To those who are new to my web log, thanks for checking it out. To those who have come from my old site, thanks for clicking through.
Continue reading “A (Re) Introduction, Complete With Rams, Plagues, and Chimps”
Category: Blog
In a post last month, I pointed out how aerospace engineers can learn a lotfrom looking at the fossils of ancient flying reptiles. Today’s issue of Nature contains a variation on that theme: ancient swimming reptiles can teach geneticists a lot as well.
Craig Venter has followed up on his announcement that he and his coworkers have assembled a virus from its genome sequence. Now there’s a paper available at the Proceeding of the National Academy of Science web site. A bleary-eyed late-night inspection suggests that this is not a flawless Xerox machine for viruses; the researchers had to cast away lots of misassembled versions. (Still, they were able to isolate a perfect sequence in just two weeks.) More interestingly, the authors talk a bit about how they can use this same method to cobble together chunks of much bigger genomes to make synthetic microbes. That’s when things will get really interesting.
Continue reading “Venter’s Virus–Assembly Instructions Now On-Line”
Two decades ago, a neuroscientist named Benjamin Libet published a classic experiment on conscious will. He had his subjects rest a finger on a button as they stared at a specially designed clock. It had only one hand, which swept through a revolution once every 2.5 seconds. Libet would ask his subjects to push the button at their own choosing. In some runs, he asked them to note the position of the clock hand when they actually pushed the button. In other runs they had to note its position when they first began to think about pushing it.
Futurepundit has an interesting post based on a new paper about so-called junk DNA. Only 2% or so of the human genome actually encodes protein sequences. The rest is a grab-bag of broken genes and virus-like sequences called mobile elements that hijack the cell’s DNA copying-machinery from time to time and insert new copies of themselves back into the genome. A pair of scientists have come up with some ideas about why organisms like us have junk-rich genomes, while bacteria have barely any. I was going to post on it until pre-Thanksgiving business overwhelmed me.