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New satellite-based global drought severity index unveiled by researchers

Computers and Math from Science Daily Feed - Mon, 12/11/2017 - 11:09am
Just in time for the holidays, researchers are rolling out a new satellite-based drought severity index for climate watchers worldwide.
Categories: Science

Bumblebees solve the travelling salesman problem on the fly

New Scientist Feed - Mon, 12/11/2017 - 11:09am
While buzzing between flowers, bees can solve the maths dilemma called the travelling salesman problem by finding the shortest route that visits every blossom
Categories: Science

Battery research could triple range of electric vehicles

Matter and energy from Science Daily Feed - Mon, 12/11/2017 - 11:08am
New research could lead to the development of batteries that triple the range of electric vehicles, report scientists.
Categories: Science

A diamond as the steppingstone to new materials, using plasma physics technology

Matter and energy from Science Daily Feed - Mon, 12/11/2017 - 11:08am
Physicists have taken the first step in a five-year effort to create novel compounds that surpass diamonds in heat resistance and nearly rival them in hardness. Reserachers investigated how the addition of boron, while making a diamond film via plasma vapor deposition, changed properties of the diamond material.
Categories: Science

More effective photothermal tumor therapy with infrared light

Matter and energy from Science Daily Feed - Mon, 12/11/2017 - 11:08am
Nanorods made of bismuth sulfide kill tumor cells with heat when they are irradiated with near-infrared light (NIR). Scientists are now making these weapons more powerful by remodeling the defect state of the nanorod crystal lattice by adding gold nanodots. This could be a good basis for more effective photothermal treatment of tumors.
Categories: Science

New world standard in nano generators

Matter and energy from Science Daily Feed - Mon, 12/11/2017 - 11:04am
Engineers have developed a new way to produce electrical power that can charge handheld devices or sensors that monitor anything from pipelines to medical implants. The discovery sets a new world standard in triboelectric nanogenerators by producing a high-density DC current -- a vast improvement over low-quality AC currents produced previously. The devices can transform mechanical energy such as wind or vibrations into electricity.
Categories: Science

Midwife and signpost for photons

Matter and energy from Science Daily Feed - Mon, 12/11/2017 - 11:04am
Targeted creation and control of photons: This should succeed thanks to a new design for optical antennas.
Categories: Science

Graphene spin transport takes a step forward towards applications

Matter and energy from Science Daily Feed - Mon, 12/11/2017 - 11:04am
Researchers have predicted and demonstrated a giant spin anisotropy in graphene, paving the way for new spintronic logic devices.
Categories: Science

Bacteria development marks new era in cellular design

Matter and energy from Science Daily Feed - Mon, 12/11/2017 - 11:03am
Scientists have built a miniature scaffold inside bacteria that can be used to bolster cellular productivity, with implications for the next generation of biofuel production. Because there is a growing need for agricultural or renewable production of biofuels and other commodity chemicals to move away from fossil fuels, scientists have long sought to enhance the internal organization of bacteria and improve the efficiency of the cells for making nutrients, pharmaceuticals and chemicals.
Categories: Science

Asphalt-based filter now advanced to sequester greenhouse gas at wellhead

Matter and energy from Science Daily Feed - Mon, 12/11/2017 - 11:03am
Adding a bit of water to asphalt-derived porous carbon greatly improves its ability to sequester carbon dioxide, a greenhouse gas, at natural gas wellheads, report scientists. The filter is highly selective for carbon dioxide while letting methane pass through.
Categories: Science

How 3-D printed metals can be both strong and ductile

Matter and energy from Science Daily Feed - Mon, 12/11/2017 - 11:03am
A new technique by which to 3-D print metals, involving a widely used stainless steel, has been show to achieve exception levels of both strength and ductility, when compared to counterparts from more conventional processes.
Categories: Science

Messier 63 – the Sunflower Galaxy

Universe Today Feed - Mon, 12/11/2017 - 10:22am

Welcome back to Messier Monday! Today, we continue in our tribute to our dear friend, Tammy Plotner, by looking at the “Sunflower Galaxy”, otherwise known as Messier 63.

In the 18th century, while searching the night sky for comets, French astronomer Charles Messier kept noting the presence of fixed, diffuse objects he initially mistook for comets. In time, he would come to compile a list of approximately 100 of these objects, hoping to prevent other astronomers from making the same mistake. This list – known as the Messier Catalog – would go on to become one of the most influential catalogs of Deep Sky Objects.

