Why are more plants found near universities? Probably because more botanists are found there, too, according to study.
March 1, 2007
DEARBORN / March 2, 2007---It seems that there are more flowering plants near university campuses than in other places around the country.
Two University of Michigan scholars found that counties with universities in them were far more likely to have more botanical species reported in them than adjacent counties do.
The researchers compared data from more than 30 areas of the country with major universities, measuring the botanical richness of the county housing the university with that of its neighboring counties.
The study, which was published last year in the Journal of Biogeography, was conducted by Daniel E. Moerman, professor emeritus of anthropology at the University of Michigan-Dearborn, and George F. Estabrook, professor of botany at the University of Michigan’s Ann Arbor campus.
“In almost every case, there were more species reported in the university county than in its neighbors,” according to Moerman and Estabrook.
They considered a range of possible explanations, including the notion “that somehow, universities were situated in counties particularly well-endowed with botanical resources.”
The data were drawn from universities across the country, established over more than 200 years, and almost certainly located where they are because of political and economic pressures, which made that explanation unlikely.
Other possible explanations were also considered, including the idea that university communities attract more visitors from other regions who might bring plant material with them, but there were not enough data to make the case.
The explanation preferred by Moerman and Estabrook is that university counties have high species diversity because they have a disproportionate share of botanists, who are likely to pay more attention to the plants in their local environment.
“We provide evidence over a substantial area of the North American continent, suggesting that botanical diversity increases with the presence of botanists, a phenomenon we call the ‘botanist effect,’” according to Moerman and Estabrook.
In one test of their theory, Moerman and Estabrook looked at the data for Michigan’s Cheboygan County, which “does not have a university, but is the site of the University of Michigan Biological Station, where students have taken field biology courses, and collected plants, for a century.”
It turns out that Cheboygan County has more plant species recorded than adjacent counties, and one particular plant, Symphytum asperum Lepichin, is reported in only two Michigan counties, Cheboygan and Washtenaw, the location of the University of Michigan.
The results have wider implications for other sciences, according to Moerman and Estabrook.
“We believe that the principles underlying this rather different case of collection bias may have widespread applicability, and should serve as a cautionary tale for those doing broad-scale comparative research in a number of areas of science, particularly ecology,” they said.
“Ecologists must be aware that numerical data that appear very solid, collected over many decades, may represent not only the qualities of ‘nature’ but also something of the collectors of the data,” according to Moerman and Estabrook. “This situation may exist elsewhere in science and all ecologists should be aware of the issue and attempt to control for it in analysis.”