Science and Reason: Selected readings 2/6/10

Interesting reading and news items.

These items are also bookmarked at my Diigo account.

Five things you should know about climate change: It can be really difficult for anyone not well-versed in the debate to get any sense of the science at all, something that's clear from the huge gap between the scientific community's acceptance of climate change and the public's wariness about the topic. So it's probably useful to step back from the latest findings, and look at science's basic understanding of how greenhouse gasses can force climate change, which often gets lost in the arguments. [Nobel Intent, 11/29/09]
Genes vs. environment and the role of genomic "dark matter": The argument over the relative weight of nature and nurture-genes vs. the environment-has a history that predates anything that even resembles formal biology. With the advent of molecular biology and the completion of the human genome, we've now got a much better idea of what, precisely, genes contribute to human differences. [Nobel Intent, 12/8/09]
Skin Cells Turned into Brain Cells: Skin cells called fibroblasts can be transformed into neurons quickly and efficiently with just a few genetic tweaks, according to new research. The surprisingly simple conversion, which doesn't require the cells to be returned to an embryonic state, suggests that differentiated adult cells are much more flexible than previously thought. [Technology Review, 1/28/10]
Why Your DNA Isn't Your Destiny: At its most basic, epigenetics is the study of changes in gene activity that do not involve alterations to the genetic code but still get passed down to at least one successive generation. These patterns of gene expression are governed by the cellular material — the epigenome — that sits on top of the genome, just outside it. [Time, 1/6/10]
Fossils on the Edge of Forever: Astrobiologists have not yet found alien life on other planets. But the fossil record has evidence of aliens of another sort: the Ediacarans that lived on Earth millions of years ago. [Physorg.com, 12/14/09]
Acid oceans: the 'evil twin' of climate change: The sea lions, harbor seals and sea otters reposing along the shoreline and kelp forests of this protected marine area stand to gain from any global deal to cut greenhouse gases. These foragers of the sanctuary's frigid waters, flipping in and out of sight of California's coastal kayakers, may not seem like obvious beneficiaries of a climate treaty crafted in the Danish capital. But reducing carbon emissions worldwide also would help mend a lesser-known environmental problem: ocean acidification. [Physorg.com, 12/18/09]
Copenhagen Failed, Mexico is Already Doomed - What's Next?: Short of praying for volcanic activity to mitigate the harm of climate change, the best options are these. First, tell the truth, even when it sucks. Second, at least start paving the way for an ethic of sacrifice, so that people who are eventually forced by either events or the sudden arrival of new political realities - or most likely, both - actually have had a little time to prepare and are not wholly betrayed by the realization that this will cost us. [Casaubon's Book, 2/2/10]
Attractiveness, anger, and warrior princess blondes: So why does attractiveness (or perceived attractiveness) have a strong effect on entitlement and anger? The authors hypothesize that it has to do with social networks. Men who are strong and women who are...hot...attract people to them, men because they can protect people and because you don't want to get in their way, and women because you want a piece of that. [Neurotopia, 1/20/10]
Dark Materials: This evidence was further strengthened recently when astronomers observed the motion of stars in the Sagittarius dwarf galaxy. This galaxy collided with our Milky Way galaxy long ago, and its stars are now spread around ours in a diffuse stream. Astronomers measured the speed of these stars and again detected the effect of dark matter. Since these stars are spread all around our galaxy, astronomers could measure the distribution of the dark matter in our galaxy. The found that our galactic dark matter forms an asymmetrical squashed sphere. This clear lack of symmetry means it cannot be accounted for by modifying our gravitational theory. Dark matter is real, and it makes up the majority of mass in our galaxy. [Upon Reflection, 1/19/10]
A new, bigger kind of boom: A very massive star is supported against collapse by high energy photons (particles of light) which provide a pressure to push again gravity. However if the star is hot enough this mechanism can go horribly wrong. In a strange quirk of particle physics when photons are produced with a high enough energy, they can turn into an electron and its antiparticle, a positron. This process leads (with a few complex steps) to the star’s core becoming unstable and collapsing. This happens long before the star would have time to form an iron core. Such an event is called a Pair Instability Supernova (PISN) and only occurs with a star more massive than about 140 solar masses. [We are all in the gutter, 1/12/10]
Is the Earth even more sensitive to CO2 levels than we thought?: One of the more common arguments from skeptics of anthropogenic climate change is that the Earth has experienced periods during which atmospheric carbon dioxide levels were much much higher than they are today -- as much as 10 times higher. Why worry about a mere 30% increase over pre-industrial levels? [The Island of Doubt, 1/7/10]
Insulin resistance as a protective mechanism, a paradigm shift?: Oxidative stress has been implicated implicated in insulin resistance, and a new study by Hoehn et al. (1) adds some convincing evidence that one specific radical, superoxide generated in the mitochondria, may be a unifying cause. But the findings suggest that we may need to reconsider how we treat it. [Nutritional Blogma, 12/23/09]