a stronger signal back from Lunokhod 1 than they ever had in years of studying its sister craft, Lunokhod 2. “The best signal we’ve seen from Lunokhod 2 in several years of effort is 750 return photons, but we got about 2,000 photons from Lunokhod 1 on our first try,” said Murphy. “It’s got a lot to say after almost 40 years of silence” [UPI].

After landing near the Mare Imbrium, Lunokhod 1 stayed in touch with Soviet ground controllers for no less than 11 months, prowling the moon even as the US astronauts of Apollo 14 and 15 were driving about elsewhere in their manned moon buggies. However the robot crawler eventually ceased communications, and the project was officially terminated on October 4, 1971 [The Register]. The Soviet scientists lost the location of the reflector, and because it doesn’t reflect enough light from the sun for us to see it from Earth, they never found it again. Firing the laser to look for a signal only works if you know the reflector’s general location, and thus wasn’t possible until the LRO spotted Lunokhod 1 this year.

The American team had used Lunokhod 2 along with three reflectors left behind by Apollo missions to keeps tabs on our natural satellite and track its position and orbit as it ever-so-slowly moves away from us. And the researchers say that the re-discovered Russian reflector is particularly useful for studying the moon’s liquid core and testing ideas about gravity [Scientific American].

Related Content:
DISCOVER: The Bloc on the Block, old Soviet space gear for sale
DISCOVER: The Moon Makes a Splash
Bad Astronomy: NASA Spies on USSR Hardware
Bad Astronomy: Apollo Landing Sites Imaged by LRO!
Bad Astronomy: LRO First Light Images of the Moon!

Image: NASA

If you thought the toxic bubbling lakes of asphalt DISCOVER covered on Friday were impressive, you ought to see what’s under the sea just off the California coast: giant volcanoes made from the same stuff we use to pave our roads.

Lead author David Valentine and his colleagues first found these asphalt volcanoes in 2007 when they sent submersible robots to explore peculiar formations 700 feet below the surface. Now, in a study in Nature Geoscience, the team has published its findings and its images of the extinct volcanoes. Valentine says the formations are six stories high, and spread out farther than a football field. “If I could convert all the asphalt in the largest volcano to gasoline, it would be enough to fuel my Honda Civic for about half a billion miles” [National Geographic], he says.

Valentine first used the aquatic robot Alvin to explore the volcanoes and take samples; the robot’s operators describe the experience as like driving a flat road and suddenly seeing an enormous mountain rise up in front of you. The researchers then deployed the autonomous bot Sentry. “When you ‘fly’ Sentry over the seafloor, you can see all of the cracking of the asphalt and flow features,” Valentine said. “All the textures are visible of a once-flowing liquid that has solidified in place” [LiveScience].

These huge mounds formed 31,000 to 44,000 years ago as petroleum oozed out from the seafloor, the team’s chemical analysis suggests. Over time, the petroleum mixed with sand and debris and hardened into domes. There are also depressions around the largest volcanoes that used to be massive vents of methane, the scientists say. They argue that those vents could have contributed to a spike in the level of methane in the ocean about 35,000 years ago, which researchers knew about before this find.

If indeed the volcanoes once blasted huge amounts of methane into the sea, then the plethora of methane-eating bacteria, combined with the oil reaching the surface and creating slicks, could have created a dead zone for most life. But that was then. Now, with the methane emissions reduced to a few tiny vents, oceanographer Ian MacDonald says that could be turned on its head: These unusual formations could present an opportunity for marine organisms to thrive. “I think it’s really cool that there’s this other process that we didn’t really know about before that, at least in some places, is making pretty extensive hard bottoms for animals to colonize” [National Geographic].

And while the nation’s oil and ocean focus is set on the Deepwater Horizon disaster in the Gulf of Mexico, coauthor Chris Reddy said in a statement that the asphalt volcanoes are a reminder not to forget the natural part of the equation. “The volcanoes underscore a little-known fact: Half the oil that enters the coastal environment is from natural oil seeps like the ones off the coast of California.”

Related Content:
80beats: Do Asphalt-Loving Microbes Point the Way to Life on Titan?
80beats: Sunken Oil Rig Now Leaking Crude; Robots Head to the Rescue
80beats: Obama Proposes Oil & Gas Drilling in Vast Swaths of U.S. Waters
80beats: 21 Years After Spill, Exxon Valdez Oil Is *Still* Stuck in Alaska’s Beaches

Images: Jack Cook, WHOI; George Foulsham, UCSB

Over the past three years, I've blogged nearly every day at least once. Today I'm going on vacation... without a laptop! For the month of May, The Intersection will return to its roots as Chris Mooney flies solo once again, but he'll be in excellent company: I've lined up a series of terrific guest bloggers that will appear throughout the month! Readers can look forward to diverse contributions from several terrific writers and scientists and I hope you'll welcome them here and participate in comments. By the time I return, I'll be 30 times round that spectacular star of ours. So see you in June!

