I am sure that in 50 years, we are going to know a lot more about how the mind works. The fusion of psychology and genetics will tell us about how our personality is influenced by our genes, and they’ll also show exactly how the environment plays a hand as well. The preliminary evidence is just too impressive to seriously doubt it. Likewise, I am sure that we will have a deeper understanding how our minds have evolved, pinpointing the changes in DNA over the past six million years have given us brains that work very differently than apes. Again, the first results can’t help but inspire a lot of hope.
Author: admin
The soft spot on a baby’s head may be able to tell us when our ancestors first began to speak.
Evolution works on different scales. In a single day, HIV’s genetic code changes as it adapts to our ever-adapting immune system. Over the course of decades, the virus can make a successful leap from one species to another (from chimpanzees to humans, for example). Over a few thousand years, humans have adapted to agriculture–an adult tolerance to the lactose in milk, for example. Over a couple million years, the brains of our hominid ancestors have nearly doubled. Sometimes scientists distinguish between these scales by calling small-scale change microevolution and large-scale change macroevolution. Creationists have seized on these terms and used them to build one of their central canards: that they accept microevolution but can then reject macroevolution. That’s a bit like accepting microeconomics–how households and firms make decisions and interact in markets–but then denying macroeconomics–how entire societies produce goods, how inflation rises and falls, and so on. Evolutionary biologists debate fiercely about how macroevolutionary change emerges from microevolution. But they continue to find abundant evidence that the two are a package deal.
See you September 13.
Today scientists took another step towards creating the sort of simple life forms that may have been the first inhabitants of Earth. I wrote a feature for the June issue of Discover about this group, led by Jack Szostak at Harvard Medical School. Szostak and his colleagues suspect that life started out not with DNA, RNA, and proteins, but just RNA. This primordial RNA not only carried life’s genetic code, but also assembled new RNA molecules and did other biochemical jobs. Szostak and others have created conditions in their labs under which today’s RNA can evolve into a form able to cary out these primordial tasks. So far, their evolved RNA molecules can assemble short fragments of RNA, using another RNA molecule as a template.