Letters to a Young Scientist Read Online Free PDF Page A

organism, or chemical compound, or elementary particle, or physical process, to answer questions about its properties and roles in nature. Such is the predominant research activity in the physical sciences and molecular biology.
    The following example is a fictitious scenario of the first strategy, but, I promise you, is close to true dramas that occur in laboratories:
    Think of a small group of white-coated men and women in a laboratory—early one afternoon, let us say—watching the readout on a digital monitor. That morning, before setting up the experiment, they were in a nearby conference room, conferring, occasionally taking turns at the blackboard to make an argument. With coffee break, lunch, a few jokes, they decide to try this or that. If the data in the readout are as expected, that will be very interesting, a real lead. “It would be what we’re looking for,” the team leader says. And it is! The object of the search is the role of a new hormone in the mammalian body. First, though, the team leader says, “Let’s break out some champagne. Tonight, we’ll all have dinner at a decent restaurant and start talking about what comes next.”
    In biology, the first, problem-oriented strategy (for every problem, an ideal organism) has resulted in a heavy emphasis on several dozen “model species.” When in your studies you take up the molecular basis of heredity you will learn a great deal that came from a bacterium living in the human gut, E. coli (condensed from its full scientific name, Escherichia coli ). For the organization of cells in the nervous system, there is inspiration from the roundworm C. elegans ( Caenorhabditis elegans ). And for genetics and embryonic development, you will become familiar with fruitflies of the iconic genus Drosophila . This is, of course, as it should be. Better to know one thing in depth rather than a dozen things at their surface only.
    Still, keep in mind that during the next few decades there will be at most only a few hundred model species, out of close to two million other species known to science by scarcely more than a brief diagnosis and a Latinized name. Although the latter multitude tend to possess most of the same basic processes discovered in the model species, they further display among them an immense array of idiosyncratic traits in anatomy, physiology, and behavior. Think, in one sweep of your mind, first of a smallpox virus, then of all you know about it. Then the same for an amoeba, and then on to a maple tree, blue whale, monarch butterfly, tiger shark, and human being. The point is that each such species is a world unto itself, with a unique biology and place in an ecosystem, and, not least, an evolutionary history thousands to millions of years old.
    When a biologist studies a group of species, ranging anywhere from, say, elephants with three living species to ants with fourteen thousand species, he or she typically aims to learn everything possible over a wide range of biological phenomena. Most researchers working this way, following the second strategy of research, are properly called scientific naturalists. They love the organisms they study for their own sake. They enjoy studying creatures in the field, under natural conditions. They will tell you, correctly, that there is infinite detail and beauty even in those that people at first find least attractive—slime molds, for example, dung beetles, cobweb spiders, and pit vipers. Their joy is in finding something new, the more surprising the better. They are the ecologists, taxonomists, and biogeographers. Here is a scenario of a kind I have personally experienced many times:
    Think of two biologists hunting in a rain forest, packing heavy collecting equipment, with an online field guide waiting back at camp and DNA analysis at the home laboratory. “Good God, what is that?” one says, pointing to a small, strangely shaped, brilliantly colored animal plastered onto the underside of a palm leaf. “I