Large seeds take the advantage in stressful conditions
It is generally believed that, when competing for the same resources, large plant seeds beat out small seeds regardless of the growing conditions. But according to researchers at the Smithsonian Tropical Research Institute, large seeds actually have the advantage in stressful conditions—such as during a drought or in the shade—while small seeds thrive in abundant sun and water.
The study, published in this week’s edition of the Proceedings of the National Academy of Sciences, explains the evolutionary advantages of producing large, tolerant seeds versus a large amount of small seeds. This variation, says the study’s author Helene Muller-Landau, allows species to coexist  in regeneration sites that vary in stressfulness.
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Muller-Landau, H. (2010). The tolerance-fecundity trade-off and the maintenance of diversity in seed size Proceedings of the National Academy of Sciences DOI: 10.1073/pnas.0911637107