DNA in a cup of water?

Biodiversity is difficult to measure, especially in aquatic settings. There is a new technique, much like one described in an earlier blog post where scientists tested the DNA found in the soil. In this technique scientists take a water sample from a body of water can find the biodiversity. It's an interesting technique.

What do you think the benefits of this would be? What are some drawbacks? When you're answering, think in terms of the scientific method.

DNA in dirt?

This article identifies that scientists are using the amount of DNA found in the dirt of an area to determine species diversity? How did they determine the accuracy? What are the advantages and drawbacks of this research?

Black Death extinct?

This MSNBC article cites research that states that in doing forensic DNA work on bodies of Black Death victims the strain of Yersinia pestis that caused the Black Death is extinct. The next article identifies that there has been very little evolution in the bacterium.The last article identifies how antibiotics have adjusted our thinking of bacterial pandemics.

What do you think of the research? What errors could there be? What other evidence is there that the strain of Y. pestis that caused Black Death is no longer with us? What would have caused there to be so little evolution in the bacterium? Could the conditions that are cited in the latter articles arise again to cause another pandemic?