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Seed shape

Formal name:  seed shape
Local identifier:  TOP114
Definition:  the variance of the three linear dimensions seed length (TOP:seed length), seed width (TOP:seed width) and seed thickness (TOP:seed thickness) of a seed (PO:seed) dividing each dimension by seed length so that length is unity
Formal Unit:  unitless (variance)

Reference:  K. Thompson, S. R. Band, and J. G. Hodgson, _Seed size and shape predict persistence in soil,? Functional Ecology, vol. 7, no. 2, pp. 236_241, 1993