Scientist Joseph Torres is providing dispatches from Antarctica, where he's studying the disappearance of the Antarctic silverfish and the resulting effect on other animals. The decline is thought to be due to global warming. Silverfish are like krill in that many animals eat them (see a graphic of the silverfish's role in the food web here). Dr. Torres thinks that the fish are a bellwether for climate change - if silverfish go, other parts of the food web may be next. TampaBay.com has put together a very thorough overview of this issue and you should definitely check out the site.