One of these objects is the spiral galaxy known as Messier 63 – aka. the Sunflower Galaxy. Located in the Canes Venatici constellation, this galaxy is located roughly 37 million light-years from Earth and has an active nucleus. Messier 63 is part of the M51 Group, a group of galaxies that also includes Messier 51 (the ‘Whirlpool Galaxy’), and can be easily spotted using binoculars and small telescopes.

Description:

Messier 63 is what is known as a a flocculent spiral galaxy, consisting of a central disc surrounded by many short spiral arm segments – one not connected by a central bar structure. Drifting along in space some 37,000 light years from our own galaxy, we known it interacts gravitationally with M51 (the Whirlpool Galaxy) and we also know that its outer regions are rotating so quickly that if it weren’t for dark matter – it would rip itself apart.

Infrared image of the Sunflower Galaxy (Messier 63) taken by the Spitzer Space Telescope. Credit: NASA/JPL-Caltech/SINGS Team

As Michele D. Thornley and Lee G. Mundy, of the Maryland University Department of Astronomy, indicated in a 1997 study:

“The morphology and inematics described by VLA observations of H I emission and FCRAO and Berkeley-Illinois-Maryland Association (BIMA) Array observations of CO emission provide evidence for the presence of low-amplitude density waves in NGC 5055. The distribution of CO and H I emission suggests enhanced gas surface densities along the NIR spiral arms, and structures similar to the giant molecular associations found in the grand design spirals M51 and M100 are detected. An analysis of H I and H? velocity fields shows the kinematic signature of streaming motions similar in magnitude to those of M100 in both tracers. The lesser degree of organization along the spiral arms of NGC 5055 may be due to the lower overall gas surface density, which in the arms of NGC 5055 is a factor of 2 lower than in M100 and a factor of 6 lower than in M51; an analysis of gravitational instability shows the gas in the arms is only marginally unstable and the interarm gas is marginally stable. The limited extent of the spiral arm pattern is consistent with an isolated density wave with a relatively high pattern speed.”

There very well could be a massive object hidden within. As Sebastien Blais-Ouellette of the Universite de Montreal said in a 1998 study:

“In a global kinematical study of NGC 5055 using high resolution Fabry-Perot, intriguing spectral line profiles have been observed in the center of the galaxy. These profiles seem to indicate a rapidly rotating disk with a radius near 365 pc and tilted 50 deg with respect to the major axis of the galaxy. In the hypothesis of a massive dark object, a naive keplerian estimate gives a mass around 10^7.2 to 10^7.5 M.”

Infrared image of the M63 galaxy made by Médéric Boquien, using data retrieved on the SINGS project public archives of the Spitzer Space Telescope. Credit: NASA/JPL-Caltech

But that’s not all they’ve found either… How about a lopsided, chemically unbalanced nucleus! As V.L. Afanasiev (et al) pointed out in their 2002 study:

“We have found a resolved chemically distinct core in NGC 5055, with the magnesium-enhanced region shifted by 2″.5 (100 pc) to the south-west from a photometric center, toward a kinematically identified circumnuclear stellar disk. Mean ages of stellar populations in the true nucleus, defined as the photometric center, and in the magnesium-enhanced substructure are coincident and equal to 3-4 Gyr being younger by several Gyr with respect to the bulge stellar population.”

Yep. It might be beautiful, but it’s warped. As G. Battaglia of the Kapteyn Astronomical Institute indicated in a 2005 study:

“NGC 5055 shows remarkable overall regularity and symmetry. A mild lopsidedness is noticeable, however, both in the distribution and kinematics of the gas. The tilted ring analysis of the velocity field led us to adopt different values for the kinematical centre and for the systemic velocity for the inner and the outer parts of the system. This has produced a remarkable result: the kinematical and geometrical asymmetries disappear, both at the same time. These results point at two different dynamical regimes: an inner region dominated by the stellar disk and an outer one, dominated by a dark matter halo offset with respect to the disk.”

