Keystone Species
By analyzing network structures, one can determine keystone species that are of particular importance. A different class of keystone species is what are termed ‘ecosystem engineers’. Certain organisms alter the environment so drastically that it affects many interactions that take place within a habitat. This term is used for organisms that “directly or indirectly modulate availability of resources (other than themselves) to other species, by causing physical state changes in biotic or abiotic materials”. Beavers are an example of such engineers. Other examples include earthworms, trees, coral reefs, and planktonic organisms. Such 'network engineers' can be seen as “interaction modifiers”, meaning that a change in their population density affects the interactions between two or more other species.
Read more about this topic: Non-trophic Networks
Famous quotes containing the word species:
“Genius detects through the fly, through the caterpillar, through the grub, through the egg, the constant individual; through countless individuals the fixed species; through many species the genus; through all genera the steadfast type; through all the kingdoms of organized life the eternal unity. Nature is a mutable cloud which is always and never the same.”
—Ralph Waldo Emerson (1803–1882)