Variation in Seed Size Within a Crop of a Costa Rican Mucuna Andreana (Leguminosae)

The mature viable seeds within the seed crop of one individual of Costa Rican Mucuna andreana varied in fresh weight from 2.6 to 9.4 g (average of 6.81 g, s.d. = 1.09 g, n = 282). The seed coats weighed 14 to 17 percent of the fresh seed weight and variation in their weight was not the cause of the variation in seed weight. There was no significant difference in average seed weight of seeds from pods with 1 to 5 filled seeds. The great range of seed weights within one plant's seed crop is interpreted as possibly of adaptive significance in generating a more homogeneous seed shadow than would be the case with a narrow range of seed weights.