Wednesday, January 15, 2003
Have you ever watched a mosquito liberate itself from its pupal case at the surface of the water "by a dorsal splitting of the pupal integument"?
I thought not.
The fancy part of that question, by the way, is lifted almost verbatim from the wonderful Freshwater Invertebrates of the United States, 2nd Ed., by Robert W. Pennak. My bible.
To go on--I have. And under what I think were remarkable circumstances. It was 1991. I had stopped at my alma mater's bio lab to study up on aquatic invertebrates, on the way to interview for a job I desperately, passionately, wanted. Anyway, after perusing their extensive collection of preserved specimens, I dipped a dollop of water, algae and assorted minute animals out of their aquarium, and put the dish under the dissecting microscope (the one that only magnifies to 4x or so).
To my amazement, there were mosquito larvae in the sample I'd drawn. They were in the pupal stage, with their siphons clinging to the surface tension of the water. They seemed to have white heads, and several were squirming spasmodically. I lost myself watching their jerky exertions.
Then, one of the pupal cases split open, and a mosquito head the size of a pen-tip burst through. It was emerging! Right before my eyes!
I held my breath and watched the creature struggle to free itself from the body of the case. It writhed and snapped, and I urged it on, "You're almost there! Keep trying!" It looked so hard! Such huge effort for such a tiny creature. Then, its narrow tail-end squeezed free, and an adult mosquito stood on the water surface, its hair-thin feet making minute dimples on the water's skin. It spread its damp wings--miniscule stained-glass windows in the microscope's field--and in five seconds it disappeared. Lifted up out of the specimen bowl and vanished into the air of the cavernous lab.
I sat back, stunned. I felt like I'd watched a birth. How could I be so lucky, to take my sample just five or ten minutes before nature told this little individual "Its' time! To fly!" I'll never forget it.
I got the job, too.
If you're thinking, "Cool! Wish I could see that!" you just might be a biologist. If you're thinking "Yeuch! Why didn't she kill it!" then you're not a biologist. I won't hold it against you.