Monday Science Links

This week's Science!

• Erik at Eruptions tells about Sarychev Peak: The eruption as Sarychev Peak seems to be waning a bit, at least according to some of the latest images from the NASA Earth Observatory's collection of MODIS shots. The ash plume is less prominent - and strikingly more grey than before, possibly if it contains a higher proportion of water vapor than the earlier plumes. However, it isn't these brand new shots that captured my attention but rather one of the possibly most stunning volcano images I've seen in years (above). This captures Sarychev Peak as a rare clear view appeared to the volcano through the clouds and we can see the ash column and pyroclastic flows moving down the flanks of the volcano. The image was taken from the ISS by one of the astronauts currently on the station and really, I am almost at a loss for words about how amazing this picture is.


• Over at Skulls in the Stars is a post about cloaking devices: When the first papers on the idea of a “cloaking” device came out in 2006, lots of people were immediately worried that the CIA would soon be peering right over their shoulder from the shelter of invisibility cloaks. Many scientists, including myself, pointed out the flaw in that reasoning: a “perfect” cloak would direct all light around the outside of the cloak. This meant that, although the spy couldn’t be seen in the cloak, he couldn’t see anything from inside! A recent paper in Physical Review Letters, however, suggests that this “mutual invisibility” can be overcome. The research described suggests that a different type of cloaking device could be used to enclose a sensing device, and that the sensor would not only be (almost) invisible, but it would be able to detect radiation just as well as when outside the cloak! The research is intriguing (though it still won’t help the CIA quite yet), and it illustrates a different, earlier, technique for making something “not be seen”.


• PZ over at Pharyngula posts on bird fingers: My previous repost was made to give the background on a recent discovery of Jurassic ceratosaur, Limusaurus inextricabilis, and what it tells us about digit evolution. Here's Limusaurus—beautiful little beastie, isn't it? What's especially interesting about it is that it catches an evolutionary hypothesis in the act, and is another genuine transitional fossil. The hypothesis is about how fingers were modified over time to produce the patterns we see in dinosaurs and birds. Birds have greatly reduced digits, but when we examine them embryologically, we can see precisely what has happened: they've lost the outermost digits, the thumb (I) and pinky (V), and retain the forefinger, middle finger, and ring finger (II-IV), which have been reduced and fused together. This is called Bilateral Digit Reduction, BDR, because they've lost digits from the medial and lateral sides, leaving the middle set intact.


• John Wilkins at Evolving Thoughts posts on news on apes and evolution: So there are a couple of interesting developments about fossil apes. One is the retraction by the author of the claim 14 years ago to have found a jaw bone that was evidence of Homo habilis, a precursor species (arguably) of H erectus, in a recent Nature. Previously he and his coauthor had claimed that erectus may have evolved in Asia and then returned back to Africa. On a re-examination of the evidence, Russell Ciochon now thinks that there is a “mystery ape”, around chimpanzee size, in the Asian forests, a possible precursor to orangutans. In the light of Homo floresiensis in the Indonesian Archipelago, however, it is clear that there had to be another hominid in South East Asia apart from erectus, as it is not likely to have evolved from an erectus precursor. If I recall a talk given by Colin Groves, of the ANU, he thinks that it is likely to have been a descendent of H habilis. So what is going on around 4-1 million years ago in Asia? There has long been a debate over two competing hypotheses: the Out of Africa hypothesis, and the Multiregional Hypothesis, for H sapiens, but this is independent of sapiens‘ evolution.


• Ethan at Starts With A Bang posts on the Herschel telescope's first picture: First light is one of the most important tests of any new telescope. It allows you to look at a well-known object, see if there are any problems with your telescope, and to get a small glimpse of how good your telescope is going to be.

Enjoy!