Sunflower Galaxy (Messier 63). Credit: Adam Block/Mount Lemmon SkyCenter/University of Arizona

History of Observation:

Messier Object 63 was the very first discovery by Charles Messier’s friend and assistant Pierre Mechain, who turned it up on June 14, 1779. While Mechain himself did not write the notes, Messier did:

“Nebula discovered by M. Mechain in Canes Venatici. M. Messier searched for it; it is faint, it has nearly the same light as the nebula reported under no. 59: it contains no star, and the slightest illumination of the micrometer wires makes it disappear: it is close to a star of 8th magnitude, which precedes the nebula on the hour wire. M. Messier has reported its position on the Chart of the path of the Comet of 1779.”

Messier 63 would go on to be observed and resolved by Sir William Herschel and cataloged by his son John. It would be descriptively narrated by Admiral Symth and exclaimed over by many astronomers – one of the best of which was Lord Rosse: “Spiral? Darkness south flowing nucleus.” Of all the descriptions, perhaps the best belongs to Curtis, who first photographed it with the Crossley Reflector at Lick Observatory: “Has an almost stellar nucleus. The whorls are narrow, very compactly arranged, and show numerous almost stellar condensations.”

Locating Messier 63:

The beautiful Sunflower Galaxy is among one of the easiest of the Messier objects to find. It’s located almost precisely between Cor Caroli (Alpha Canes Venetici) and Eta Ursa Majoris. With the slightest of optical aid, stars 19, 20 and 23 CnV will show easily in finderscope or binoculars and M63 will be positioned right around two degrees away towards Eta UM.

The location of Messier 63 in the Canes Venatici constellation. Credit: IAU/Sky & Telescope magazine (Roger Sinnott & Rick Fienberg)

While this spiral galaxy has a nice overall brightness, it’s going to be very faint for binoculars, only showing as the tiniest contrast change in smaller models. However, even a modest telescope will easily see a faint oval shape with a concentrated nucleus. The more aperture you apply, the more details you will see. As size approaches 8″ and larger, expect to see spiral structure!

Power up… And look for the spiral in the Sunflower!

Object Name: Messier 63
Alternative Designations: M63, NGC 5055, Sunflower Galaxy
Object Type: Type Sb Spiral Galaxy
Constellation: Canes Venatici
Right Ascension: 13 : 15.8 (h:m)
Declination: +42 : 02 (deg:m)
Distance: 37000 (kly)
Visual Brightness: 8.6 (mag)
Apparent Dimension: 10×6 (arc min)

We have written many interesting articles about Messier Objects here at Universe Today. Here’s Tammy Plotner’s Introduction to the Messier ObjectsM1 – The Crab Nebula, and David Dickison’s articles on the 2013 and 2014 Messier Marathons.

Be to sure to check out our complete Messier Catalog. And for more information, check out the SEDS Messier Database.

Sources:

The post Messier 63 – the Sunflower Galaxy appeared first on Universe Today.

Categories: Science

The date from hell

Why Evolution is True Feed - Mon, 12/11/2017 - 9:45am

Imagine going out on a first date and being mercilessly grilled and hectored about whether your views conform to Regressive Leftism.  Of course partners on any first dates vet each other from the outset, but it’s usually far more subtle than the strategy recommended by Lara Witt in her Everyday Feminism piece “10 things every intersectional feminist should ask on a first date” (first published at Wear Your Voice).  I won’t go into all the details, but she recommends to all woke peeps asking their dates (whether or not that date is of your gender or not) ten questions. If any of the answers aren’t right, you should ditch them.

Here’s how she starts the article (notice that the very first words give her “identity”), and then a list of the questions (all come with her explanations, but I’ve put down only the stuff for question #1). Take my word for it, these aren’t just things to suss out about your date, they are things you should explicitly ask about. 

As a queer femme of color, I keep close relationships with people who go beyond allyship; they’re true accomplices in the fight against white supremacy, queerphobia, and misogyny. If you’re not going to support marginalized folks, then we can’t be friends, let alone date. The personal is political.

Beyond the lovely cushioning, happiness and support that we receive from our platonic relationships (which are, in all honesty, soul-feeding and essential), feminists also date! But there are questions we have to ask before we get close to someone.

