Elaine Knox, age 14, Ottawa Ontario
What is symbiosis?
This word has a meaning as pleasant as its sound. It means a successful partnership of give and take. Symbiosis is coined from two Greek words for live and together. Sometimes two plants live happily together in symbiosis, sometimes life is shared by two animals, and sometimes the partnership is between a plant and an animal.
The lichen is an example of symbiosis between two plants. Each flat rosette of lichen is a fungus plant plus a host of tiny algae plants. The fungus provides housing and moisture. The algae use their chlorophyll to make enough food for themselves and the fungus.
Certain sponges enjoy life in symbiosis. The sponge, of course, is a animal. Green,. fresh water sponges get their color from green algae. This is a partnership between the plant and animal kingdom.
Tiny bacteria are rated as members of the animal kingdom. They ate great ones for living in partnership with either plants or animals. Certain bacteria can take nitrogen gas from the air and fix it in solid compounds. This is a mighty important job. For nitrogen is one of the vital soil chemicals. Without it, crops fail and the earth becomes barren.
Luckily for us, certain of these bacteria team up with plants of the legume family. They live happily in the roots of beans, peas and clover plants. The plants provide them with little bulbs along the root fibers. The bacteria are sheltered and moist in the cells of their little homes. There they use their secret recipe for making nitrogen compounds. The plant and the bacteria thrive on this food. There is even enough nitrogen left over to enrich the soil for next years crops, That is why the farmer plants a tired field with a legume crop. Instead of being robbed of plant food the soil is enriched by the symbiosis between plants and bacteria.
Many animals are green in color because they live in symbiosis with certain green algae. There is a sea worm of the 0ld World who lives a dramatic life cycle in symbiosis with green algae plants. The baby worm feeds for itself, Sooner or later it devours some of the algae. They multiply and provide food for themselves and the worm. Then the worm stops bothering to eat for itself. Lastly it digests its little partners and perishes.
The insects are great ones for forming these give and take partnerships. Certain ants keep aphids like dairy farmers. They tend their little cattle, place them near food and protect their eggs. In return, the aphids give off sticky honey dew which the ants love to eat.
The lives of countless plants and animals are improved by symbiosis. There is no telling how many such partnerships exist in the world. The bees take nectar and in return they spread the pollen from the flowers. Maybe a tree grows because a squirrel buried a nut and forgot where he hid it. These happy events are also examples of symbiosis.