Did a vivisection of an American cockroach today to view its circulatory system. I also got a great view of its respiratory system–all the silver tubes are its tracheae, which you can trace to its spiracles on some of the abdominal sections. You can also see the muscles that move its legs at the top. Kind of proud of this one, I did a nice job.
Whoa, that’s really neat. I admit I haven’t really read much about insect anatomy, but with the open circulatory system wouldn’t there be a lot less hardware to see than there would be in a vertebrate? What features were you looking at? It looks like the specimen is in liquid too, is that saline or something to keep everything from sticking together?
Looking at the muscles, I wonder if anyone’s ever done a biomechanical analysis on an invertebrate to know what muscles do what and how much force they exert. I know there’ve been some pretty interesting studies like that on birds at least and I think it’s been done for Drosophila flight muscles.
I’m not sure that there’s less hardware, but it’s definitely smaller, and you don’t have a bunch of bones in the way. I was looking at the heart in particular, trying to see the ostia (holes allowing blood flow) moving, which is why it was a vivisection. The roach was anesthetized and it’s in saline solution.
The roach is pinned dorsal side down, so you can see the heart running up and down the midline, though it’s pretty transparent and not obvious like in most vertebrates. There have been studies on the muscles, but I’m into taxonomy, so I don’t have a whole lot of knowledge in that department. I’m sure it’s been investigated with Drosophila, and with flies in general. The mechanisms of flight for various orders of insects has some interesting literature, but I don’t have any links at the moment.
(via entoderek)
