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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 21, 2003

The History of An Orange Glow

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Posted by Carl Zimmer

The glow of a beetle has inspired an elegant bit of evolutionary detective work that appears in the Proceedings of the National Academy of Sciences. Americans like myself are familiar with fireflies, but in the tropics the night is also illuminated by beetles. When Darwin came to Brazil on the Beagle, he amused himself by noting how the beetles were "rendered more brilliant by irritation." Naturalists have gotten a bit more sophisticated at studying beetles since then. They now know that the male beetles use the light organs on their underside to get the attention of females that are sitting in the trees and bushes; when the female sees a glow she likes, she registers her approval by flashing light organs on her back. (Fireflies do the same thing, but while they flash, the beetles give off a steady glow.) Scientists also know how the glow is made--a gene creates a protein called luciferase, which cuts up another protein called luciferin, releasing photons at a distinctive frequency. Depending on the species, the frequency is different.

The authors of the PNAS were attracted to the glow of one beetle in particular: a species that lives on Jamaica, Pyrophorus. plagiophthalmus. This species is peculiar, because its males can glow in a wide range of colors, from green to orange. Why so many colors? It's all too easy to say, "Well, natural selection made it that way," and leave matters at that. In fact, it's possible that natural selection had no immediate role at all. Maybe Jamaica was colonized by a handful of beetles that just so happened to have some rare mutants in their midst, and they all proceeded to breed like crazy. Or perhaps it's the females that have been evolving, and the genes they use for their own light organs also produce light in the males.

The scientists realized that the beetles offered a fabulous opportunity to study adaptation. Thanks to previous generation of beetle-loving scientists, they knew a lot about just about every link in the chain that joins the sequence of a gene to a living, breathing organism. They could even take the gene out of beetles and stick it into bacteria in a petri dish, where the gene would continue to produce light. By tinkering with each nucleotide in the gene, they could see exactly how the light changed as a result.

The scientists found that the colors of the male beetles don't depend on genes shared with the females. Instead, they are the product of three different versions of the same gene (alleles). The alleles produce green, yellow, and orange light, and since each beetle can carry two copies of the gene, they can make various colors. The scientists then reconstructed the evolutionary history of the gene, by comparing the alleles to genes from beetles on neighboring islands. It turns out that the green allele is the oldest. It's likely that the first colonists of Jamaica all glowed green. Then, with a few changes to the gene's sequence, a new version emerged that produced yellow light. And then most recently, an orange gene emerged. In other words, the glow has steadily been shifting down through the spectrum towards the red end.

And the shift, the researchers showed, has taken place thanks to natural selection. Scientists can detect natural selection in DNA in several ways, one of which is to compare the number of differences between genes that lead to changes in their respective proteins to differences that cause no change. If the protein-changing mutations are significantly more common than the silent ones, natural selection must be at work.

The scientists don't actually know why the beetles are turning orange. It may be, for example, that birds showed up on the island that have a harder time spotting orange beetles than green ones. Or maybe some extinct beetle also glowed green, leading to dead-end interbreeding for females who picked the wrong species. Whatever the answer, the scientists have shown that there is an answer out there beyond the random flux of wandering beetles. Now the scientists have to go out and find the last links in this evolutionary chain.

CORRECTION 11/21/03 1 PM: Thanks to Dough Gladstone for pointing out that fireflies are also beetles. Still, my childhood would have been subtly yet significantly different if I had spent it watching unblinking glows at night instead of the lazy winks of lightning bugs.

Comments (4) | Category: Evolution


COMMENTS

1. Ethan Fremen on December 13, 2003 11:04 PM writes...

Isn't another ready candidate for the selective pressure sexual selection? Maybe the ladies just like orange...

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2. Carl Zimmer on December 13, 2003 11:20 PM writes...

Perhaps, but why are their tastes changing so steadily from green on this one island?

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3. Sebastian Velez on February 24, 2004 04:52 PM writes...

I'm one of the PNAS paper authors. That female click beetles are choosing orange over green canditates is our main hypothesis. There are several lines of evidence pointing to a role of sexual selection. In other bioluminescent insects (eg. fireflies), adult bioluminescence is exclusively used for sexual signaling. Also, we only catch males flying and females on the ground and both sexes glow for only half an hour at dusk. We have a few experiments designed to test for sexual selection. We'll see!

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4. P G Jonsson on March 20, 2004 11:06 AM writes...

I spotted some red emitting insects in Sweden back in 1986, and got them on film. It looks like a new species, maybe a variation of Pyrophorus. No sample was collected, however.

More info at my homepage
www.newinsect.com

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