Dispersal by Explosive Mechanism (Autochory)

Autochory is dispersal in which the fruit itself supplies the dispersing force — no external wind, water or animal carrier is needed, since the fruit's own tissues generate enough mechanical energy to fling the seeds away. This happens in several distinct ways. In some plants, the mere touch of the ripened fruit is enough to trigger a sudden, forceful explosion that throws the seeds well clear of the parent (e.g. Impatiens/Balsam, Hura). In others, contact with water — particularly the first shower of monsoon rain — triggers a sudden, noisy burst that scatters the seeds (e.g. Ruellia, Crossandra). Some plants instead rely on a build-up of internal pressure: as the fruit matures, the tissue surrounding the seeds converts into a mucilaginous fluid, and the resulting high turgor pressure inside eventually ruptures the fruit and ejects the seeds (this same turgor-driven mechanism is seen dramatically in the squirting cucumber, Ecballium elatrium, whose fruit detaches explosively at the slightest touch). Certain long pods build up mechanical tension as they dry and eventually explode with a loud, cracker-like noise, scattering seeds in every direction (e.g. Bauhinia vahlii, the camel's-foot climber). Note on the source text: the printed chapter labels this Autochory section '6.4.3' — the same number already used for the Zoochory section immediately befor …