Here's a local tribute to the Irish - weird, but a tribute

St. Patrick's day celebrations here about has a lot to do with cabin fever. Here in the upper Midwest, people get a bit crazy after a couple of months of winter, and as a result do some pretty weird stuff. Generally this cooped up craziness surfaces just about on the 17th of March, so people do things like this.  What you are looking at is the Chi-town river just a few hundred yards before it flows into Lake Michigan. What the hell is everyone thinking? Who thinks it's a great idea to dye a whole river green? What about the whitefish? TPP must report a chat with a Chi-town fireman whose job, duty perhaps, short straw more likely, was to be prepared to jump into the green river, not just green, but cold and icy too, to rescue any drunken revelers who might fall in. No question about it, he was more worried about the color of the water than its temperature. So what can TPP tell you? People get crazy, and it's just the Irish that deserve the blame, maybe a little, but not the total blame. But at least none of the drinkers who surrounded us fell in, so our loyal public servant did not have to worry about his skin color for the rest of the week. BTW, we Irish prefer a darker shade. 

St. Patrick's Day botanical question

This could be someone having their fun with a jocular, easy-going academic botanist because it's sort of a bit too much of a coincidence for this to arrive in my email box on March 17th.  A "curious student" asks: what happens to an aquatic plant if you put green dye into the water?  Well, that is sort of interesting.  Plants are green because chlorophyll absorbs wavelengths at the red-yellow and blue-purple ends of the spectrum of wavelengths that compose visible light, so the wavelengths transmitted or reflected will be green.  Water dyed with a green pigment will do basically the same thing, so an aquatic plant in green water will get less light to absorb because more of the non-green wavelengths will be absorbed by the water than usual.  Chlorophyll became the photosynthetic pigment of choice because if evolved in an aquatic environment where it absorbs those wavelengths that best penetrate water which is a great filter, and just in case you don't get the connection, land plants have an aquatic ancestry.  And there's gobs of evidence that support that statement.  One demonstration that my students perform is to shine light on a test tube full of some motile algae, usually Chlamydomonas, but the test tube has a black paper sleeve on it with little port holes each covered with a bit of colored cellophane, and one left just open.  The algae have eye-spots and can respond to light, so when you remove the sleeve after a bit, there are bands of green caused by the migration of the algae to those port holes where they have accumulated to get the best light.  So a red cellophane looks red because it absorbs the other wavelengths while red light passes through, and a pretty good band of green will be found next to the red light port hole, and so on.  Now what will happen to an aquatic plant that finds itself in the Chicago River today?  Nothing good! Yeah, if you didn't know this before, they dye the river green. Seriously.