New findings from Queen’s University biologists show that in the plant world, bigger isn’t necessarily better. “Until now most of the thinking has suggested that to be a good competitor in the forest, you have to be a big plant,” says Queen’s Biology professor Lonnie Aarssen. “But our research shows it’s virtually the other way around.” Previous studies showed that larger plant species monopolize(垄断) sunlight, water and other resources, limiting the number of smaller plant species that can exist around them. But the research has proved that this is not generally the case in natural vegetation. In the Queen’s project, PhD student Laura Keating targeted the largest “host plants” of 16 woody plant species growing in the Okanogan Valley, British Columbia. The research team calculated the number and variety of plants that neighbored each large host plant. They then randomly selected plots without host plants and calculated the plant species there as well. The research showed that the massive trees have no effect on the number of species with which they coexist. Smaller plants have many advantages over their overbearing neighbors, Professor Aarssen notes. Larger species generate physical space niches under their shelters where smaller species grow well. Smaller plants are much more effective than large trees at using available resources. They also produce seeds at a much younger age and higher rate than their bigger counterparts, and settle down much more quickly—thuscompeting with the newly-born plants of larger species. 小题1: What’s the main idea of the text?
a. Randomly selected plots without host plants and-calculated the plant species. b. Calculated the number and variety of plants that neighbored each large host plant. c. Selected the largest individuals or "host plants" of 16 woody plant species.
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