Dr. Purves’ Groodies
The Story of Groodies…
Groodies were introduced at Harvey Mudd by Bill Purves, the founding father of the HMC Bio Department. The Biology 52 Homework Book from 1980 is subtitled 鈥淭ales of Groodies, Raging Elephants, and Noble Cucumbers鈥, and the opening sentence is, 鈥淲elcome to the wonderful world of Groodies鈥.
The first Groody homework problem in Bio 52 began:
While traveling with HMC鈥檚 Bates Time-Warp Program, you find yourself stranded in a far-off galaxy, a long time ago. To pass the time you pop open a can of Schlitz — and are dismayed when two (2) tiny creatures leap into the beer. Faster than you can imagine, 32 similar creatures climb out of the beer and shake themselves dry. Over the next several weeks you learn many things about these Groodies. (You suspect that they are called Groodies because each one wears a T-shirt with 鈥淕roody鈥 written on it in microscopic letters.) Groodies are the dominant local life form; their principal activities are the manufacture of T-shirts and of beer. The beer is essential for their reproduction — a couple of Groodies (one of each sex) dive in together and produce 32 progeny . . . .
But the evolutionary origin of Bio 52 Groodies predates even the original Bio 52 Homework Book by about a decade. As Prof. Purves explains in the preface,
A heart-felt acknowledgment: I confess that I did not invent the name 鈥淕roody,鈥 which by the way is pronounced 鈥済rew-dee鈥, NOT 鈥済row-dee鈥. Groodies first appeared in a fine but commercially unappreciated book by Burton Guttman (Biological Principles, W.A. Benjamin, Inc., New York, 1971). On page 136 of that book, Guttman had a bunch of drawings of strange little critters (see figure below), captioned, 鈥淭he little creatures shown here are groodies; they are useful (but unfortunately fictional) little organisms that are pure genetic tools. We will use them in parallel with phage to illustrate the basic concepts . . . .鈥 When I read the preface of Guttman鈥檚 book (just as you are for some unknown reason reading this preface), I learned the ultimate source of the name: 鈥淢y daughter Erica is responsible for the name groodies. . . .鈥

Anyhow, I think my Groodies are handsomer. I thank Dave Gonda, HMC 鈥79, for the original, definitive drawings of Groodies. . . .
The first Bio 52 Groodies only appeared in Mendelian genetics problems, but today we have problems on the molecular biology, biochemistry, and evolution of Groodies as well as classical Groody genetics. Who knows where they鈥檒l show up next!