The following list of questions is applicable to all relationships — certainly not just cisgender, heterosexual ones:

  1. Do you believe that Black Lives Matter?
    Yes? Wonderful. Let’s start here. There are three categories that are non-negotiables for me: an understanding of race, class, and gender. Not everyone understands how these three can be insidious, systemic and intertwined, but anyone who doesn’t take the time to learn how systemic racism works isn’t going to care about how racism affects me or people who are darker-skinned than I am.I don’t want to have to have laborious discussions where I have to prove to someone that white privilege or non-black privilege exists. If they are willing to learn and listen and make the space to decenter their whiteness (if they are white), that’s a good place to start.
  2. What are your thoughts on gender and sexual orientation?
  3. How do you work to dismantle sexism and misogyny in your life?
  4. What are your thoughts on sex work?
  5. Are you a supporter of the BDS movement?
  6. What is your understanding of settler colonialism and indigenous rights?
  7. Do you think capitalism is exploitative?
  8. Can any human be illegal?
  9. Do you support Muslim Americans and non-Muslim people from Islamic countries?
  10. Does your allyship include disabled folks?

This is truly the date from hell. In fact, I’d run away about two or three questions in.

Witt used to write for Teen Vogue and Feministing, a slightly more mature version of Everyday Feminism. As for being “of color,” well, her mother is half-Kenyan and half Indian, and her father is white, and she explained at Feministing why she hates whiteness (note her privilege):

On paper I am a minority, but you wouldn’t necessarily know that when you see me. I come from a upper middle class family, I grew up in Switzerland, I got to travel a lot and I speak fluent english and french. In person, I can perform whiteness. I portray European-ness. But I know nothing else.

For years I have struggled with my mixed ethnicity because I don’t feel either Kenyan or Indian at all. I visited Kenya multiple times, my mother regularly made us chapati and biryani and painted our hands with henna. But at school I hung out with my friends of whom 80% were white. I could eat hundreds of chapatis, but that didn’t make me feel more Indian. I could spend time with a Maasai tribe and bead colorful necklaces for tourists, but that didn’t make me feel more Kenyan.

I have struggled with my ethnicity because although on paper I am a minority, I wasn’t taught that I was. I wasn’t taught my mother’s cultures. I don’t know how to speak swahili or punjabi. This means that I cannot communicate with my grandmother and some of my relatives. I know little about being Kenyan or Indian, I have little in common with the maternal side of my family. My mother made me white, she denied me half of who I am.

This is a rupture of my identity. I only know my whiteness and I feel guilty about this. I hate that I can only perform whiteness.

She’s clearly twisted up with confusion and hatred, which is why she tweeted this In March:

Also white people are evil. Whiteness is evil.

— Lara Witt (@Femmefeministe) March 18, 2017

Apparently her white husband (a male?) is an exception:

Witt’s Twitter feed is a compendium of Regressive Leftism. All I can say is that I’m glad I don’t have to deal with people like this. But apparently she doesn’t want to deal with people like me.

My nightmare is that some day a sizable number of Americans will be like this. I’m all for progressivism and anti-racism, but not when it’s as full of hatred as Witt is.


Categories: Science

A global north-to-south shift in wind power by end of century

Matter and energy from Science Daily Feed - Mon, 12/11/2017 - 9:04am
Wind resources in the next century may decrease in many regions in the Northern Hemisphere -- and could sharply increase in several hotspot regions down south.
Categories: Science

Unravelling the mysteries of extragalactic jets

Space and time from Science Daily Feed - Mon, 12/11/2017 - 9:04am
Researchers have mathematically examined plasma jets from supermassive black holes to determine why certain types of jets disintegrate into huge plumes.
Categories: Science

Hyperlens crystal capable of viewing living cells in unprecedented detail

Matter and energy from Science Daily Feed - Mon, 12/11/2017 - 9:04am
A fundamental advance in the quality of an optical material used to make hyperlenses makes it possible to see features on the surface of living cells in greater detail than ever before.
Categories: Science

Cold suns, warm exoplanets and methane blankets

Space and time from Science Daily Feed - Mon, 12/11/2017 - 9:03am
Three million years ago, the sun shone weaker, but Earth stayed surprisingly warm. Carl Sagan thought a greenhouse effect must have been to thank. A model built on 359 chemical processes has finally arrived at scenarios with a reasonable chance of producing the needed methane on ancient Earth. The model has broad parameters in hope that it may someday be of use to interpret conditions on exoplanets.
Categories: Science

The origin of the Andes unravelled

Matter and energy from Science Daily Feed - Mon, 12/11/2017 - 9:03am
Why do the Andes exist? Why is it not a place of lowlands or narrow seas? A geophysicist has been pondering these questions for more than a decade. Now, he has found the answers using an advanced computer model.
Categories: Science

Not-Mary’s Monday Metazoan: I think it’s beautiful anyway

Pharyngula Feed - Mon, 12/11/2017 - 8:58am

Mary’s away for another 8 days, which means I had to pick something. It’s a cave spider.

