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How important is time in viral biogeography studies?

Posted by jlgreen on 18 Feb 2008 at 08:36 GMT

How does the time span over which the data were collected influence conclusions about the geographical extent of the observed viral sequences? Is it possible that some gene families appeared to be ubiquitous because they were sampled at different times of the year, but at any given snapshot in time (or season) those gene families were actually endemic to particular regions? Did the authors perform any analyses to control for time when considering viral geographic patterns?

RE: How important is time in viral biogeography studies?

shanca replied to jlgreen on 26 Feb 2008 at 18:00 GMT

I'm sure temporal factors influence viral community composition, and therefore the viral genes observed, at the sites that were sampled as part of GOS. I agree that very different patterns may have emerged if we conducted a time series experiment. One of the goals of the project was to perform an inital global survey of microbial diversity; therefore in-depth examination of sites over a specified time-scale were not included as part of this particular study. We have had the opportunity to re-sample certain locations since the completion of the expedition and look forward to comparing the data from these to the original samples.