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Corante Blogs examine, through the eyes of leading observers, analysts, thinkers, and doers, critical themes and memes in technology, business, law, science, and culture.

The Press Will Be Outsourced Before Stopped

Vin Crosbie, on the challenges, financial and otherwise, that newspaper publishers are facing: "The real problem, Mr. Newspaperman, isn't that your content isn't online or isn't online with multimedia. It's your content. Specifically, it's what you report, which stories you publish, and how you publish them to people, who, by the way, have very different individual interests. The problem is the content you're giving them, stupid; not the platform its on."
by Vin Crosbie in Rebuilding Media

Travels In Numerica Deserta

There's a problem in the drug industry that people have recognized for some years, but we're not that much closer to dealing with it than we were then. We keep coming up with these technologies and techniques which seem as if they might be able to help us with some of our nastiest problems - I'm talking about genomics in all its guises, and metabolic profiling, and naturally the various high-throughput screening platforms, and others. But whether these are helping or not (and opinions sure do vary), one thing that they all have in common is that they generate enormous heaps of data.
by Derek Lowe in In the Pipeline

Disrobing the Emperor: The online “user experience” isn't much of one

Now that the Web labor market is saturated and Web design a static profession, it's not surprising that 'user experience' designers and researchers who've spent their careers online are looking for new worlds to conquer. Some are returning to the “old media” as directors and producers. More are now doing offline consulting (service experience design, social policy design, exhibition design, and so on) under the 'user experience' aegis. They argue that the lessons they've learned on the Web can be applied to phenomena in the physical and social worlds. But there are enormous differences...
by Bob Jacobson in Total Experience

Second Life: What are the real numbers?

Clay Shirky, in deconstructing Second Life hype: "Second Life is heading towards two million users. Except it isn’t, really... I suspect Second Life is largely a 'Try Me' virus, where reports of a strange and wonderful new thing draw the masses to log in and try it, but whose ability to retain anything but a fraction of those users is limited. The pattern of a Try Me virus is a rapid spread of first time users, most of whom drop out quickly, with most of the dropouts becoming immune to later use."
by Clay Shirky in Many-to-Many

The democratisation of everything

Over the last few years we've seen old barriers to creativity coming down, one after the other. New technologies and services makes it trivial to publish text, whether by blog or by print-on-demand. Digital photography has democratised a previously expensive hobby. And we're seeing the barriers to movie-making crumble, with affordable high-quality cameras and video hosting provided by YouTube or Google Video and their ilk... Music making has long been easy for anyone to engage in, but technology has made high-quality recording possible without specialised equipment, and the internet has revolutionised distribution, drastically disintermediating the music industry... What's left? Software maybe? Or maybe not."
by Suw Charman in Strange Attractor

RNA Interference: Film at Eleven

Derek Lowe on the news that the Nobel Prize for medicine has gone to Craig Mello and Andrew Fire for their breakthrough work: "RNA interference is probably going to have a long climb before it starts curing many diseases, because many of those problems are even tougher than usual in its case. That doesn't take away from the discovery, though, any more than the complications of off-target effects take away from it when you talk about RNAi's research uses in cell culture. The fact that RNA interference is trickier than it first looked, in vivo or in vitro, is only to be expected. What breakthrough isn't?"
by Derek Lowe in In the Pipeline

PVP and the Honorable Enemy

Andrew Phelps: "Recently my WoW guild has been having a bit of a debate on the merits of Player-vs.-Player (PvP) within Azeroth. My personal opinion on this is that PvP has its merits, and can be incredible fun, but the system within WoW is horridly, horribly broken. It takes into account the concept of the battle, but battle without consequence, without emotive context, and most importantly, without honor..."

From later in the piece: "When I talk about this with people (thus far anyway) I typically get one of two responses, either 'yeah, right on!' or 'hey, it’s war, and war isn’t honorable – grow the hell up'. There is a lot to be said for that argument – but the problem is that war in the real historical world has very different constraints that are utterly absent from fantasized worlds..."
by Andrew Phelps in Got Game

Rats Rule, Right?

Derek Lowe: "So, you're developing a drug candidate. You've settled on what looks like a good compound - it has the activity you want in your mouse model of the disease, it's not too hard to make, and it's not toxic. Everything looks fine. Except. . .one slight problem. Although the compound has good blood levels in the mouse and in the dog, in rats it's terrible. For some reason, it just doesn't get up there. Probably some foul metabolic pathway peculiar to rats (whose innards are adapted, after all, for dealing with every kind of garbage that comes along). So, is this a problem?.."
by Derek Lowe in In the Pipeline