A few weeks ago I reviewed a paper on the the genetics of the Cape Coloured population. Within it there was a refrence to another paper, Deconstructing Jaco: genetic heritage of an Afrikaner. The title refers to the author himself. It was an analysis of his own pedigree going back to the 17th century, along with his mtDNA, his father’s mtDNA, and his Y lineage. The genetics is a bit thin, but the pedigree information is of Scandinavian quality from what I can tell. Praised the records of the Reformed Church!

The author’s utilizes an inversion of the typical method whereby a survey of a population may give some insight into individuals within that population. Rather, he leverages the thorough church records of his Afrikaner community, and his local roots, to paint a picture of his own ancestry. Then he compares the results to those of the community as a whole. Though an N of 1 certainly has limits it seems that the author concludes that he is relatively representative because some of the statistics that emerge out of pedigree analysis seem to fall in line with what genealogists working with the whole community have found. Additionally, it is clearly that he has deep roots within the historic Afrikaner nation, so assuming random mating and little population substructure, inferences from his pedigree may have some general utility.

Afrikaners apparently have some peculiarities genetically which has made them of some interest to scientists. It turns out that they seem to exhibit high frequencies of classical Mendelian diseases, a hallmark of inbreeding or population bottlenecks. This aligns well with the thesis that Afrikaners are the descendants of a small group of founders who arrived in the 17th century and entered into a long phase of demographic expansion, which culminated with their long Trek into the veld to escape English domination as well as perpetuate their practice of slavery (James Michner’s The Covenant is a fictionalization of this). As I have observed before the primacy of the “first settler” seems to loom large in the minds of demographers.

J. M. Greef, the author of the above paper, seems to refute this simple story in his own genealogy, though not the core aspect of the importance of the first founders. First the abstract:

It is often assumed that Afrikaners stem from a small number of Dutch immigrants. As a result they should be genetically homogeneous, show founder effects and be rather inbred. By disentangling my own South African pedigree, that is on average 12 generations deep, I try to quantify the genetic heritage of an Afrikaner. As much as 6% of my genes have been contributed by slaves from Africa, Madagascar and India, and a woman from China. This figure compares well to other genetic and genealogical estimates. Seventy three percent of my lineages coalesce into common founders, and I am related in excess of 10 times to 20 founder ancestors (30 times to Willem Schalk van der Merwe). Significant founder effects are thus possible. The overrepresentation of certain founder ancestors is in part explained by the fact that they had more children. This is remarkable given that they lived more than 300 years (or 12 generations) ago. DECONSTRUCT, a new program for pedigree analysis, identified 125 common ancestors in my pedigree. However, these common ancestors are so distant from myself, paths of between 16 and 25 steps in length, that my inbreeding coefficient is not unusually high (f approximately 0.0019).

Inbreeding coefficient is the probability that one’s two alleles are identical by descent. That is, they come from the same individual. For example, in the case of Elisabeth Fritzl her children have many genes where the alleles are identical by descent because half of her own genes are from her father, some many of his alleles will come back to reside within the same individual as part of a diploid pair. J. M. Greef notes that his inbreeding coefficient is about twice as high as is the norm for the typical European. Europe is a region of relatively low consanguinity, so this is a stringent reference. In some populations the inbreeding coefficient can be as high as 0.01. In short, he’s not too inbred.

That being said, the data within his pedigree do seem to show disproportionate contribution by some ancestors. This makes sense for two primary reasons. First, some component of reproductive variance is random (often modeled as a poisson distribution). Second, some component of reproductive variance is due to innate fitness (e.g., the Genghis Khan Y haplotype may be a case of this). Equality of contribution just isn’t in the cards.

Figure 2 shows the distribution of relationships within the pedigree:

Panel a illustrates that one individual is an ancestor of the author 30 times over! Many individuals are ancestors only once. Panel b shows relatedness, and again, some individuals are much closer to the author than others, with a skewed distribution. Panel c shows the number of generations between the ancestor and the author. The median number is well above ten generations, so the author has deep roots in South Africa. Finally, panel d shows the number of steps between his parents for any given ancestor. Because the author’s parents are both Afrikaners they share many common ancestors, but the steps between seem relatively large, and confirms that the author is not particularly inbred (if the parents were first cousins naturally there would be much shorter steps to common ancestors). It is clear disproportionate amount of J. M. Greef’s genes come from early settlers. This makes sense insofar as demographic expansion was likely front loaded, with later settlers having less of a chance to make an impact on an already large population.

