Month: May 2008

The human ‘super-organism’

The New York Times has just run a story by Nicholas Wade, 6 Tribes of Bacteria Found to Be at Home in Inner Elbow. The piece discusses new views on commensal bacteria, types of bacteria that live benignly on the body of a host. As the article points out, DNA culturing has really expanded our ability to study these bacteria because they are so difficult to sample and culture normally (in part because they need their host to live very long). The research is part of the federally funded human microbiome project, an attempt to catalogue all of the bacterial DNA that makes up the human ‘microbiome’ or what some call the human ‘super-organism’ (not because it can leap tall buildings but because a human ‘being’ turns out to be a walking system with staggering numbers of bacterial ‘beings’ as part of it).

Usually, articles like this make the point that, ‘no matter how hard you wash, every square inch of you is still covered in millions of bacteria…’ This article is no exception. But the article is also working with a lot more interesting data. For example: ‘The project is in its early stages but has already established that the bacteria in the human microbiome collectively possess at least 100 times as many genes as the mere 20,000 or so in the human genome.’ Bacteria cells outnumber the cells of the body itself as they are often quite a bit smaller than human cells.

Continue reading “The human ‘super-organism’”

Love Dem Bones

Sue Sheridan, who blogs as The Life of Wiley with updates on life, round ups, and comments on politics as well as biological anthropology, osteology, and more, posted this really cool image to the right when she linked to our student posts. On the left is one she put up yesterday.

If you want more of these images, check Sue’s blog out, as well as Primatebonz, the place where she helps contribute as well as scrounge over at Flickr. And she links to other image-laden sites like Skull-A-Day and Home of the Skulls. For real-life replicas (yeah, that made sense), check out Fossils as Art and Bone Clones. Bone Clones is one of my favorite exhibits to visit at anthro meetings. You haven’t lived until you’ve held a boisei skull in your hands!

Four Stones Worth

remote central has put up the latest Four Stone Hearth. Even on short notice (Tim took over for a blog that deleted itself), it’s a great version. Here are just a few highlights.

Puss ’N Boots slices his way through the evolution of mind and language.

If Inca neurosurgery is your thing, check out this nice square skull incision.

Mitochondrial Eve and Y-chromosome Adam get it on!

How about battle forks? Eat and fight at the same time! (Though I am personally more interested in the combo toothpick/earwax spoon.)

Neanderthals often get a bad wrap, but here’s the real deal about our bigger-brained cousins

The Swedes are swooning for their locked away booze

And finally, bite into some enamel chemistry—watch out, you were what you ate.

Wednesday Round Up #12

Drugs

Alexis Madrigal, Is Meth a ‘Smart Drug’?
Got to do my own promo… Wired is pretty cool

Not Exactly Rocket Science, Brain-enhancing Drugs Work by Focusing Brain Activity… For Better or Worse
A more brain-based take on the same thing: cognitive enhancers and context

Jonah Lehrer, The Hidden Cost of Smart Drugs
“Enhancement” and the loss of creativity

Vaughan Bell, How Neurotech Will Change the World, One Brain at a Time
“drugs and devices to cure diseases and optimise our brains”

Natasha Mitchell, Quitting the Habit: Neurobiology, Addiction and the Insidious Ciggie
The latest on smoking—quite a good show. Note that the transcript has lots of good links.

SparkNotes, Theories of Addiction
SparkNotes are study guides put together by Barnes & Noble. This one provides an overview of some basic psychobiological models.

Anthropology

Andy Coghlan, Religion a Figment of Human Imagination
Anthropologist Maurice Bloch argues that religion driven by imagination, not social cohesion

Scott London, The Ecology of Magic
Interview with David Abram, author of The Spell of the Sensuous

Scott Atran, The Religious Politics of Fictive Kinship
“friendship and others aspects of small group dynamics, especially acting together, trumping most everything else”

Heather Smith, Procrastinators without Borders
“Did perhaps just one anthropologist ever think to ask a penis-gourd-wearer if he wakes up some days and thinks he’s going to make a new penis gourd, but instead this happens and that happens, and making the new gourd just gets put off, along with everything else that he’s supposed to be doing, until he feels terrible and the only option seems to be to move to a place where no one notices that his gourd is outmoded?”

Continue reading “Wednesday Round Up #12”

Comfort Food and Social Stress

Comfort Food, for Monkeys is John Tierney’s article today, reporting on recent research by Mark Wilson and colleagues at Yerkes Primate Center about rhesus monkeys, sweet tooths, social stress and inequality. Familiar themes, all of them.

Normally, low-status monkeys eat roughly the same amount of bland monkey chow as dominant individuals. But add sweet banana-flavored pellets to the mix, and suddenly the equation changed: “While the dominant monkeys dabbled in the sweet, fatty pellets just during the daytime, the subordinate monkeys kept scarfing them down after dark.”

Tierney goes on to outline reasons why this scarfing vs. dabbling dynamic might emerge in socially complex species like rhesus monkeys. As Wilson et al. note in their paper, “this ethologically relevant model may help understand how psychosocial stress changes food preferences and consumption leading to obesity.”

Tierney describes research by Dallman et al., who have proposed that people can directly impact stress hormones through eating, largely by mediating anxiety: “[P]eople eat comfort food in an attempt to reduce the activity in the chronic stress-response network with its attendant anxiety.” So individuals with greater stress reactivity and negative mood tend to eat more in their stressed vs. control experimental paradigm.

As Tierney notes with a quip about a “stressed-out wage slave who has polished off a quart of Häagen-Dazs at midnight while contemplating the day’s humiliations,” inequality can bring on stress reactivity and negative mood (for more on that, see previous stress and inequality posts on Sapolsky and Blakey). In turn, inequality feeds into the obesity epidemic through both social and cultural dynamics.

But Tierney also knows that seeking food, not simply reactive eating, is key to overall weight gain. Continue reading “Comfort Food and Social Stress”