Really BAD customer experience at Albertsons Market

Bob Jacobson, on shopping at his local Albertsons supermarket where he had "one of the worst customer experiences" of his life: "Say what you will about the Safeway chain or the Birkenstock billionaires who charge through the roof for Whole Foods' organic fare, they know how to create shopping environments that create a more pleasurable experience, at its best (as at Whole Foods) quite enjoyable. Even the warehouses like Costco and its smaller counterpart, Smart & Final, do just fine: they have no pretentions, but neither do they dump virtual garbage on the consumer merely to create another trivial revenue stream, all for the sake of promotions in the marketing department..."
by Strange Attractor in Total Experience

The Guardian's "Comment is Free"

Kevin Anderson: "First off, I want to say that I really admire the ambition of the Guardian Unlimited’s Comment is Free. It is one of the boldest statements made by any media company that participation needs to be central to a radical revamp of traditional content strategies... It is, therfore, not hugely surprising to find that Comment is Free is having a few teething troubles..."
by Kevin Anderson in strange
In the Pipeline: Don't miss Derek Lowe's excellent commentary on drug discovery and the pharma industry in general at In the Pipeline

The Loom

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November 12, 2003

Recoil from Dollo's Law

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Posted by Carl Zimmer

Time always marches forward, of course, but does evolution?

It's certainly easy to impose a march of progress on the course of evolution. That's why the sequence of apes transforming into humans as they march from left to right is so universal. Of course, there are also pictures in which Homo sapiens, having risen up to noble, upright proportions, begins to crouch back down again, until he (never a she, I've noticed) is crouching in front of a computer or a television or facing some other ignoble end. As I wrote in Parasite Rex, this anxiety--an anxiety mostly about ourselves and not about nature--led biologists to come up with the concept of degeneration. While most life strove upwards towards more complexity, some backsliders slipped down again. Barnacles (once nimble crustaceans) were a classic example.

If a lineage could degenerate, could it then regenerate--could it recover the complexity its ancestors had lost? In 1893, the French biologist Luois Dollo declared absolutely not. It was too unlikely that evolution could retrace its steps so carefully to restore some lost trait.

Dollo's Law survived the rise of genetics and the modern synthesis of evolutionary biology, albeit it a very altered form. It was no longer an ironclad law, like the laws of physics, but instead a striking pattern that speaks to how evolution works. If a lineage of animals no longer needs some feature--eyes for example--the genes that build eyes gradually mutate, usually into dead pseudogenes. It would be a nearly impossible roll of the dice that would mutate all of those genes precisely back into the form they had before. Whales didn't' re-evolve fish fins, for example, but instead evolved paddles, for example.

To mark the centennial of Dollo's Law, the late Stephen Jay Gould wrote an influential paper in which he used coiled sea shells as evidence of the new and improved Dollo's Law. In some lineages of gastropods, the shell has uncoiled. Gould pointed out that an uncoiled shell allows a gastropods to grow flexibly around obstacles or to reach out towards sources of food. Gould made a careful study one of these groups and argued that none of its member species had ever managed to re-evolve a coiled shell. He suggested that the uncoiled gastropods had become so committed to their new way of life that natural selection could not return them back to their former coiled glory.

Now, on the 110 year anniversay of Dollo's Law, comes a fascinating report that challenges Gould. In a paper published online today in the Proceedings of the Royal Society of London, biologists Rachel Collin and Roberto Cipriani take a look at another group of gastropods--the Calyptraeidae, which includes slipper shell limpets, cup-and-saucer-limpets, and hat shells. Out of 200 species, just a dozen or so are coiled. It used to be thought that the coiled species branched off first, before the common ancestor of the remaining species lost its whorl.

But that's not what shook out when the biologists constructed a family tree for these gastropods by sequencing three different genes in 94 species. They discovered that the gastropods actually re-coiled on at least two separate occasions.

At first this seems hard to swallow. Fossils of these particular shells suggest that they had been uncoiled for anywhere between 20 and 100 million years before re-coiled species arose. How could the genes for coiling have survived all that time? Collin and Cipriani point to a study that came out earlier this year on stick insects. That study showed that some stick insects lost their wings, but that their descendants re-evolved them many times over. These re-coiled limpets may be rare, but they are not flukes.

The answer to these puzzles appears to lie in the genes that assemble these animals. In the case of stick insects, the genes for building wings were probably preserved because they continued to do something else in another part of the body--they built legs. Collins and Cipriani propose a related hypothesis for the shells. The re-coiled gastropods develop directly from eggs, but many other gastropods have distinct stages in their life cycle. As larvae, they develop one type of shell, and then as adults, they develop a completely new shell. Collin and Cipriani envision a lineage losing its coils in its adult shell, but still retaining them as larvae. So the coiling genes were still on active duty for millions of years. Then, in some lineages, these larval coiling genes were borrowed to build coiled adult shells. And finally, through other evolutionary changes, these gastropods lost their larval stage and simply developed uncoiled shells.

So evolution can, it seems, double back on itself sometimes. But only if it tucks away the secrets of the ancestors in a safe place.

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