This is a picture of the brown recluse spider. It has a really nasty bite so it is just as well that it is reclusive.

Below is a gross out photo of the results of a typical bite.

What makes the bite of this spider interesting to The Green Man is the toxin that it contains, called sphingomyelinase (SMaseD) and what makes SMaseD interesting that exists only in two places in nature, the brown recluse spider and the bacterial strains of pathogenic Corynebacteria that cause various illnesses in farm animals.

As the monk Gegor Mendle discovered all those years ago vertical transmission of genes from one generation to its offspring is an everyday process. Lateral gene transfer between unrelated species is a much rarer and special event. This is what appears to have happened in this case however at this stage it is uncertain whether the spider or the bacteria first had the gene for the production of this toxin and the transmission method is still unclear however an obliging virus is probably the most likely candidate. Matthew H. J. Cordes of Department of Biochemistry and Molecular Biophysics, University of Arizona Tucson and Greta J. Binford of Department of Biology, Lewis and Clark College Portland continue the hunt for the origins and transmission vehicle.