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Showing posts from August, 2017

Diatom of the Month - August 2017: Fragilariforma virescens

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post by David Williams*
Although he never wrote it down, the late Colin Patterson, one time vertebrate palaeontologist at my home from home, the Natural History Museum, London, often said that when confronted with any particular biological specimen, three questions should come into the minds of systematists: What is it? What is it related to? Where does it live?
For me, the first is often a struggle, as wading through books of images can be a tad soul-destroying, especially if the images never quite match what’s in front of you. Start with something easy – that’s what Frank Round told me, a long while ago now. Easy? There’s a lovely book by Archie Carr, A Naturalist in Florida, A Celebration of Eden (1994). In it there’s a key to the fishes of Alachua County, Florida, first published in 1941. One instruction reads: “Not as above; fins with dangerous spines; catfish-like—in fact, a catfish”, with a footnote: “Any damned fool knows a catfish”. So, Frank suggested Fragilaria virescens1 be…

Alpha

One of the most frustrating things I have seen as a graduate student was a p-value of 0.06. In fact, I have seen this terrible number on more than one occasion. A p-value of 0.06 means that there is a six percent chance that the results I observed were a result of random chance if there really was no effect. Now, I personally think, when it comes to ecology at least, that six percent is low. Think about all the troubleshooting ecological research requires or how we are often limited to small sample sizes. How different is six percent really from 5 percent?
I am not the only one who is suspicious of the alpha values. I have listened to professors proclaim the death of traditional statistics and the end of an era of α < 0.05. Ecologists are moving towards Bayesian statistics. If you have been around FIU long enough you may remember the prestigious Glaser Seminar speaker in 2014 was Dr. David Anderson.
The other day I was surprised to see an article that was advocating for lowering al…

Why Should We All Care About Frozen Mud?

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Post by: Peter Regier
I was recently fortunate enough to get an opportunity through the CUAHSI Pathfinder fellowship to conduct research in Alaska as an extension of my work with the FCE-LTER.The Pathfinder is designed to support new experiences for students working primarily in one field or one location.My project is a cross-LTER collaboration between the FCE site in Florida and the Bonanza Creek (BNZ) LTER site in interior Alaska.I’m using water quality sensors that measure the chemistry of small streams, including the concentrations of dissolved organic carbon (DOC), nitrate, and other water quality parameters.The sensors look like this:

We are using sensors to look at differences in water chemistry in streams spanning a gradient of permafrost coverage.Permafrost is ground that stays frozen year-round, and is a globally important sink of carbon.The permafrost in the region where I’m working is discontinuous, and has “drunken forests” of black spruce that grow at strange angles as t…