Evolution Connection Plant Adaptations in Resource-Deficient Environments A plant's roots, stems, and leaves are designed so that it can access the necessary amounts of
oxygen, water, sunlight, and soil nutrients. Plant species have developed some amazing adaptations
to survive in less-than-ideal environments where one or more of these resources are scarce.
Due to dense plant growth that prevents much of the sunlight from reaching the forest floor,
light is frequently scarce in tropical rainforests. To maximize the capture of sunlight, many tropical
plant species have exceptionally broad leaves. Other species are known as epiphytes, which are plants
that develop on other plants to provide structural support. These plants can flourish in the more
abundant sunlight found higher up in the canopy on the branches of other trees. Rain and minerals
accumulated in the branches and leaves of the supporting plant are the only food sources for
epiphytes. Tropical epiphytes include ferns, orchids, and bromeliads, which are members of the
pineapple family (Figure 112). Numerous epiphytes have specialized tissues that allow for effective
water absorption and storage.
Figure 112. Spanish moss (Tillandsia usneoides), one of the most well-known bromeliads,
can be seen here growing in an oak tree
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Some plants have unique adaptations that enable them to live in environments with
insufficient nutrients. Venus flytraps and pitcher plants, two examples of carnivorous plants (Figure
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(credit: KristinePaulus)
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113), thrive in nitrogen-deficient bogs. These plants have altered leaves that are designed to catch
insects. These plants may have evolved to use the insect-eating leaves as an additional source of
nitrogen.