Califorctenus cacachilensis

So now everyone is as eager for her to get back home as I am!

Categories: Science

In an article on race and medicine, New York Times does its best to ignore and denigrate race

Why Evolution is True Feed - Mon, 12/11/2017 - 8:15am

Furthering my claim that the New York Times is becoming more regressive in its Leftism, we have a long article in the science section on race and medicine. The thing is, the author of the piece does his very best to pretend that there’s no such thing as “race”, even while investigating—and buttressing, to some extent—the connection between race (or ethnicity, if you will) and illness.  But the ideological petticoat of author Moses Velasquez-Manoff shows throughout, particularly at the end. Valasquez-Manoff, a science writer, lacks science degrees, which may explain his cluelessness about how scientists conceive of “race,” but, given that I tried to explain it to him in a long phone interview, I doubt it.

I’ve explained my take on “race” many times before, and you can search for it on this site. (If you want just one article, go here, which summarizes and glosses a like-minded piece from Quillette by Bo Winegard, Ben Winegard, and Brian Boutwell). Like virtually all geneticists, I don’t see a finite and absolutely discrete number of easily identifiable “races”—that’s a strawman that people like Velasquez-Manoff attack. Maybe the general public thinks this, but Velasquez-Manoff is talking to scientists and about accepted science here.  “Race” (or “ethnicity”, if you like that word better) is simply a term for human “ecotypes”: groups of different evolutionary ancestry that have evolved different traits.

Like many animal species, humans, especially during our evolution after we left Africa, were divided into relatively discrete groups that were geographically isolated from other groups. In the absence of frequent migration between areas (such as we have now), these groups differentiated genetically, and generally along lines of geography. (Barriers like oceans and mountains are formidable obstacles to inter-group mating!) That differentiation was due to either divergent forms of natural or sexual selection, or to random genetic drift.

You can see these differences using either DNA sequencing or morphology (physical traits). Although, as is well known, there is more genetic differentiation among individuals among one ethnic group or population than among different groups, you can nevertheless pick out these groups by using combinations of genes, for differences at one gene tend to be correlated with differences in other genes. So, for example, we can see clustering of genes among people from the Americas, Oceania, native Australians, Europe/Middle East, and East Asia, and this clustering enables their recognition as groups that evolved semi-independently.

The Winegard et al. paper gives several examples of how “ethnicity” is correlated with genetic clustering; here’s one quote:

Empirical studies bear this logic out. The geneticist Hua Tang and her colleagues, for instance, found that self-reported ethnicity corresponded almost perfectly with genetic clusters from 326 microsatellite markers  (a microsatellite marker is a piece of repetitive DNA in which a series of DNA base pairs are repeated). Other studies have demonstrated even more power to identify people’s ancestry accurately. These studies illustrate that, whatever the meaning of the claim that there is much more variation within than among races, researchers can, if they use the appropriate procedures, distinguish human ancestral groups from each other with remarkable accuracy. The significance of these genetic differences among groups is entirely an empirical question.

And my own words, which quote the Tang et al. paper:

Here’s a quote from the abstract of the Tang et al. paper, published in The American Journal of Human Genetics, an excellent journal. The article is free online:

Of 3,636 subjects of varying race/ethnicity, only 5 (0.14%) showed genetic cluster membership different from their self-identified race/ethnicity. On the other hand, we detected only modest genetic differentiation between different current geographic locales within each race/ethnicity group. Thus, ancient geographic ancestry, which is highly correlated with self-identified race/ethnicity—as opposed to current residence—is the major determinant of genetic structure in the U.S. population.

Despite the clear evidence that human populations are genetically different and differentiable—although the presence of clusters within clusters precludes us from picking out discrete “races” having sharp boundaries—ideologues pretend that these differences don’t exist or aren’t meaningful. That’s because they fear that recognizing different groups will lead to discrimination against those groups, for the very same reason that biological ideologues won’t consider the possibility that there are genetically based differences between the behavior and neurology of men and women. Recognizing differences, they fear, will lead to institutionalizing bigotry based on those differences: to racism and sexism. The article by Winegard et al. dismantles this idea handily. The truth is the truth, regardless of whether it fits your ideological biases. And we can and should promote equality on moral rather than biological grounds.

