First of all, there are consumers in plants and fungi.
It is natural for animals to eat plants, but there are more than 500 kinds of plants that feed on animals and plants in the world, forming a special group in the ecosystem. Among these plants, some are both producers and consumers, and some are complete consumers.
Insect-eating plants mainly prey on insects and often live in nitrogen-deficient environments, or their roots are underdeveloped or even degraded. Due to the insufficient supply of nutrients made by leaves, they have formed the ability to prey on insects and obtain organic matter in the long-term evolution process. For example, some plants such as Nepenthes and Nepenthes. Some of these plants rely on the closure of leaves, some rely on the viscous liquid secreted by glands, and some rely on the movement of touching hair to catch insects, which can secrete digestive juice to digest insects to make up for the lack of nutrition. Therefore, these plants are both producers and consumers.
Plants that feed on plants do not contain chlorophyll, their leaves are degraded, and only reproductive organs are developed. They get nutrients from host plants, so they are called parasitic plants. Such as the well-known tussah silk parasitic on soybeans, horses and other plants; The flesh is parasitic on the roots of red sand, salt claws, etc. Rodents parasitic on Artemisia of Compositae; Wild shavings parasitic on the roots of sugarcane are out-and-out consumers. Most fungi cannot produce their own nutrients. They decompose other living organisms through hyphae and absorb their nutrients to maintain life, so they belong to decomposers. However, some fungi are insect-eating fungi because they prey on some tiny animals, such as nematodes, rotifers and caterpillars. According to statistics, there are about 50 different kinds of insect-eating fungi in the biological world.
Second, animals are not just consumers.
Most animals are consumers, but some animals are producers and decomposers.
Some contain chloroplasts and live a completely autotrophic life, that is, producers, such as trichomonas. Other animals, such as green eyes, can carry out photosynthesis and lead an autotrophic life under the condition of light; But in the dark, it is permeated with nutrition and leads a heterotrophic life, so it is both a producer and a consumer in the ecosystem. Animals in a rotting state mainly refer to scavengers, and large scavengers such as raccoons and hyenas specialize in eating animal carcasses; Small scavengers, such as aquatic tadpoles, crayfish, crabs, some mollusks (such as clams) and terrestrial earthworms, termites, cockroaches, etc. , can decompose the bodies, excrements and residues of animals and plants. Therefore, according to the traditional classification method, they can be divided into consumers and decomposers.
Third, the status of the virus in the ecosystem.
Generally, in ecology, the position of virus in ecosystem is not discussed, and the role of virus in ecosystem is ignored. Viruses are a unique group in the biological world. They are composed of protein and nucleic acid, and have no cell structure. Therefore, the virus can not be separated from living cells, but its role and position in the ecosystem can not be ignored.
Judging from its nutritional mode, the virus only transforms the host organic matter into its own substance when it lives parasitically, but does not transform the organic matter into inorganic matter and return to nature. Therefore, unlike bacteria and fungi, viruses belong to consumers in the ecosystem.
It can be seen that the position of an organism in the ecosystem should not be determined simply by its taxonomic position in the biological world, but by its nutritional mode and function in the ecosystem. Knowing this, it is not difficult to divide the position of organisms in the ecosystem.