linkfest – 04/07/13

A Genome-Wide Association Study Identifies Five Loci Influencing Facial Morphology in Europeans“Our results also suggest that the high heritability of facial phenotypes seems to be explained by a large number of DNA variants with relatively small individual effect size, a phenomenon well known for other complex human traits, such as adult body height.”

The Genetic Correlation between Height and IQ: Shared Genes or Assortative Mating?“In this study, we used a large (total N = 7,905), genetically informative dataset to understand why two potentially sexually selected traits in humans—height and IQ—are correlated. We found that both shared genes and assortative mating were about equally important in causing the relationship between these two traits.”

ScienceShot: Monkey Smiles Are Contagious“Previously, only humans and orangutans had been shown to quickly and involuntarily mimic the facial expressions of their companions, an ability that seems to be linked to empathy.”

No evidence for higher testosterone in black compared to white adolescent males – @race/history/evolution notes.

Brain scans decode dream content“Researchers have decoded the content of people’s dreams using brain scanning technology”

Fertility and Happiness: A Global Perspective and A Fat World – With a Fat Secret? – from jayman (he was on a roll this week!).

Genes behind obesity mapped in large-scale study“An international research team has identified seven new gene loci linked to obesity.”

Is Psychometric g a Myth? – @human varieties. see also Is the g Factor a myth? from steve sailer.

Darwin: Are the races of man separate species or merely separate subspecies? – from steve sailer.

Inbreeding, race replacement, genetic disease, “diversity” – @race/history/evolution notes.

Wyld Stallyns and House O’Rats and Undecidable Propositions – from greg cochran (he was also on a roll this week!).

Have We Evolved to Be Nasty or Nice? – from matt ridley.

Shocker — married mothers smarter than single moms – from the awesome epigone.

Sex, models and housework – b.s. king takes a critical look at the (suspicious) maths behind that “sex and housework” story that made the rounds recently.

The Parsis“At present, we simply don’t know enough about Parsi history to understand what social and psychological characteristics may have been favored during the long centuries between the arrival of this community in India and its encounter with the British from the 17th century onward.” – from peter frost.

Mankind’s Collective Personalities – from john derbyshire.

Polynesian mtDNA in extinct Amerindians from Brazil – @dienekes.

Religiosity and fear of death: a three‐nation comparison“Overall, the patterns in all three countries were similar. When linearity was assumed, there is a substantial positive correlation between most religiosity measures and fear of death…. [F]emales were more religious and feared death more than did males, and Muslims expressed considerably greater fear than did members of any other major religion.” – @mein naturwissenschaftsblog.

Researchers see antibody evolve against HIV

Shocker: Colorado shooter on prescription psychiatric meds – @mangan’s.

The average human vagina – yes, there’s a lot of variation down there (sorry, no exciting pics @the link!).

Great Scientist ≠ Good at Math“E.O. Wilson shares a secret: Discoveries emerge from ideas, not number-crunching” – hmmmm. i still think that (*ahem*) being able to do maths is an awfully handy skill in biology, not to mention population genetics.

Could playing ‘boys’ games help girls in science and math?“[M]en and women with either a strong masculine or androgynous gender-identity fared better in mental rotation tasks.” – so, the women who were more guy-like were better at the mental rotation tasks. duh!

Global E-mail Patterns Reveal ‘Clash of Civilizations’“The global pattern of e-mail communication reflects the cultural fault lines thought to determine future conflict, say computational social scientists.”

In Praise of Kinship“You don’t have to be a relativist to see that one-size individualism can’t fit all cultures, or that clannish bonds are often deeply fulfilling.” – wsj review of mark weiner‘s book, The Rule of the Clan. see also What Modern Democracies Should Understand About Clan-based Societies Explored in New Book by Rutgers–Newark Law Professor.

bonus: The secret superdads: More than a dozen UK sperm donors have fathered 20 or more children EACH“Five-hundred men have sired more than 6,100 children in Britain”

bonus bonus: French people mired in ‘collective depression’“A new survey published on Thursday found that 70 percent of them see their country as afflicted by a ‘collective depression’, with two thirds believing that France is ‘in decline’…. ‘This deep French depression is explained in large part by a sense of lost identity.'”

bonus bonus bonus: Xenophobia has no effect on migrants’ happiness, says study

bonus bonus bonus bonus: An Emergency Hatch for Baby Lizards“Unborn lizards can erupt from their eggs days early if vibrations hint at a threat from a hungry predator, new research shows.”

bonus bonus bonus bonus bonus: Lego pulls toy following accusations of being anti-Islamic – but Lego denies discontinuing Jabba’s Palace over race claimspreviously.

bonus bonus bonus bonus bonus bonus: Boy, 17, builds DNA testing machine [polymerase chain reaction machine] in his bedroom to find out why his younger sibling has ginger hair

bonus bonus bonus bonus bonus bonus bonus: Chinese president urges openness, respect for diversity – of types of governments! (~_^)

(note: comments do not require an email. baby lizards! awwwww!)

