We know that individual trees belonging to certain temperate species can be very old (cf. sequoias and bristlecone pines), but we know much less about the trees of tropical rainforests. These trees cannot be dated by examining annual rings, as many temperate trees can, since rings do not form or are irregular in the absence of regular annual climatic cycles. By means of carbon dating (dating based on the degree of decay of radioactive carbon in the wood), some rainforest trees have been estimated to be more than 1,400 years old (Chambers, et al., 1998). Although plants grow rapidly in the rainforest environment, because of competition, most will die, and only a few will grow into huge “emergents” (trees which are so tall that they emerge from the canopy). Estimates of time required for an emergent tree to grow from a seedling to 100 cm in diameter range from 90 to 600 years (Chambers, et al., 1998). Some species of trees may grow rapidly when emerging through the canopy and then grow slowly to maximum size. Other species may grow slowly and regularly throughout their life span (confounding the conventional idea of rapidly growing tropical species). Other species may have more complex growth patterns, but we do not know much about them.

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