But Velasquez-Manoff doesn’t like the idea of race, and so when he’s trying to discuss whether we should base some medical decisions or treatment on ancestry or ethnic background, he gets all antsy. You can read the article for yourself:

Here are a few quotes from the piece that shows the author’s lack of understanding of a more sophisticated concept of “race”, and his attempt to dismiss the importance of geographic differences between human populations:

Professor Yudell belongs to a growing chorus of scholars and researchers who argue that in science at least, we need to push past the race concept and, where possible, scrap it entirely. Professor Yudell and others contend that instead of talking about race, we should talk about ancestry (which, unlike “race,” refers to one’s genetic heritage, not innate qualities); or the specific gene variants that, like the sickle cell trait, affect disease risk; or environmental factors like poverty or diet that affect some groups more than others.

Ummm. . . race and ancestry are pretty much the same thing, and if genetic differences aren’t innate qualities, I don’t know what they are. What Velasquez-Manoff means by “innate qualities” is probably stuff like IQ or behavior, controversial topics about which we have little firm knowledge with respect to ancestry. What we’re talking about here are genetic differences that may have an effect on the incidence of diseases like sickle-cell anemia and Tay-Sachs, (Valasquez-Manoff’s tortuous attempt to avoid concluding that sickle-cell anemia is more frequent in populations descended from West Africa then from other populations is amusing.)

Here’s more:

What’s new today is that modern genetic science has revealed just how arbitrary the old race categories — Negroid, Caucasoid, Mongoloid and so on — really are. Yes, there is variation in the human family, but there are few sharp divides where one set of traits ends and another begins. Rather, traits exist in gradients, reaching high frequency in some populations and lower frequency in others. As the geneticist Sarah Tishkoff of the University of Pennsylvania reminded me, human beings are too young as a species, too promiscuous and full of wanderlust, always moving and mixing, for the kind of separation and differentiation that would cause true speciation to have occurred.

Well, these categories are not completely arbitrary: they just don’t pick out the totality of genetically recognizable groups. And yes, there aren’t sharp divides between groups and traits (or genes), for we see groupings within groupings—exactly what you’d expect if humans formed populations that were semi-isolated after they left Africa.  And who on earth even claims that there are “true species” in humans? No scientist I know! We’re not reproductively incompatible or isolated, which is the criterion for true species. We simply differ in our traits and genes, which is what we call “subspecies” or “ecotypes.” Remember, genetic differences among ethnic groups are correlated, for groups became genetically differentiated as semi-isolated populations.

Velasquez-Manoff prefers medical diagnostics based on genes rather than ancestry, apparently not realizing that these are correlated. Yes, we’d like to know everyone’s full DNA sequence for the best medical treatment, but sometimes an ancestry-based approach is better, simply because some diseases are clearly correlated with ancestry (and I recognize that there’s a conflating issue of culture, which isn’t genetic), and because in most cases we don’t know which genes are involved in disease and which variants are associated with which conditions. So these paragraphs, for instance, are confused:

The takeaway from studies like this is that rather than relying on race, doctors should focus on the genes important to whatever puzzle they face — an approach often called “precision” or “personalized” medicine. The idea is that tailoring treatment to the patient’s genotype, not to skin color or hair texture, would improve outcomes.

Consider the case of kidney disease. Scientists have found that African-Americans fare worse than whites when it comes to this illness. The assumption had long been that some environmental factor explained the difference. But in recent years, scientists have linked certain variants of a gene called APOL1 to worse kidney-related outcomes. Those variants are enriched in people of African ancestry. Girish N. Nadkarni, a kidney specialist at Icahn School of Medicine at Mount Sinai in New York City, explained to me that scientists think this may be because those variants protect against the sleeping sickness endemic to some parts of Africa.

Yes, it would be good to have the APOL1 genotype of all patients, but look: here the author admits that there are genetic differences between groups that correlate with their ancestry. They just don’t show a perfect correlation. Further, there may be other genetic differences between groups beyond APOL1 that affect kidney disease, but we don’t yet know about them, and so might be able to use self-identified ancestry as a correlate of those unknown differences. This is why my own doctor, Alex Lickerman, uses “race” as a guide to diagnosing prostate cancer. He’s quoted in the article:

Alex Lickerman, founder of ImagineMD, a medical concierge service in Chicago, cites the example of prostate cancer. For unclear reasons, African-Americans have a higher risk than whites. One test for the cancer, which looks at prostate-specific antigen, is controversial because it can yield false positives. Some recommend against using it at all.