The following table shows the contribution by various European and non-European groups to the author’s ancestry, as well as estimates for the total Afrikaner population in earlier studies on the right.

Note one point: only a minority of the ancestry of the author and Afrikaners are ethnically Dutch. This is important, because it shows how culture can spread and overwhelm ancestry. The Dutch imposed their language upon the French Huguenots, and their religion upon the Germans (who I presume were mostly Lutheran if they were from northern Germany, though a minority were Reformed or Catholic surely). Obviously the Reformed Calvinist religion and Afrikaans language both have a unique stamp in South Africa, but the connection of the Afrikaners to the Netherlands remained profound rather late in history. The Prime Minister of South Africa from 1958-1966 was born in the Netherlands. And yet another fact hard to deny is that the Huguenot French component seems to have persevered to a greater extent culturally than the German. The last Afrikaner President was named F. W. de Klerk, his surname being a form of Le Clerc. Another prominent South African head of state was Daniel Francois Malan. The author observes:

It is not clear if my higher estimate of French contribution is because of a systematic mistake in Heese’s (1970) estimate, or if it is because of a quirkiness in my own ancestry. It seemed to be the case that when a lineage hit the French Huguenots it stayed in this group. It will be interesting to compare the degree of inbreeding of the early generations of Huguenots to the other early immigrants. In the light of the calculations of Heyer et al. (2005) there is an interesting possibility that the cultural inheritance of fitness may have led to a systematic bias in Afrikaners, since Huguenots tended to be more educated and trained than German emigrants who tended to be soldiers. We are currently investigating this hypothesis.

There is a joke that the Baltic possessions of the Swedish monarchy were conquered with Finnish soldiers. Similarly, the Dutch overseas colonial possessions were staffed, especially at a lower level, by the rural male population surplus of northern Germany. A great many of these, likely the vast majority, never returned home and died abroad. These men contributed greatly to the census size of the Afrikaner population during much of its history, but it seems plausible that their fitness was far lower than the established Dutch and Huguenot groups because they lacked the resources and capital to flourish in a world which was much closer to the Malthusian edge than today. Many people don’t leave descendants, and it seems plausible that these Germans were fated not to do so to a far greater extent than the Dutch and Huguenots whom they were employed to protect and serve. Because of the genetic closeness of the north German and Dutch populations (in reality, Dutch are really simply another group of north Germans who transformed their regional identity into a national one for various reasons) I doubt that more thorough genetic testing will resolve this, rather, more pedigree analysis needs to be done on other individuals. But it’s an insight into the fact that social parameters have often been crucial to fitness in the human past.

As for the non-white component, the author’s results match those of previous researchers. He confirmed the likely probability of these results by the fact that his father carries mtDNA group M, which is most diverse in India. And in fact his father’s maternal lineage does trace back to a woman who was likely an Indian slave (slave women had particular surnames indicating their origin). My previous posts on the Coloureds highlighted the large Asiatic component to their ancestry, and it looks like previous researchers ignored this and focused on the Khoisan and Bantu. They also attempted to calculate ancestry based on classical markers which were found in African populations, and are present in low frequencies in Afrikaners, but that might ignore Asian signature markers (additionally, I assume that there was some natural selection for G6PD alleles). A survey of the total genomes of Afrikaners should be able to resolve the details of their ancestry, but it seems that the Afrikaners are far more colored than white Americans, by a factor of 5, but far less than white Latin Americans like Argentineans, probably by a factor of 5.

Finally, the author was also able to assess whether his ancestors exhibited a trade between quantity and quality in terms of their optimal number of offspring. In other words, did those who favored an extreme r or K selected strategy suffer vis-a-vis those who produced a more moderate number of offspring, not too low, and not too high? The author did not find any evidence of a tradeoff, and an optimal fitness. He was careful not to generalize too much, especially in light of the fact that Dutch colonial South Africa was an atypical society in many ways. I assume that living on the frontier means not having to say you’re sorry if you breed too much or too little.

Citation: Greeff, J. (2007). Deconstructing Jaco: Genetic Heritage of an Afrikaner Annals of Human Genetics, 71 (5), 674-688 DOI: 10.1111/j.1469-1809.2007.00363.x

Last year, the UK press was abuzz with the so-called “expenses scandal”. In a time when the county was gripped by recession, we were told that Members of Parliament (MPs) were claiming for all sorts of ridiculous luxuries, all at the taxpayer’s expense. The revelations dominated the news, but the idea that people in positions of power often behave hypocritically isn’t new. It is said, after all, that power corrupts. Now, Joris Lammers from Tilburg University has found solid evidence for this.

Through five compelling experiments, Lammers has shown that powerful people are more likely to behave immorally but paradoxically less likely to tolerate immorality in other people. Even thinking about the feeling of power can trigger these double standards.

