The latest issue of SEED magazine has a quotation from Sir Paul Nurse, winner of the Nobel Prize in Physiology & Medicine in 2001 for his work on the cell cycle in yeast. Here's the quotation ...The complexity of living organisms means that the explanations toward which we endeavor may be non-intuitive. The infrastructure may often not be reducible to simple linear pathways of causal events. More likely, they will form interweaving networks with elements of feedback and feedforward, negative and positive loops, redundant steps, and storage devices that operate on many levels simultaneously. Unlike man-made machines, the architecture of the information will change in time and space to generate the richness of emergent behaviors that distinguish the chemistry of living systems from those of non-living ones.Sounds a bit like vitalism, don't you think? Is he saying that cells don't obey the known laws of physics and chemistry?
Biology may therefore have to become "more strange" if it is to succeed in describing life. To accomplish this, we will need the assistance of those whose discipline underwent its own transformation to become more strange in the early 2oth century, the physical scientists.
Does this mean that those of us who are biochemists and molecular biologists won't be able to figure out how life works unless we call for help from chemists and physicists? What's the evidence for that?
Does he mean that our fundamental understanding of biochemistry is flawed and we need a whole new way of thinking similar to the quantum mechanics revolution in physics? If so, what exactly are those strange things that demand a new way of thinking? I don't see them.
Yes, biology is complicated. Nobody said it was going to be easy. But as far as I can see it's only complicated because of multiple layers of complexity each of which can be fairly simple and each of which obeys the laws of physics and chemistry. There's nothing "strange" going on that I can see. Am I missing something?
[Photo Credit: Eighth annual Women & Science Lecture and Luncheon
at The Rockefeller University]
11 comments :
Maybe he's saying biology is right now along the lines of examining components more than circuits? That there is another layer of complexity and organization and development on top of fitness etc.
He may be thinking about how of late physics and chemistry are catching onto systems thinking. However I am not sure though that physics and chemistry can lead biology in systems thinking. Actually, I think that systems thinking in biology is more likely to discover certain systemic principles, because of the nature of organims as compared to simpler physico-chemical systems.
I don't think he menas that the cell does not obey tha laws of chemsitry and physics. It always does
The truth is more that physics and chemistry are insufficient to explain the cell.
Similarly a car will always obey the laws of physics and chemsitry, but you need to contemplate the organization, the interactions among components and how they are integrated into a whole, to be understand how does a car work.
I think he's saying that nonlinear dynamics (chaos) is a component of life.
I don't think he's saying the cell is incomprehensible. I think he's just saying that we may need nonlinear and unconventional math to accurately model the behavior of genes and molecules inside the cell.
The need for help from mathematicians and physicists would be particularly important if we need to develop new mathematical models - if the math that has worked for modeling relatively simplistic systems like planetary orbits and the atom is not sophisticated enough for the interior of the cell.
This has been productive in the past - it was an influx of physicists and chemists flocking to biology that helped us find the gene back in the day.
Are you missing something? You bet:.
Just flow Sir Paul's text into a x by y rectangle missing out spaces. Then, starting at the place where there is a deliberate mistake (that is, 2oth instead of 20th), you select every nth letter and out pops a comprehensible message, just like the Bible code.
What you’ve got to realize Larry is that Sir Paul's text, like the ideas he alludes to, has all sorts of levels of complexity in it that you'd never guess unless you are suitably primed. The chief primer is Paul’s text itself, which gives us a big clue when he talks about operating on many levels simultaneously! He thereby achieves a subtle self-description and includes a feedback loop to boot in this incredibly clever piece of writing. The man’s obviously a genius and if I meet him I’ll make sure I address him as ‘Sir’. I advise you to do the same.
The complexity of living organisms means that the explanations toward which we endeavor may be non-intuitive.
Sir Paul, what's happened to your English. That should have been towards.
What does this quotation mean - bollocks - that's all. Why does he have to think that finding feedback/forward loops etc., raises deeper questions? Dash it - these are all possible only because that's how physical laws say it should work. Enclose a bowl of water with some plastic bubble, and leave it out in the sun, you will have a feedback loop. Study the phenomenon in depth, uncover new ways of looking at systems, by all means. But don't gab like a wonderstruck newbie. If physics and chemistry are insufficient to explain the cell then change "physics" and "chemistry". It's as simple as that.
I agree with Bayman. The underlying mechanism that these systems develop from, evolution, is characterized by causal pathways. But the behavior of networks such as regulatory systems, the immune system or the nerve system can in principle be awfully hard to describe the detailed behavior in. If that is the goal.
For one thing, these processes show phenomena on separate timescales, and that is a problem in math models. For another, even if we can in principle separate out mildly nonlinear processes in networks by techniques such as s-matrixes, it is quite an undertaking to probe and characterize each component. (And if some nodes are inaccessible the difficulty mounts.)
And of course this is still in the domain of physics, chemistry or even biology. They just need to borrow or develop new methods. I would bet it will be more of the later, as biology will have its own character.
It seemed to me, at first, that he was advocating that biologists should learnr chemistry and physics to better understand that processes that take place in living beings. However, given that biologists already did that a long time ago, with great success, the real meaning of his words is likely to be more subtle...
Sir Paul's comment appears content free to me, however it does appear that quantum computing will need to be added to the biologist's tool kit--at least for photosynthesis http://www.sciam.com/article.cfm?articleID=ED1D1446-E7F2-99DF-3CBF8B2F66C0C5D4&chanID=sa013
I regard this as a revival of the idea that Schrödinger put forward 60 years ago that full analysis of biology would require new laws of physics. This was indeed derided as vitalism (e.g. by Monod), but I think that Monod missed the point. Schrödinger was certainly not saying that the laws of physics are not necessary in biology, only that they (the known laws, anyway) are not sufficient. I'm not aware that anyone has come up with definite evidence either way, or that there are any usable suggestions as to what form the new laws of physics might take, but the suggestion is not absurd.
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