New News Biology #65

Interdependence - Community and Competition

Ecology - all organisms have relationships (e.g. mice and other mice, predators of the mice, food that the mice eat, and all the other animals that live nearby).

Some special terms:

Habitat - where an organism lives

Population - all the organisms of a particular species that live in that habitat

Community - all the populations of a different species that live together in a habitat.

Biotic factors - living factors of the environment*

Abiotic factors - non living factors*

New News Biology #64

If we put all these factors together, we get an ecosystem (an interaction of a community of living organisms with the non living parts of their environment).

One of the most important processes in an ecosystem is competition. Any organism needs a variety of different resources in order to survive and produce offspring. For animals, some of those resources include space (territory), food and water, and mates (to reproduce). For plants, they need light (for photosynthesis, space, and soil (where they can extract water and mineral ions). The problem is that these resources are limited, so organisms (both from same species and different species) have to compete.

Another term is interdependence (all species depend on other species in some way). When we look at a food web, interdependence becomes quite clear. The consumers rely on the producers, while the consumers’ predators rely on the consumers as food to survive, and so on. A sudden increase or drop in any part of the food web is very likely to affect even the most far edges of the food web (and the ecosystem in turn).