Archive for January, 2009

5-part interview with Greg Cochran

By Razib Khan | January 31, 2009 4:53 am

The 10,000 Year Explosion: How Civilization Accelerated Human Evolution, is now available from Amazon & fine local bookstores. Over at 2 Blowhards one of the authors Greg Cochran has done a 5-part interview: part 1, 2, 3, 4 and 5. Set some time aside, there’s a lot there….


Which netbooks are good?

By Razib Khan | January 31, 2009 4:47 am

I’m thinking of getting a netbook. Any recommendations/experiences?


Pajamas Media goes down….

By Razib Khan | January 31, 2009 1:59 am

Well, it isn’t just the old media that’s having issues. A few days ago Culture11 folded. Now it looks like Pajamas Media network is shutting down (they’re going to go into vlogging fulltime?). I got a few links from PM back in 2005-2006, very little traffic. It didn’t seem like the aggregation was adding any value to the constituent weblogs. Additionally, a lot of their stuff is 2001-2004 vintage Right-of-Center media commentary, the sell-by date has long passed. Something like The Next Right is what circa 2010 conservative weblogs are going to look like, at least the good ones. Look at this DJ Drummond level of idiocy last fall at PM:

Read More


Interracial sex or Mendelian segregation?

By Razib Khan | January 30, 2009 4:15 pm

sandrawithparents.jpgOver at The Root Keith Adkins has a post, Sandra Laing: Born Black with White Parents:

I’m no geneticist or biologist, but it looks like Sandra is a product of an black South African and maybe a white Afrikaneer. I’m saying, it looks like somebody in her family was lying. The tests they used to prove her father’s paternity could have been faulty. And what about proving her mother’s maternity? Is it possible she was adopted? Is it possible Sandra’s mother was “getting love” from a undeniably-black man on the side? I’m not trying to throw salt on Laing’s game, I’m just not convinced the complete truth has been unearthed. I need to see more cases like this to be convinced these particular extremes are probable. Again, I know anything it could be true, but Laing’s story is extreme. If you’re in the Los Angeles Skin screens next month at the Pan African Film Festival before getting wider release.

The film which Adkins refers to is Skin, a biopic based on Sandra Laing’s life. A few years ago I thumbed through a book which detailed Laing’s tumultuous life, When She Was White: The True Story of a Family Divided By Race. Obviously the fact that a child who was obviously of non-white ancestry was born to conservative Afrikaner parents during the period of apartheid is a story which elicited some interest in South Africa at the time, and the “talk of the town” very literally. Sandra Laing’s paternity was under some debate, and it was a working assumption by many that the mother was unfaithful. Rather primitive blood tests did not reject that Laing’s putative father was her father, and one should probably modulate down the likelihood of a white woman having an affair with a black man in apartheid South Africa, and, keeping the child. How do we assess the probabilities of paternity vs. re-expression or recombination of genetic variants which code for African phenotypes within the Afrikaner population?

Read More


By other means necessary?

By Razib Khan | January 30, 2009 2:05 pm

My friend Aziz Poonawalla has a post up, is evolution sufficient? No, it’s not the standard Creationist cant:

The implication of such rapid evolution is that we should actually notice it on human timescales. And that there is actually is some mechanism of action that is actually driving the mutations themselves – cosmic rays? transcription errors? normal statistical variance?
It seems that if we aren’t mutating at a rate comparable to above, then some sort of alternative mechanism must also be operating to accelerate the changes in DNA required to evolve from one species to another. There’s certainly some evidence that there are such “neo-Lamarckian” processes at work, The case of the humble water-flea certainly is not explicable by normal Darwinian processes.

The general question is tackled in 10,000 Year Explosion. I haven’t kept up on the literature of human evolution in the context of our separation from the lineage that led up to chimpanzees to comment in detail, but the big issue I would say to a physicist like Aziz is that there more degrees of freedom in biology than can imagined in your philosophy my friend! Leave a comment over at Aziz’s.
Related: Also at Talk Islam.


