Thursday, January 23, 2014

Has John Brockman's stable lost its edge?

John Brockman is a famous literary agent. Over the years he has assembled a group of intellectuals, and people who aspire to be intellectuals. Every year they publish short articles on the question of the year at the Edge. Here's this year's question: annual question.
Science advances by discovering new things and developing new ideas. Few truly new ideas are developed without abandoning old ones first. As theoretical physicist Max Planck (1858-1947) noted, "A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die, and a new generation grows up that is familiar with it." In other words, science advances by a series of funerals. Why wait that long?


Ideas change, and the times we live in change. Perhaps the biggest change today is the rate of change. What established scientific idea is ready to be moved aside so that science can advance?
There was a time—about a decade ago—when reading the answers to the question was exciting and stimulating.

Jerry Coyne picks two answers that deal with evolution: The Edge question: two bad answers about evolution. Roger Highfield's answer to the question of what idea should be retired is "Evolution is true." Kevin Kelly thinks that the idea of "Fully random mutations" should be tossed in the scrap heap of history.

Jerry shows us why these guys are not intellectuals. Read his blog post.

Lest you think that Jerry found the only bad examples, let me point out another one. Athena Vouloumanos is a psychologist at New York University. The idea that she wants to retire is "Natural Selection is the Only Engine of Evolution." Excellent, I thought, at last somebody has a good answer. Alas, here's what she says ...
Epigenetic control of gene expression contributes to cells in a single organism (which share the same DNA sequence) developing differently into e.g. heart cells or neurons. But the last decade has shown actual evidence–and possible mechanisms–for how the environment and the organism's behavior in it might cause heritable changes in gene expression (with no change in the DNA sequence) that are passed onto offspring. In recent years, we have seen evidence of epigenetic inheritance across a wide range of morphological, metabolic, and even behavioral traits.

The intergenerational transmission of acquired traits is making a comeback as a potential mechanism of evolution. It also opens up the interesting possibility that better diet, exercise, and education which we thought couldn't affect the next generation–except with luck through good example–actually could.
If I had to give a reason why natural selection is not the only engine of evolution I would have picked something very different—something that's been around, and proven, for decades. Epigenetics requires DNA sequences and proteins and if epigenetic modification of a specific DNA site provides a selective advantage under some circumstances then that's natural selection in action.