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The Almighty Buck

America's Army Games Cost $33 Million Over 10 Years 192

Responding to a Freedom Of Information Act request, the US government has revealed the operating costs of the America's Army game series over the past decade. The total bill comes to $32.8 million, with yearly costs varying from $1.3 million to $5.6 million. "While operating America's Army 3 does involve ongoing expenses, paying the game's original development team isn't one of them. Days after the game launched in June, representatives with the Army confirmed that ties were severed with the Emeryville, California-based team behind the project, and future development efforts were being consolidated at the America's Army program office at Redstone Arsenal in Alabama. A decade after its initial foray into the world of gaming, the Army doesn't appear to be withdrawing from the industry anytime soon. In denying other aspects of the FOIA request, the Army stated 'disclosure of this information is likely to cause substantial harm to the Department of the Army's competitive position in the gaming industry.'"

Comment Re:hmmm (Score 1) 461

The easy answer: it depends on the environment and its inherent selection pressure.

The better answer: It doesn't matter.

The thing to take away from this experiment is that over the course of 40,000 generations, this population of E. Coli developed mutations which increased its fitness level (as relative to earlier populations). If the selection pressure was higher (up to a certain point, i.e. some bacteria needs to survive the test), the mutation rate would appear faster over your sample time set. If another population was present and was more fit (i.e. "in the wild"), it would have displaced the original population, that's how natural selection works.

Comment Re:Evolutive pressure? (Score 2, Informative) 461

There is a step from "DNA mutation" to "Evolution", and that is adaptation to the medium. Did the mutations change the fenotype (the external aspect/behaviour) to something more adapted? Were set certains goals (for example, putting them in a medium less than ideal for the original strain, but to which its survivors have adapted) or the surviving changes did not affect at all at the species?

I think what you're trying to ask is: "Was the selective pressure determined to be in response to stimuli versus a random occurance?"

The authors cover the difference between neutral drift and selective mutations which increase fitness throughout the paper.

Specifically in answer to your question, though, is the following from the expanded methods & materials:

"We performed Luria–Delbrück fluctuation tests33 to confirm that the Ara-1 population evolved an elevated mutation rate. Bacteria were revived from frozen stocks by growth overnight in LB medium. After dilution and 24 h of re-growth in Davis minimal medium supplemented with 25 mg l-1 glucose, we inoculated 24 replicate 10-ml cultures of Davis minimal medium with 250 mg l-1 glucose with 100–1,000 cells. After 24 h of growth to stationary phase, these cultures were concentrated by centrifugation and plated on LB agar containing 20 mug ml-1 nalidixic acid."

Comment Significance? (Score 1) 461

While I find some of the reported observations very thought-provoking, I have trouble attaching overwhelming significance to this study due to the way the data is presented. For example, 26 SNPs in the 20k-generational line are non-synonymous. On the surface, I find that a significant departure from the norm, but when you account for 12 total populations and the dataset consisting of only one population, something just feels a bit off.

Now, the authors may really be on to something here, they do raise quite a few questions in my mind (and as I re-read the paper, i'll probably answer some and generate more), so time (and further experimentation) will certainly expand this discussion.

Comment Re:Wow... (Score 1) 152

On the surface, it is very easy to attribute the complexity produced by natural selection as a non-random or directed process. Unfortunately, if you look at the number of failures which were required to come up with this arrangement (and the subsequent spread of the most fit type), it's still just as random as any other natural mutation process.

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