The Arctic is screaming

Alexis Madrigal of The Atlantic (where else) has a detailed post on this year’s Arctic sea ice measurements. They’re lower than they’ve ever been, they could get even lower; as one scientist said about the previous year’s low, in 2007, “the Arctic is screaming”: 

Even this might not tell the whole story, because this chart only measures the visible sea coverage of the ice. It doesn’t measure how thick the ice is, and one theory is that the ice is thinning, therefore it’s melting faster, therefore the sea ice coverage declines year on year.

In the year of a US presidential election, when one of the candidates is denying man-made climate change, and the other doesn’t seem too minded to do that much about it, perhaps we need to find ways of giving Arctic ice a voice at the ballot box.

The Mystery at the Heart of This Years Record-Setting Arctic Ice Melt – Alexis C. Madrigal – The Atlantic.

BBC brain-training experiment makes it to Nature

From Nature, some science brought to you by BBC Lab-UK. Congrats to the team:

‘Brain training’, or the goal of improved cognitive function through the regular use of computerized tests, is a multimillion-pound industry1, yet in our view scientific evidence to support its efficacy is lacking. Modest effects have been reported in some studies of older individuals2, 3 and preschool children4, and video-game players outperform non-players on some tests of visual attention5. However, the widely held belief that commercially available computerized brain-training programs improve general cognitive function in the wider population in our opinion lacks empirical support. The central question is not whether performance on cognitive tests can be improved by training, but rather, whether those benefits transfer to other untrained tasks or lead to any general improvement in the level of cognitive functioning. Here we report the results of a six-week online study in which 11,430 participants trained several times each week on cognitive tasks designed to improve reasoning, memory, planning, visuospatial skills and attention. Although improvements were observed in every one of the cognitive tasks that were trained, no evidence was found for transfer effects to untrained tasks, even when those tasks were cognitively closely related.

via Access : Putting brain training to the test : Nature.

Neanderthal genes

Blimey. They sequenced the Neanderthal gene. Amazing:

This was an impressive technical feat. The DNA was extracted from a few bone fragments, and it was grossly degraded: the average size of a piece of DNA was less than 200 base pairs, much of that was chemically degraded, and 95-99% of the DNA extracted was from bacteria, not Neandertal. An immense amount of work was required to filter noise from the signal, to reconstruct and reassemble, and to avoid contamination from modern human DNA. These poor Neandertals had died, had rotted thoroughly, and the bacteria had worked their way into almost every crevice of the bone to chew up the remains. All that was left were a few dead cells in isolated lacunae of the bone; their DNA had been chopped up by their own enzymes, and death and chemistry had come to slowly break them down further.

via Neandertal! : Pharyngula.

And, as PZ Myers points out in his fascinating article:

Just for reference: these samples are 6-7 times older than the entire earth, as dated by young earth creationists. The span of time just between the youngest and oldest bones used is more than six thousand years old, again, about the same length of time as the YEC universe. Imagine that: we see these bone fragments now as part of a jumble of debris from one site, but they represent differences as great as those between a modern American and an ancient Sumerian. I repeat once again: the religious imagination is paltry and petty compared to the awesome reality.

You're a virus (well, bits of you are)

This little Nature precis is food for thought, though I confess to not understanding two thirds of it (and to beginning to wonder just which part of me is doing the thinking). Essentially, it’s a discussion of the fact that we have genetic material which looks very much like the borna disease virus (BDV) embedded in our genome, probably a result of historical integration into the chromosome of germline cells. And here’s the little kicker at the end:

The fact that Horie and colleagues1 could readily detect BDV DNA and chromosomal insertions in human cells suggests that BDV retroposition might occur at an appreciable frequency during BDV infection, creating a source of mutation in infected individuals (Fig. 1b). This yields a tantalizing and testable hypothesis for the alleged, but still controversial, causative association of BDV infection with certain psychiatric disorders, such as schizophrenia and mood disorders2, 11. This possibility becomes even more intriguing when considering the recent demonstration of L1 hyperactivity in the human brain12, the primary site of BDV infection.

via Virology: Bornavirus enters the genome : Article : Nature.