"So, naturalists observe, a flea has smaller fleas that on him prey; and these have smaller still to bite ’em; and so proceed ad infinitum."
- Jonathan Swift
February 12, 2010
February 12 - Nosema bombycis
Busy little Bombyx mori caterpillers happily crunch up mulberry leaves and spin cocoons where they will pupate and transform into moths. These cocoons are made of silk fibers that are harvested and processed to produce silk - in fact, 70 million pounds of silk, every year. But, of course, like virtually all creatures on the planet, silkworms suffer from parasites, too. One of the best known is Nosema bombycis, a microsproridian parasite, that causes a disease known as pébrine - so called because it produces pepper-like spots on the caterpillars. The disease is highly infectious and can pass from mother moth to her eggs, so it has long been a major concern for silkworm breeders. Louis Pasteur, the famous French microbiologist discovered that infectious agents were causing the disease in silkworms and is credited for saving the industry at the time. Microsproridia are a very diverse group of spore-forming unicellular parasites, many of which infect insects. They were once thought to be primitive eukaryotes, but they are now thought to be more closely related to fungi.
Image from this website.