…and forever after, you’re the guy who wrote that Dinosaurs in Space paper. It’s gotten a certain amount of criticism, plus a spit-take or two.
The paper sounds like it started off reasonably rational. I can’t be sure, because it’s behind a paywall, but most of the commenters commented on this. It talks about chirality, or handedness in the shapes of various life-building chemicals. Life-building amino acids are left-handed (L-)*, not right-handed (D-), but there’s no reason they had to be**, and there’s no reason we couldn’t have a more even mix of the two kinds of handedness.
I suspect, as a simple systems scientist (that is, non-biologist, non-biochemist, non-evolutionist, non-..work your way through the rest of the Standard Occupational Classification System) that what we are seeing is a frozen accident. Life accidentally started out left-handed, and made more left-handed chemicals. Right-handed amino-acids didn’t have such a support group, and got out-competed. That hypothesis turns on the idea that a primitive L-amino based life form would prefer left to right-handed amino acids. It’s testable. (more…)