But Dr. Lickerman says that merely being aware that African-Americans have a higher disease risk impels him to order the test more often for African-American patients. To his mind, the elevated risk of cancer outweighs the risk of a false positive. “Race is a crude marker, but it’s a usable marker,” he said. In that respect, it is no different from other factors doctors consider, most of which are based on imperfect studies of limited size and scope, and need to be weighed carefully.

Note that Lickerman recognizes race as a sign of ancestry that is correlated with genetic differences—and the genes for prostate cancer probably haven’t all been identified. It’s better in this case to partly base tests on race than to do nothing in the absence of genotypic data. What Lickerman is doing here, which seems sensible, involves recognizing the reality of “race”.

When discussing the higher incidence of hypertension in African-Americans than in white Americans, Velasquez implicates racism. He doesn’t seem to recognize two things: that hypertension in American blacks might be due to other cultural differences, like diet, or that it might be due to an interaction between evolved black/white genetic differences with factors like diet. The author simply wants to flaunt his virtue by singling out racism as the likely cause:

African-Americans, who on average have about 20 percent European ancestry, suffer from high blood pressure more often than whites do. Some studies indicate that among African-Americans, the darker one’s skin, the greater the risk of high blood pressure. The pattern could indicate that African ancestry is responsible.

Yet Africans in Africa don’t generally have high blood pressure. So some argue that the experience of having dark skin in the United States — of experiencing racism — is what’s raising blood pressure. In this case, Dr. Burchard says, even though race is a social construct, the best way to talk about the associated disease risk may be to use the labels, since the societal baggage that comes with them may be causing the problem.

Note that Velasquez-Manoff fails to present alternative but even more credible hypotheses (I don’t think that experiencing racism is a more likely explanation for hypertension than is diet, for instance). At any rate, he fails to lay out both genetic and interactive explanations. And the notion that “race is a social construct” is simply ridiculous. If it were, Lickerman’s ministrations would be futile. If race were purely a social construct, ancestry and ethnicity wouldn’t be correlated with any biological factors.

Of course we’d like to have the DNA profile of all patients, but we’d also like more research on exactly which genes are associated with disease. Such genes, though, may be hard to identify because they have tiny effects. In the meantime, there are occasions, as with sickle-cell anemia and prostate cancer, that ethnicity, or “race”, or “self-identified race”, can be used meaningfully in a medical way. And that, of course, means that ethnicity is not a “social construct”, for it has biological meaning. That’s the point that the Winegard et al. article tries to make.

Velasquez-Manoff’s virtue signaling and distaste for any concept of race is most evident in his last paragraph:

Science seeks to categorize nature, to sort it into discrete groupings to better understand it. That is one way to comprehend the race concept: as an honest scientific attempt at understanding human variation. The problem is, the concept is imprecise. It has repeatedly slid toward pseudoscience and has become a major divider of humanity. Now, at a time when we desperately need ways to come together, there are scientists — intellectual descendants of the very people who helped give us the race concept—who want to retire it.

It’s pretty clear that he doesn’t like race because it “divides humanity.”  Well, it partitions humanity on the basis of genetic difference, but that’s not what he means. He means that genetic differences cause friction between people. The solution to that is not to pretend that the genetic differences don’t exist, but to stop them from creating bigotry and hatred.

And if you want, discard the word “race”—but let’s keep “ancestry,” shall we?. No biggie, since “ancestry” is a term that enlightened biologists see as closely associated with “race”. Should we retire the concept of “ancestry”, too? If so, then why does Velasquez-Manoff mention it repeatedly?

I have to say that when I talked to Velasquez-Manoff and tried to tell him about the more modern concept of “fuzzy” race that encompasses a variety of nested populations that differ genetically, I could sense that he didn’t like what I was saying. And at the time I got a bad feeling about what he was going to write, as I could sense him ignoring what I was trying to tell him. In fact, I’ll go so far as to say that he was determined at the outset to downplay the significance of genetic differences between ethnic groups. And that is surely reflected in his piece, which I found notably unenlightening and genetically ignorant, even if it was politically correct.


Categories: Science

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