To begin with, Lammers asked 61 students to remember a time when they either felt powerful or powerless. Those that reminded themselves of power were more likely to frown on cheating; compared to the powerless group, they thought that overclaiming on travel expenses was less acceptable. However, they were also more likely to cheat. Lammers gave the recruits the chance to decide how many lottery tickets they would receive by privately rolling two dice. Those who were primed with power were more likely to lie about their scores to wangle extra tickets.

To explore this hypocrisy further, Lammers did three further experiments where he manipulated a volunteer’s feelings of power and then gave them a common moral dilemma. All of these involved acts that are technically illegal but that many people take part in, such as speeding or tax-dodging. Their job was to say either whether they would be okay with doing it themselves, or whether they would think it acceptable if someone else did it.

He asked 42 students to take part in a simulated government, playing the part of either a prime minister or a low-ranking civil servant. Afterwards, he asked them if it was okay for them or others to break the speed limit when late for an appointment. A second group of 88 students were told to imagine a past feeling of power or powerlessness and asked if it’s okay to turn a blind eye to freelance wages on a tax declaration. Finally, a third group of 42 students had to do a word-search puzzle, where the hidden words signified either power or the lack of it. They were asked about the ethics of keeping a bike that was stolen and abandoned, if you don’t have enough money to buy one yourself.

Despite the different psychological manipulations and moral dilemmas, all three experiments found the same trends – the volunteers who felt more powerful were also more hypocritical. They frowned more strongly upon speeding, tax-dodging or keeping stolen goods, but were more lenient about doing it themselves. All these effects were statistically significant, and a questionnaire revealed that the tests didn’t affect the volunteers’ moods. None of them guessed the true purpose of the research.

As a final experiment, Lammers asked 105 students to write about an experience of power or powerlessness. But this time, half of them had to describe a time when they were actually entitled to that status, while the others described a time when the position wasn’t deserved. When asked about their opinions on keeping stolen goods, the only hypocrites were those with legitimate power.

It seems that power breeds a sense of entitlement, where people feel that they can take more than other people, but also dictate how others should behave. They can preach without the need to practice. But this hypocrisy hinges on the legitimacy of their power. Power corrupts, but it seems that only true power truly corrupts.

In these last four experiments, Lammer also found the opposite effect, where the ‘powerless’ groups (and the illegitimately powerful one) showed a sort of anti-hypocrisy. They were harsher about their own transgressions than those of other people’s. Lammers refers to this as ‘hypercrisy’, from the Greek for ‘too much criticism’.

You can easily imagine how this combination of hypocrisy and hypercrisy fuels the gap between the haves and the have-nots in human societies. The powerful impose their strict standards on other people while acting with greater abandon themselves. The powerless follow their own rules more rigidly, even though they are less willing to impress those rules on others.

It’s a vicious cycle, but one that can be broken if people point out that power hasn’t been earned. There are many ways of doing that, from open revolution to open derision, from flaming pitchforks to fiery satire. Either way, as Lammers says, if a leader’s reputation is undermined, “they may be inspired to bring their behavior back to their espoused standards. If they fail to do so, they may quickly lose their authority, their reputation, and—eventually—their power.”

Reference: Psychological Science http://dx.doi.org/10.1177/0956797610368810

More on psychology and power:

• Feeling powerless impairs higher mental abilities
• Holding heavy objects makes us see things as more important
• People who think they are more restrained are more likely to succumb to temptation

It’s on reduced marine predator size and how it effects the distribution of biomass. Remember you can find it on iTunes under “ResearchBlogCast.” Next week I pick the paper….

Last week I was emphasizing the fact that someone from Max Planck seemed to really be positive about the University of New Mexico research which indicates that there has been “archaic” admixture into the modern human lineage derived from Out-of-Africa. This was curious because Svante Pääbo is at the Max Planck Institute, and he’s reconstructing the Neandertal genome. I wasn’t going to do more than hint at rumors, so I’ll point to Thomas Mailund (after linking to posts on the topic of admixture or not) :

I really look forward to reading the Neandertal paper and see what it has to say about gene flow between us and Neandertals. A few month ago, while I visited his group in Leipzig, Svante Pääbo actually promised to show me the draft, but it never happened. In Ohio in February I talked to one of the authors on the paper and he wouldn’t reveal anything… I guess I just have to wait and can only hope that it won’t be too long.

Remember that I didn’t say anything, Thomas Mailund did. Though he wasn’t explicit either, so whatever conclusions you draw are your own. But perhaps a reminder that when people are talking about things in public that might seem curious or a bit farther than the evidence warrants, it may be an issue of you not knowing what they know.