Today in lab, we made a mixture consisting of Dawn soap, water, and glycerine in order to play with bubbles. Although this was fun, it actually has some application to developmental biology. In fact, many biologists have written books about the math behind soap bubble forms that can be related to cellular architectures (i.e. epithelial sheet or a blastula).
Although it was a lot harder to manipulate the bubbles than I thought, I was able to make some pretty cool formations. The first bubble formation that I was able to make is similar to the blastoderm with the blastocoel and blastoderm layer (see image). Although I was only able to make a few bubbles line up, you can still see how the bubbles attach to the end of another bubble in order to form a lining around the center. However, this is also some asymmetry with the bubbles which was hard to avoid. 
The second bubble formation that I was able to make is a little harder to describe in relation to biology. This bubble formation kind of resembles the gastrulation of the blastula to form the gastrula where the outside layer folds into the center. However, you can see the differences in the last image below of the gastrula. Gastrulation is the process that forms the three germ layers known as the ectoderm, endoderm, and mesoderm. After this stage, the organs will being to develop during organogenesis.
After much struggle, we are finally done with the drosophila development lab. Our assignment was to pick something interesting during drosophila development (i.e. mating to pupae hatching) and record it using a Leica Wild M3C Scope and a PixieLINK camera. My lab partner and I put two flies (male and female) into a small petri dish with a damp KIMTECH wipe around the sides. Although this proved to be troublesome during recording, it allowed a moist environment for the flies to thrive.
Today in class, we reviewed drosophila development and continued with vertebrate development. One of the most interesting concepts that we discussed was the role of maternal and zygotic sources for development. Although we often think that vertebrates (especially mammals and humans) are more 'nurturing' and 'motherly' than invertebrates, such as the fruit fly, our preconceived notions may be false in some manners. 
In class today, we continued to discuss Endless Forms Most Beautiful by Sean B. Carroll. Specifically, we dove into chapters 8 and 9 which pertain to butterfly wing spots and zebra stripes. Although Carroll has received much criticism for focusing so much on these two topics, we discussed why this information might be important and, more importantly to some, why it might be beautiful.
In order to elaborate further on the differentiation of species and organisms within species after the phylotypic stage and its relation to Hox genes, I thought it might be useful to discuss the evolution of wing number and form. In Sean B. Carroll's book, Endless Forms Most Beautiful, he describes this process by using the gill-to-wing theory. The gill-to-wing theory has much evidence that supports the evolution from crustacean gill branches to insect wings. Of course, there are many transitional evolutionary steps that this change required. For example, a mayfly nymph, a primitive winged adult, and a modern lepidopteran all have very different types and numbers of wings. Specifically, the mayfly nymph does not have any wings on T1, whereas the primitive winged adult has reduced T1 structures and no wings on the abdomen.
For our next lab, we will be taking a progressive set of pictures that will be arranged into a movie. The theme: something interesting in drosophila development! I thought it would be helpful to look up the development of drosophila in order to get a better idea of what I want to focus on (all dependent factors aside. i.e. time). I realize that while I might like a certain part of development more than another, it might be near impossible to capture that moment in time. I think it would be interesting to look at the gradual development from a pupa to an adult, giving rise to legs and wings. However, since they encapsulate themselves, it may be impossible to see this transformation. Therefore, I would like to try to see when the adult drosophila emerges from the pupa into a fully formed organism with wings and all. Although it may be hard to identify when the transformed adult will emerge from the pupa, I think I will be able to monitor it enough to get a good idea with the help of Professor Myers. I am hoping that it will look much like the video linked below! 
This is a response/expansion to a post written about 
Learning about genes, proteins, switches, 'genetic tool kits,' and the like has been particularly interesting. However, the part of this course that has been distinctively exciting is how these aspect of development are connected to evolution. As described in Endless Forms Most Beautiful by Sean B. Carroll, wing development sheds some light on powerful evidence of evolutionary development. From gills to wings, a few proteins have been identified as necessary components for this type of development. Specifically, Apterous and Nubbin have been found to be selectively expressed in areas where wing and gill development take place (i.e. the respiratory lobe in crustaceans). 
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