Australian Aboriginal morbidity & mortality

By Razib Khan | January 29, 2009 4:09 pm

A few years ago PLoS Medicine published Eight Americas: Investigating Mortality Disparities across Races, Counties, and Race-Counties in the United States. The results were:
— Asian-Americans, per capita income of $21,566, life expectancy of 84.9 years.
— Northland low-income rural Whites, $17,758, 79 years.
— Middle America (mostly White), $24,640, 77.9 years.
— Low-income Whites in Appalachia, Mississippi Valley, $16,390, 75 years.
— Western American Indians, $10,029, 72.7 years.
— Black Middle America, $15,412, 72.9 years.
— Southern low-income rural Blacks, $10,463, 71.2 years.
— High-risk urban Blacks, $14,800, 71.1 years.
That’s a 13.8 year difference between inner city blacks and Asian Americans.
Now, from The health and welfare of Australia’s Aboriginal and Torres Strait Islander peoples 2003:

…Indigenous life expectancy at birth is 20 years less than for the total
population, 56 years for Indigenous males compared to 77 years for all
Australian males and 63 years for Indigenous females compared to
82 years for all Australian females for the period 1999-2001….

Read the whole report for the greatly increased rates of alcoholism and other morbidity and mortality enhancing behaviors among indigenous Australians, but check out this breakdown of various increased risks for diseases (adapted from Wikipedia, but the source is the report linked above):

Read More

CATEGORIZED UNDER: Anthroplogy, Genetics

Has it awakened?

By Razib Khan | January 29, 2009 1:59 am

Mars Rover Disoriented Somewhat After Glitch:

More strangely, the Spirit had no memory of what it had done for that part of Sol 1800. The rover did not record actions, as it otherwise always does, to the part of its computer memory that retains information even when power is turned off, the so-called nonvolatile memory. “It’s almost as if the rover had a bout of amnesia,” said John Callas, the project manager for the rovers.
Another rover system did record that power was being drawn from the batteries for an hour and a half. “Meaning the rover is awake doing something,” Dr. Callas said. But before-and-after images showed that the Spirit ended the day exactly where it started.



Navigenics, a joke?

By Razib Khan | January 28, 2009 10:00 pm

Read Genetic Future on Navigenics crappy new product. Better yet, link to the post yourself to crank up the google ranking, you’re doing potential consumers a service.


The Immortal

By Razib Khan | January 28, 2009 5:07 pm

There are now some articles which are detailing the other Ponzi schemes which are coming out in the wake of l’affaire Madoff. One thing that is notable: the next biggest scam is an order of magnitude less significant. That is, while Bernie Madoff’s scam was on the scale of billions, the next ones in the rank order are on the scale of hundreds of millions. If you haven’t read The New York Times‘s piece which speculates on the psychological roots of Bernie Madoff’s skill at extracting money from the wealthy, you should read it. It’s nothing surprising, most people I’ve discussed the details of Bernie’s modus operandi immediately assume some sort of sociopathy. I would note though that sometimes there is a fine line between salesman and con-artist. In modern America the distinction seems obvious, but in a world of haggling and caveat emptor these were two faces of the same coin. Additionally, a commonly quoted number for the compensation forms sent to those conned by Bernie are 8,000. But this doesn’t include everyone who was screwed by the funds-of-funds. It seems that Bernie Madoff will be a name that will echo down the generations, because thousands of families have likely lost their perches in the upper class because of this fiasco. There will be children later this century who might be told that but for Bernie Madoff they would have been American aristocracy (though to be fair, many will not be told that because of Bernie Madoff many of their forebears became American aristocracy)….


MAOA & aggression

By Razib Khan | January 28, 2009 9:46 am

Monoamine oxidase A gene (MAOA) predicts behavioral aggression following provocation:

Monoamine oxidase A gene (MAOA) has earned the nickname “warrior gene” because it has been linked to aggression in observational and survey-based studies. However, no controlled experimental studies have tested whether the warrior gene actually drives behavioral manifestations of these tendencies. We report an experiment, synthesizing work in psychology and behavioral economics, which demonstrates that aggression occurs with greater intensity and frequency as provocation is experimentally manipulated upwards, especially among low activity MAOA (MAOA-L) subjects. In this study, subjects paid to punish those they believed had taken money from them by administering varying amounts of unpleasantly hot (spicy) sauce to their opponent. There is some evidence of a main effect for genotype and some evidence for a gene by environment interaction, such that MAOA is less associated with the occurrence of aggression in a low provocation condition, but significantly predicts such behavior in a high provocation situation. This new evidence for genetic influences on aggression and punishment behavior complicates characterizations of humans as “altruistic” punishers and supports theories of cooperation that propose mixed strategies in the population. It also suggests important implications for the role of individual variance in genetic factors contributing to everyday behaviors and decisions.

