Probably the most talked about scientific issue that’s been making the rounds recently is the news is that not only has human evolution not stopped since the advent of modern technology, a previously popular view, but has in fact actually accelerated. As this article in ABC News notes, in a recent paper published in the Proceedings of the National Academy of Sciences in the United States, researchers discovered that by comparing the DNA of humans and chimpanzees since the two species diverged six million years ago there were not enough differences between the two sets of DNA to account for the currently observed rate of change. Therefore, they take this to mean that human evolution has substantially accelerated since the appearance of modern humans 40,000 to 50,000 years ago.
Moreover, they find that different populations of humans have been evolving in different ways. The lighter skin colour of Asians and Europeans compared to Africans is one example, as an adaptation to allow more absorption of vitamin D in areas with less sun. Another example is the disappearance of the lactase enzyme that allows digestion of fresh milk in China and most of Africa where dairy farming is less common than in Europe.
The most controversial example however is a reference to a previous study, entitled “Natural History of Ashkenazi Intelligence“, in which the rise of the intelligence of Ashkenazi Jews since medieval Europe was attributed to inbreeding and confinement to cognitively-demanding jobs. This was of course due to cultural reasons as usury was then forbidden to Christians and Jews found it difficult to be accepted in other forms of work. Together, these examples make for a compelling argument that cultural forces are driving human evolution to many different directions and put the old nature vs. nurture debate in a new light.
Next, the Washington Post has an intriguing report (registration required) on synthetic biology. The article explains that before now biotechnology has only attempted to modify already existing living things, taking a gene, for example, from one organism, and splicing it into the DNA of a different organism. This will change soon as a number of companies are racing to create tailor-made organisms to produce everything from chemicals for fabrics to fuel.
Even more exciting, and worrying, is talk likening the nascent industry to the early days of mechanical engineering, when parts like nuts and bolts were standardized so that customized machines could easily be made by snapping parts together. With today’s DNA synthesizers, researchers and soon, perhaps, even the general public, will be able to do the same thing, writing the DNA for customized organisms just as amateur programmers write their own software and using synthesizers to create them in real life out of standardized building blocks. Creative people today routinely compete with each other to create ever more outlandish avatars and creatures on platforms like Second Life. Soon, it seems, they will be able to do the same thing with artificial life forms.
Meanwhile at the University of Florida, researchers have made an artificial brain, consisting of 25,000 living neurons cultured from a rat’s brain. This is enough to constitute a simple neural network that the scientists have trained to do a variety of different tasks, most spectacularly flying a virtual aircraft in a flight simulator under a wide range of simulated weather conditions from blue skies to hurricane-level winds. The primary object of the research is to study how living brain cells work rather than create a biological computer to pilot physical unmanned aircraft, but given the recent rise in the use of UAVs, it doesn’t take a genius to figure out that this is something that the Pentagon would be interested in.
Finally, speaking of the Pentagon, it appears that the laser gunship, long a staple of science-fiction, is now a reality. Boeing has installed a prototype 12,000-pound integrated laser module onto C-130H plane and plans to conduct a series of tests with it, culminating with a demonstration of the weapon in 2008. The weapon can be used for both lethal and less-than-lethal warfare and has the major advantage of being pinpoint precise, thus significantly reducing the risk of collateral damage. Unlike conventional laser-guided bombs and missiles, it can’t be deflected by missile defense systems and, since it travels at the speed of light, takes only a matter of seconds to hit the target once fired. The working assumption of course is that it’s a perfect assassination weapon since you can shoot at any small target you want with ultra-precision even in the middle of a dense urban sprawl with minimal risk of harming civilians.