Published online by Cambridge University Press: 26 February 2011
The seed shell of Mezzettia parviflora (Annonaceae), an understory tree from the lowland tropical rain forest of Malaysia, has an extraordinarily sophisticated structure. The shell is entirely made of sclerenchyma (mechanical support tissue) that is in all parts equally dense (about 95% of volume occupied by cell wall). Yet, differences in cell shape and orientation have a strong influence on fracture resistance. The structure appears designed to allow the seed to open for germination, but to limit predation by large animals.