research papers. Rittschof 

 found the molecule that oyster 

 drills respond to in the 

 chemical "body odor" that 

 oysters and barnacles produce. 

 Amazingly, it is the same kind 

 of molecule that tells hermit 

 crabs a new shell is available. 



"Evolutionarily, these are 

 really old molecules and really 

 old chemical-reception 

 systems," says Rittschof. His 

 research points to the ancient 

 development of systems of 

 chemical communication — 

 perhaps so ancient that it 

 predates the evolution of 

 multicellular organisms. "A 

 molecule in human blood tells 

 all the white blood cells to 

 creep to the site of a wound. ... 

 The same kind of molecule 

 tells hermit crabs that a shell is 

 available." And it tells crabs to 

 release their larvae, barnacle 

 and oyster larvae to settle out 

 of the water column, and 

 oyster drills that they have 

 found their lunch. 



Because the molecules and the 

 chemical communication systems that 

 perceive them are so old, the systems are 

 the same from animal to animal. "You 

 can't modify the transduction system, but 

 you can shape it to different ends," says 

 Rittschof. Animals read different pieces of 

 the same molecule and perform different 

 behaviors as a result, but the medium for 

 receiving and processing the chemical 

 message — the hard-wired reception 

 system — is always the same. 



Rittschof s work with the chemistry 

 of animal behavior brought him to Duke in 

 1982, where he was hired to develop a 

 non-toxic anti-fouling compound based on 

 extracts from soft corals. Existing anti- 

 fouling paints use copper to prevent 

 barnacle growth, but copper is a bio-active 



'DR. DAN" PONDERS THE COMPEXITY OF NATURE. 



element that can be toxic in the marine 

 environment. 



Rittschof eventually received seven 

 patents based on his anti-foulant work, but 

 mass production of the products he 

 developed is on hold. "Registering the 

 compounds would take about 10 years 

 and cost about $1 1 million," he explains. 



So now he is once again concentrat- 

 ing on chemical sensory systems, isolating 

 the bio-active enzymes in fish mucus that 

 tell blue crab larvae and other small prey 

 that a predator is near. With fellow 

 researchers Richard Forward Jr. of Duke 

 and Richard Tankersley of the Florida 

 Institute of Technology, he also has 

 received funds from the National Science 

 Foundation to study how the dynamics 

 and "smell" of estuaries influence the blue 

 crab larvae who settle there. 



In unlocking the secrets 

 of blue crab settlement and 

 fish "body odor," as well as 

 developing anti-fouling paint 

 and better fish lures, Rittschof 

 bridges a long-standing 

 chasm in modem science. 

 "There are two kinds of 

 science," he says. "Science 

 that asks how things work, 

 and science that applies 

 knowledge in practical ways." 

 Rittschof does both. 



His office is a testimo- 

 nial to his wide-ranging 

 interests, and to his respect for 

 both practical and "pure" 

 science. On a crowded 

 bookshelf behind his chair 

 stands one of his patent 

 certificates. Another shelf is 

 dedicated to fossils he has 

 collected, including sharks' 

 teeth, a martin's bill, sand 

 dollars and a horse's molar. 

 Chemical diagrams are 

 scrawled on a blackboard 

 beside his desk. 

 Walls and bulletin boards flutter with 

 photographs and mementoes from students 

 — a snapshot of "Dr. Dan" flanked by 

 grinning coeds, a huge Chinese scroll that 

 he insists reads "Don't worry, be happy," 

 an inscrutable paper oval above his 

 computer that says, simply, "Bacon." 

 "People bring stuff in here and leave it," 

 Rittschof says with a bemused smile. And 

 he keeps it all: paintings and prints, an 

 embroidered cat, an Italian "candy" made 

 of glass. 



Beyond the window lies his cherished 

 estuary, with all its animals and their 

 particular chemistries. Inside is the 

 cluttered habitat Rittschof has created for 

 himself, full of reminders of the work he 

 loves. 



"It's all about teaching and curiosity," 

 he says. □ 



22 AUTUMN 1999 



