home

Ecology

INTRODUCTION: Ecology is the study of the complex relationships among living things and their physical environment (air, water, soil). Ecology has opened our eyes to the way our own survival, health and prosperity depend on Nature. Key concepts include "the web of life," "balance of nature" and "biodiversity." (Scroll down for links to library documents on this topic.)

THREE FACES OF ONE CONCEPT: These ideas are closely related. The web of life is the complex web of interdependence among plants and animals. It is complex because there are so many animal and plant species, i.e., because of biodiversity. Biodiversity gives the web more strands, making it robust and resilient. The balance of life is just a way of describing what the web does, with each part of it (each species) playing some role in keeping other parts of it alive. When anything disturbs part of the web, the other parts make adjustments to restore the balance. But if the disturbance is big enough, the new balance may not be the same as the old one. Some species may become extinct and new ones arise. Often the species that become extinct include the ones that were formerly dominant. This should give pause to the current dominant species, Homo sapiens, who too often tampers with the web.

EXAMPLES: (1) Plants use sunlight and carbon dioxide exhaled by animals to make food and oxygen that animals need. (2) Predator animals depend on prey animals for food, while prey species need predators to eliminate the weak and aged and control populations so that they don't eat all the plants and starve. (3) Insects, birds and some bats get food from plants, but in the process spread pollen or seeds, thus keeping the plant species alive. There are millions of such examples, complexly interwoven.

WHY THIS MATTERS TO US: Humans depend on the web and balance of nature, too. They are our safety net. We need oxygen and our crops need pollinating. We derive medicines and industrial raw materials from plants and animals. The more biodiversity there is, the more potential there is for new biological sources of wealth. Finally, as spiritual creatures, we value the way biodiversity makes our world more interesting and beautiful. Nature wouldn't care if life consisted only of weeds, roaches and pigeons. But we would.

THE DANGER. Unfortunately, the web of life, the balance of nature and biodiversity are all highly endangered by thoughtless human destruction of animals, plants and their habitats. The biggest threat is habitat destruction caused by humanity’s insatiable demand for land and resources (oil, timber, water). Another factor is the poisoning of the air and water by human-made chemicals and waste. Finally, some species are threatened by overexploitation (commercial fishing) and even by persecution (slaughter of predators). We shall find to our regret that the resources we are destroying are far more valuable than the ones we are harvesting or imagine we are protecting.