Similarly, the insects' circulatory system is profoundly different from mammals. The insect system consists of a simple tube, the dorsal vessel that runs the length of the body, and pushes the insect's blood into the open body cavity. By contrast, the flow of fluid in mammals occurs in a closed system of tubes, produced by pressure pulsations from the heart.
"Insects pump blood through the heart toward the head, and in some species, reverse the flow toward the abdomen. In this open system, once the blood exits the heart or aorta, it courses around tissues and organs to every part of the insect's body, including the tips of the legs, and somehow returns to the heart," Socha said.
Socha explained why they selected three specific insects to study. They chose the ground beetle since it exhibits rhythmic tracheal compression, the grasshopper because its heart is large and therefore relatively easy to image, and the larvae, pupae, and adults of the silk worm moth. The latter are particularly interesting to the researchers because the larvae and pupae appear to deliver gases primarily by diffusion, whereas the adults have air sacs and exhibit abdominal pumping and convective ventilation.
The researchers also have an educational component as part of the NSF grant. Socha has already appeared on the National Geographic and History channels for his work with flying snakes and insects, and National Geographic has expressed interest in this new endeavor. Socha and his colleagues will also work with primary and secondary school teachers in under-resourced classrooms to develop novel replacement lessons that integrate biology and engineering.
Prior to entering graduate school, Socha joined the national Teach for America program and worked as a high school teacher in Centerville, Louisiana. As the only science teacher in a small rural school at the time, he taught all of
|Contact: Lynn Nystrom|