I blogged this at Gene Expression Classic the other day, focusing on the “big picture” in terms of evolution. But I thought it was worth taking a closer look at the paper itself. The authors note a few issues in relation to MAOA, in particular for those who are known to have “low activity” genetic variants (MAOA-L):
1) Gene-environment interaction effects whereby abused children with MAOA-L are much more likely to become abusers than those who are MAOA-H (non-abused children show no difference).
2) Neuroimaging which shows greater reactivity in the amygdala and lower activity in the regulatory prefrontal areas during emotional arousal for MAOA-L individuals.
3) MAOA’s interaction with various neurotransmitters (or specific, the gene product’s interaction).
4) A family study where the subjects were generally criminal in inclination, and, were to be mostly MAOA-L.

Read More


Motivated minorities win!

By Razib Khan | January 27, 2009 9:37 am

Extremely readable OA paper in PNAS, Behavioral experiments on biased voting in networks:

Many distributed collective decision-making processes must balance diverse individual preferences with a desire for collective unity. We report here on an extensive session of behavioral experiments on biased voting in networks of individuals. In each of 81 experiments, 36 human subjects arranged in a virtual network were financially motivated to reach global consensus to one of two opposing choices. No payments were made unless the entire population reached a unanimous decision within 1 min, but different subjects were paid more for consensus to one choice or the other, and subjects could view only the current choices of their network neighbors, thus creating tensions between private incentives and preferences, global unity, and network structure. Along with analyses of how collective and individual performance vary with network structure and incentives generally, we find that there are well-studied network topologies in which the minority preference consistently wins globally; that the presence of “extremist” individuals, or the awareness of opposing incentives, reliably improve collective performance; and that certain behavioral characteristics of individual subjects, such as “stubbornness,” are strongly correlated with earnings.

To some extent this shouldn’t be that much of a surprise. How many French wanted to banish the Catholic Church from national life in the 1790s? Here’s the bottom line:

Read More


The 10,000 Year Explosion: How Civilization Accelerated Human Evolution

By Razib Khan | January 26, 2009 8:53 am

5152fXI3EtL._SL500_AA240_.jpgThe normal story we are told is that as rose civilization, so declined evolution. The 10,000 Year Explosion: How Civilization Accelerated Human Evolution, inverts that formula as indicated by the title. The idea that humans are beyond evolution isn’t limited just to non-scientists, Steve Jones, an evolutionary geneticist, made the same argument last year. I’ve pointed why the emergence of modern culture and all its accoutrements, such as effective medicine, does not mean that the power of evolutionary forces are somehow negated. In The 10,000 Year Explosion Greg Cochran and Henry Harpending suggest that the rise of complex societies, and in particular agriculture, increased the tempo of evolution! Contrary to the idea that humanity is the post-evolutionary animal, Cochran & Harpending sketch out compelling reasons why one can not separate our biological heritage from our cultural development (and vice versa).

Read More


2 Blowhards interviews Greg Cochran

By Razib Khan | January 26, 2009 2:09 am

Michael Blowhard is doing a 4-part interview with Greg Cochran on his new book, The 10,000 Year Explosion: How Civilization Accelerated Human Evolution. Part 1 is up.



By Razib Khan | January 24, 2009 2:43 pm

Read More


Women with children work less

By Razib Khan | January 23, 2009 1:09 am

Sheril has a post up, On Sacrificing Reproductive Fitness For Career Advancement…, which makes a common sense point:

Angier references a recent survey of 160,000 Ph.D. recipients that found 70 percent of male tenured professors were married with children while only 44 percent of their female counterparts were. Further, twelve years or more after receiving doctorates, tenured women were more than “twice as likely as tenured men to be single and significantly more likely to be divorced.” Another California study reported nearly double the number of female faculty agree with the statement, “I had fewer children than I wanted,” compared to men. Angier sums it up:

I decided to check the mean number of hours worked last week against the number of children an individual had, and break that down by sex. Below the fold are the results.

Read More


How Ashkenazi Jewish are you?

