Well, it's happened again, what with all the natural history, all the biological diversity, all the talk of experiments and data, all the cool observations and encounters, early morning or late nights in the rain forest, and kilometers of hiking, another fine field trip is shot to heck.
This year's class have been about as good as a group of biology majors gets, and the Phactor has not acquired any new gray hairs from their behavior. He is worn out simply because when you're on educational call more or less around the clock, there is not enough (2 instructors, 18 students) to go around.
So here's one more bit of rainforest natural history. Late November is near the end of the rainy season, and it's been wet, oh not anywhere near a record year (over 470 mm rain in 10 days), but sufficiently wet to keep the amphibians active and happy. One of the neatest little fellows is the levi frog (Dendrobates) so called because of their blue legs. Most of the frogs with which you are familiar are cryptically colored, but these stand out vividly. And their call is very loud, especially for their size (less than 2 cm long), sort of inviting you to find them. But this is a poison arrow frog, and the coloring is there to train any potential predators that this froggy will make you as sick as a dog. This is an example of aposomatic coloring where organisms use bright and vivid patterns to advertise their distastefulness. This one has actually just deposited a tadpole that they were carrying on their back into a little pond of water in a tank bromeliad.
Now to pack and return to early winter, the end of the semeser, and finals in Lincolnland. Blah!
Does expression of the toxA operon depend on ToxT as well as ToxA?
2 days ago in RRResearch