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Epiphytes are shrubs and herbs that attach their roots on trunks or branches of other trees. The main purpose of this is so that these shrubs are able to capture as much bright light as possible. Down on the forest floor, much of the light has been blocked of the canopy layer. Epiphytes generally do not extract nutrients from their host plants or endanger them. However, there are exceptions. Those epiphytes from the family Mistletoe and other parasitic shrubs that penetrate the wood of the host trees. From this, they extract water and mineral nutrients. Most epiphytes have thick leaves. Orchids for example, have fleshy leaves and thick stems, together with ferns. Some also have tubers. This is to help them adapt to the surrounding where water is deficient and temperature is high. Some epiphytic plants have also evolved which allows them to absorb and store carbon dioxide during the night, where the temperature is cooler and use them later during the day for photosynthesis. This helps in lessening water loss. Epiphytes reproduce with the help of wind dispersal, and many do so by producing spores. Examples of spore bearing plants include the ferns and the lipstick plant. Some species of epiphytes resort to other methods of dispersal other than through wind. Such is the mistletoes, which produces berries, which is eaten and distributed by birds and even ants. Epiphytes root themselves on areas where there is little humus. To resolve these problems, many species such as the Bird Nest Fern and Stag’s Horn Fern have stiff big leaves to trap falling leaves. Bacteria and fungi then help to break down these dead leaves providing the epiphytes with protective mulch, that works as well as humus. Others even resort to ants that help to bring up humus from the ground. The ant plants even have special structure for the ants to live and multiply. Examples of epiphytes includes ferns, mosses, orchids, bromeliads, and vines. Two flowers of the orchid family which can be found are the brownea and the heliconia. The flower of the brownea is bright orange and hangs off trees. It is filled with pollen grains. Heliconia is basically similar to the brownea except that it is bright red and green. Among the most successful of epiphytes are the orchids. Orchid is a diverse group of epiphytes, with 18,000 of them already been given scientific names and 10,000 are still yet to be studied. Every wet tropical rainforest has their share of orchid epiphytes. The rainforest of South America and Southeast Asia seems to have the most of the share. One reason why orchids are abundant is due their effective dispersal method. Their seeds are the smallest among flowering plants and they are produced by the hundreds and thousands and dispersed miles and miles away by wind. Even after they have germinate, orchids develop highly advanced techniques for survival. One such feature is the presence of an absorbent layer that surrounds the roots. Threads of fungal also grow on the roots of orchids that help to digest organic debris releasing nutrients absorbed by the orchid. Some species don’t seem to be satisfied by wind dispersal for pollination and even get the help of insects to do the job. Species of orchids found in Madagascar have nectars situated deep in the flowers and releases perfume that attract several species of sphinx moth. Pollen gets stuck on the moths while it snuggles deep into the flower to reach the nectar. One interesting pollination process is seen in corsage orchids found in Central and South America. These colourful flowers secrete spicy fragrances instead of nectar. Male bees in the tribe Euglossini carry "perfume flask" and collect these pungent compounds and along the way help in pollinating the flowers. MORE INFO ON THE WEB
Bromeliads are abundant in South American rainforest, and not anywhere else. Bromeliads are empiphytes, and it has strap shaped leaves clustered in a rosette surrounding a central cup. To survive with the water problems in an arboreal habitat, bromeliads have evolved to enable them to collect water in the spaces in between the leaves. And in these pool of water, there are debris such as dead insects that when decomposed, released nutrients which is essential to the growth of the bromeliad. Some species of bromeliads have even gone a step further by having enzymes that kill and digest insects in the watertank. The bromeliad itself is a mini habitat of its own. Within this water tanks, there may contains insect larvae such as those of mosquitoes, and tadpoles of poison arrow frogs. Bromeliads are also a source of drinking water for some monkeys and homes to creatures such snakes, spiders and even scorpions. MORE INFO ON THE WEB
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