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 25 if no dispersers DHJanzen100687.jpg high resolution
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| What if there are no seed dispersers at all? In many cases, the seeds never get out of the fruit, and rot with it. For example, if a Crescentia alata fruit is not broken open, the fruit pulp inside eventually ferments and the fermentation products kill the seeds. The rock-hard dry fruit wall of an indehiscent Hymenaea fruit does eventually rot in the rainy season rains, but the germinating seeds do not have a straight path into the the soil, having to grow around the fruit wall halves, and the distorted seedling has a much lower chance of survival than does the seedling from a seed that was buried by an agouti. In the case of Guazuma ulmifolia fruits, as in this one suspended in space, if the fruit is just left in the soggy litter below the parent, some of the seeds may germinate and produce actual seedlings. However, the seedling is stuck inside the hard fruit structure, and the roots are far above the soil, and such seedlings rarely survive. And even if they do, they are directly in the shade of their parent, probably the worst place in the entire habitat. In a world without horses, such as now occurs in the ACG where the horses have been removed, billions of young guacimo seedlings die directly under their parents and their are essentially no saplings to be found. | ||
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