February 26, 2016 at 12:17AM

Today I Learned: 1) RNA ladders* are really oddly tricky to use correctly. I'd had some trouble getting mine to work before -- they were coming out as a smear, rather than as nice crisp bands. I figured the ladder must have been contaminated by RNases and ruined, so I went and got a fresh ladder, a fresh set of pipettes, and a whole bunch of RNAse-away. It didn't help. What *did* seem to help was to change the preparation protocol a bit. New England Biolabs, who sells this ladder, recommends heating it either at 90C for 2 minutes or 70C for 10 minutes. I had always previously done the former, but the ladder came out much more nicely when I did the latter. But then I tried it again later in the day and it didn't work... I think maybe I didn't let the second one cool long enough before loading it, but I'm really not sure. * A ladder, in the context of biology, is a standard set of DNA, protein, or, in this case, RNA of known size and composition that can be run alongside experimental samples in an electrophoretic gel. Since you know the sizes of the ladder components, you can use their bands on the gel to determine the sizes of your own samples. 2) There's a virus, called an iridovirus, which infects crickets, and causes them to mate much more frequently (until it kills them). It also happens to sterilize the crickets, presumably so the cricket spends less time laying eggs and more time mating. Oh, and it turns their guts blue. 3) Guess how scientists first discovered that some frogs are venemous? A scientist picked one up and it bit him. The last two facts courtesy of this entertaining NPR article: http://ift.tt/20YAs2S