Information AboutHerbivore |
| CATEGORIES ABOUT HERBIVORY | |
| herbivoryherbivory | |
| eating behaviors | |
| predation | |
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Herbivory is a form of Predation in which an Organism known as an herbivore, Consume s only Autotroph sCampbell, N. A. (1996) ''Biology'' (4th edition) Benjamin Cummings, New York ISBN 0-8053-1957-3 such as Plant s, Algae and photosynthesizing Bacteria . By that definition, many Fungi , some Bacteria , many Animal s, some Protist s and a small number of Parasitic Plant s can be considered herbivores. Herbivory is generally restricted to animals eating plants, however. Fungi, bacteria and protists that feed on living plants are usually termed Plant Pathogens . Microbes that feed on dead plants are Saprotroph s. Flowering plants that obtain nutrition from other living plants are usually termed Parasitic Plant s. HERBIVORES In Zoology , a herbivore is an Animal that is adapted to eat primarily Plant matter (rather than Meat ). Although such animals are sometimes referred to as being Vegetarian , this term is more properly reserved for Human s who choose not to eat meat as opposed to animals that are unable to make such choices. s feed on leaf tissue between the epidermal layers]] Herbivores can be further classified into various sub-groups, such as Frugivore s, which eat mainly Fruit ; Folivore s, which specialize in eating Leaves ; Nectarivore s, which feed on Nectar ; among herbivorous Insect s and other Arthropod s, the level of feeding specialization can be far more fine-tuned, including seed-eaters (" Granivore s"), pollen-eaters (" Palynivore s"), plant fluid-feeders (" Mucivore s"), and those specialized to feed on wood (" Xylophages ") or roots (" Rhizophages "). In other animals, the degree of specialization is not so advanced, however, and many fruit- and leaf-eating animals also eat other parts of plants, notably Root s and Seed s. The diets of some herbivorous animals vary with the seasons, especially in the Temperate Zone s, where different plant foods are most available at different times of year. There is a misperception that if an animal is herbivorous, it represents less danger to humans than a , Leopard , Cape Buffalo , Elephant and Lion ), three are herbivores. Herbivores form an important link in the food chain as they transform the sun's energy stored in the plants to food that can be consumable by Carnivore s and Omnivore s up the food chain. As such, they are termed the primary consumers in the food chain. PLANT DEFENCES See Also: Plant defence against herbivory Plant defense against herbivory include a range of Adaptation s evolved by plants to improve their survival and reproduction by reducing the impact of animals that eat them. Plants have evolved an enormous array of mechanical and chemical defenses against herbivores. These defenses include mechanical protections on the surface of the plant, production of complex Polymers that reduce plant Digestibility to animals, and the production of Toxins that kill or repel herbivores. Defenses can either be ''constitutive'', always present in the plant, or ''induced'', produced or translocated by the plant following damage or stress. The term host plant resistance is also used by plant breeders to refer to these mechanisms. Plants have also evolved features that enhance the probability of attracting natural enemies to herbivores. Specifically, they emit '' Semiochemical s'', odors that attract natural enemies, and provide food and housing to maintain the natural enemies’ presence. A given plant species often has many types of defensive mechanisms, mechanical or chemical, constitutive or induced, which additively serve to protect the plant, and allow it to escape from herbivores. HERBIVORE ADAPTATIONS TO DEFENCES See Also: Herbivore adaptations to plant defense Herbivores are dependent on plants for food, and have ary change. When an herbivore eats a plant it Select s for plants that can mount a defensive response, whether the response is incorporated Biochemically or physically, or induced as a counterattack. In cases where this relationship demonstrates “specificity” (the evolution of each trait is due to the other), and “reciprocity” (both traits must evolve), the species are thought to have coevolved.Futuyma, D. J. and M. Slatkin. 1983. Introduction. Pages 1−13 in D. J. Futuyma and M. Slatkin, editors. Coevolution. Sinauer Associates Inc., Sunderland, Massachusetts, USA. The escape and radiation mechanisms for coevolution, presents the idea that adaptations in herbivores and their host plants, has been the driving force behind Speciation .Ehrlich, P. R. and P. H. Raven. 1964. Butterflies and plants: a study of coevolution. Evolution 18:586-608.Thompson, J. 1999. What we know and do not know about coevolution: insect herbivores and plants as a test case. Pages 7–30 in H. Olff, V. K. Brown, R. H. Drent, and British Ecological Society Symposium 1997 (Corporate Author), editors. Herbivores: between plants and predators. Blackwell Science, London, UK. SEE ALSO REFERENCES EXTERNAL LINKS |
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