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neuroglia

dipping into my vast knowledge of neuroglia cells (i.e. what i gather from reading the wikipedia entry about them), i can tell you that they…

“…are non-neuronal cells that maintain homeostasis, form myelin, and provide support and protection for the brain’s neurons. In the human brain, there is roughly one glia for every neuron with a ratio of about two neurons for every glia in the cerebral gray matter.

“As the Greek name implies, glia are commonly known as the glue of the nervous system; however, this is not fully accurate. Neuroscience currently identifies four main functions of glial cells: to surround neurons and hold them in place, to supply nutrients and oxygen to neurons, to insulate one neuron from another, and to destroy pathogens and remove dead neurons. For over a century, it was believed that they did not play any role in neurotransmission. That idea is now discredited; they do modulate neurotransmission, although the mechanisms are not yet well understood.

there are several types of glia cells, including astrocytes that among other things:

“– express plasma membrane transporters such as glutamate transporters for several neurotransmitters, including glutamate, ATP, and GABA. More recently, astrocytes were shown to release glutamate or ATP in a vesicular, Ca2+-dependent manner.
“– express potassium channels at a high density. When neurons are active, they release potassium, increasing the local extracellular concentration. Because astrocytes are highly permeable to potassium, they rapidly clear the excess accumulation in the extracellular space.
“– [promote] the myelinating activity of oligodendrocytes: Electrical activity in neurons causes them to release ATP, which serves as an important stimulus for myelin to form. However, the ATP does not act directly on oligodendrocytes. Instead, it causes astrocytes to secrete cytokine leukemia inhibitory factor (LIF), a regulatory protein that promotes the myelinating activity of oligodendrocytes. This suggest that astrocytes have an executive-coordinating role in the brain.”

why am i bringing up neuroglia and astrocytes and other unpronounceable brain parts? because the brain tumors (glioblastoma multiforme) that white men get way more than other groups are the kind (astrocytomas) that develop on or out of astrocytes.

and research suggests that there is something genetic behind this phenomenon:

“Ethnicity delineates different genetic pathways in malignant glioma”

“In the United States and the San Francisco Bay Area, whites are nearly twice as likely as non-whites to develop brain cancer…. Because whites have higher risk for glioma than non-whites in this population, that the gliomas from whites were less likely than those from non-whites to have p53 mutation suggests that whites may be more likely than non-whites to be at risk for the more common type of astrocytic gliomas, which do not contain p53 mutations.”

which makes me wonder if there was something in the evolutionary history of white men, a la the “Natural History of Ashkenazi Intelligence,” that makes them more prone to this type of tumor.

hmmmmmmm.

p.s. – ted kennedy had one of these astrocytomas.

previously: white males get more brain tumors

(note: comments do not require an email. male vs. female brains.)

white males get more brain tumors

specifically, adult gliomas:

“Demographic Variation in Incidence of Adult Glioma by Subtype, United States, 1992-2007”

“For race/ethnic group variation, we observed an important commonality between GBM [glioblastoma] and non-GBM. For each subtype, compared to non-Hispanic Whites, the incidence rate among Blacks, Asian/Pacific Islanders, and American Indians/Alaskan Natives was substantially lower (one-fourth to one-half for GBM; about two-fifths for non-GBM). However, secondary to this primary effect, race/ethnic group variation in incidence was less for non-GBM than for GBM, a difference that was highly statistically significant but only moderate in magnitude.

“There is evidence for race/ethnic group differences in genetic pathways to glioma [31-33]. Furthermore, genome-wide association studies have identified several genetic susceptibility regions for glioma [34,35]. Given the genotype variability across race/ethnic groups [36], it is possible that variation in the frequency of susceptibility alleles across race/ethnic groups explains at least some of the race/ethnic group variation in glioma incidence, including the race/ethnic group heterogeneity in the relationship between glioma incidence and age. The commonality between GBM and non-GBM in race/ethnic group variation suggests that at least some of the susceptibility loci that may help explain race/ethnic group variation in glioma incidence would be the same for GBM and non-GBM, although some susceptibility loci appear to show specificity with respect to glioma subtype [37-39]….

“As with race/ethnic group variation, we observed an important commonality between GBM and non-GBM for sex. For each subtype, the incidence rate was higher for males than for females; this male excess of glioma is well known [2,3,5,6]. However, we did find the male/female RR to be somewhat higher for GBM (1.6) than for non-GBM (1.4), a result that was highly statistically significant. We previously suggested that the male/female difference in brain cancer incidence is biologically based [1], and that an explanation should be sought in genetic differences between males and females, sex hormones, and/or female reproductive factors [40]. Now we would add that any explanation should take into account the difference in the male/female RR between glioma subtypes….”

related?: Natural History of Ashkenazi Intelligence

(note: comments do not require an email. just ignore them and they’ll go away.)