By Razib Khan | January 22, 2009 3:44 pm

Carl Zimmer pointed me to a new paper, A genome-wide genetic signature of Jewish ancestry perfectly separates individuals with and without full Jewish ancestry in a large random sample of European Americans. The title is so informative that pasting the abstract is almost unnecessary, but here is the conclusion which gets to the point:

In conclusion, we show that, at least in the context of the studied sample, it is possible to predict full Ashkenazi Jewish ancestry with 100% sensitivity and 100% specificity, although it should be noted that the exact dividing line between a Jewish and non-Jewish cluster will vary across sample sets which in practice would reduce the accuracy of the prediction. While the full historical demographic explanations for this distinction remain to be resolved, it is clear that the genomes of individuals with full Ashkenazi Jewish ancestry carry an unambiguous signature of their Jewish heritage, and this seems more likely to be due to their specific Middle Eastern ancestry than to inbreeding.

There have been other papers which show that Ashkenazi Jews form a separate cluster from gentile whites in the United States. This is important again in the context of biomedical studies attempting to ascertain the genetic roots of particular diseases; population substructure (e.g., Jew vs. non-Jew) may result in confounded associations. Also, one of the authors of the paper is David Goldstein, author of the fascinating Jacob’s Legacy.
In any case, on to the PC charts where the real action is. Do note that I’ve resized and added explanatory labels here & there for clarity.

Read More


Monito del Monte, a little bit of Oz in South America

By Razib Khan | January 22, 2009 5:20 am

1182356555_extras_ladillos_.jpgThe Monito del Monte is the only extant member of its order, the Microbiotheria. This order is itself part of the superorder Australidelphia, which includes Australian Marsupials and the Monito del Monte, whose native habitat are the forests of Chile and Argentina. In other words, the Monito del Monte is more closely related to the Marsupials of Australia than to those of the New World.


To the big men go the women!

By Razib Khan | January 21, 2009 11:05 pm

Market forces affect patterns of polygyny in Uganda:

Polygynous marriage is generally more beneficial for men than it is for women, although women may choose to marry an already-married man if he is the best alternative available. We use the theory of biological markets to predict that the likelihood of a man marrying polygynously will be a function of the level of resources that he has, the local sex ratio, and the resources that other men in the local population have. Using records of more than 1 million men in 56 districts from the 2002 Ugandan census, we show that polygynously married men are more likely to own land than monogamously married men, that polygynous marriages become more common as the district sex ratio becomes more female biased, that owning land is particularly important when men are abundant in the district, and that a man’s owning land most increases the odds of polygyny in districts where few other men own land. Results are discussed with reference to models of the evolution of polygyny.

My piece for The Guardian, Monogamy: bucking the trend?, was fundamentally an argument against natural short term market forces.


Of clines and clusters

By Razib Khan | January 21, 2009 9:16 am

About every single post on human population clusters tend to shift into a discussion as to whether human variation is clinal, or where one can make assertions of discrete groups. I think it is fair to note that most of the populations sampled have been skewed to one locale. For example, “French” might mean a few hundred patients from hospitals in the Paris area. “Belgian” might be a few hundred patients in hospitals in Brussels. The “gap” between the French and Belgian cluster may simply have to do with the fact that the populations are not representative of their nationalities. Surely as the genetic data gets more fleshed out and the sample sizes increase to the point where there are no “Here Be Dragons” spaces on the maps many of the clusters will begin to exhibit some continuity with each other. On the other hand, I do thinking of this purely as changes in allele frequency removes some important information.
Consider an idealized circumstance where you have 11 demes positioned in a sequence. demescline.jpg

Read More


Christianity – Old Testament = Anti-Semitism?

By Razib Khan | January 20, 2009 3:00 pm

In the comments about the term Judeo-Christian the Marcionite tendencies of liberal Christianity was mentioned. Sometimes I have encountered the idea that a rejection of the Hebrew Bible within Christianity naturally results in Anti-Semitism (granted, the argument is often from neconservatives who are attempting to solidify the evangelical-neocon alliance). I decided to look into the GSS.

Read More


Discover's Newsletter

Sign up to get the latest science news delivered weekly right to your inbox!

Gene Expression

This blog is about evolution, genetics, genomics and their interstices. Please beware that comments are aggressively moderated. Uncivil or churlish comments will likely get you banned immediately, so make any contribution count!

See More


RSS Razib’s Pinboard

Edifying books

Collapse bottom bar