At the April 29 noontime free lecture at the Smithsonian Tropical Research Institute's Tupper Auditorium, the lecture was about liverworts and the scientists argued about methodology.

Dr. Gregorio Dauphin, a German-educated Costa Rican botanist, spent most of his one-hour lecture outlining "70 years of bryology on BCI: the hepatic flora." "Bryology" is the study of bryophytes, a plant group whose members are green and seedless, and mostly lacking in complex tissues. Mosses, hornworts and liverworts are all bryophytes, which reproduce sexually by spores and asexually by pieces breaking off and establishing themselves by anchoring by way of multicellular rhizoids rather than true roots on strata where they can grow. The "hepatics" are the liverworts (sometimes known as "scale mosses"), mostly small macroscopic plants that are distinctive by their oily bodies, elaters and lunularic acid secretions. Like orchids, liverworts are not parasitic to the plants upon which they live.

Liverworts and other bryophytes have been collected on Barro Colorado Island since the late 1920s, with the first scientific publication about them being Dr. Standley's "The Flora of Barro Colorado Island, Panama" in 1933. There have been a number of other studies, several more specifically about the bryophytes, since then. Some of the key findings are that the diversity of species of this type of plants is lower at lower elevations; that light and humidity are key factors in their proliferation; and that when the plants are found growing on leaves, short-lived leaves tend to get more liverworts growing on them than do long-lived leaves.

Dauphin then described his work on the island. He collected 67 species of liverworts, found within 39 genera and 11 families. A little more than three-quarters of the species were of the Lejeuneaceae family, which Dauphin said "is what you'd expect in the lowlands." He noted that the moss families on the island are more evenly distributed than the liverworts. On the island he found mostly liverwort varieties that grow on bark, although there are also species that grow on leaves, rocks, dead logs or in soil.

In his latest study Dauphin marked off 30 little "plots" of 30 square centimeters each on 15 trees, half of the squares on the north sides of the trees, half on the south sides. What he found was that there is denser liverwort growth on the north sides, a fact he attributed to the difference in light.

Then came audience question time, and an argument ensued about whether Dauphin's sampling was random enough to be scientifically useful. For example, it was suggested that on one or two control trees, there should have been many plots up and down the tree to see how elevation --- which would also include a function of light --- might affect the types and numbers of hepatica to be found. "Are you adequately sampling what's on each tree?" Dauphin was asked. The biologist's choice of but one species of tree for his plots was also questioned. Audience members wanted to know about liverworts on different kinds of bark, and how patches on trees close to or far from one another might vary.

Dauphin stuck to his guns about the value of his work, but did admit that some of the suggested samplings would be good subjects for further study. However, some members of the audience left unconvinced whether, absent some more control group studies to test his methodology, his sampling techniques were scientifically valid.

As popular cultural phenomena like Dr. Frankenstein's compulsion to prove his colleagues at the medical society fools allege, frailties of the human ego do make their way into scientific debate. Grants can be lost and careers side-tracked by faulty methodology or the perception thereof. Thus scientific debates can get as heated as political arguments.

However, at the end of the day it's part of science that every researcher's work will be questioned, and that when important observations are made or conclusions reached, sooner or later some other scientist will check his or her colleagues' work by trying to duplicate experiments, or by conducting the control samplings that weren't done in prior experiments. If this were not the case, then scientific fraud would flourish more than it does and the militant ignoramuses of this world would ultimately be given more ammunition for their battles for prejudice and against knowledge. The only reason the Flat Earth Society or the anti-evolutionists haven't won the hearts and minds of most educated people is because scientists tend to ask irritating questions of one another.

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