A central tenet of the theory is that organisms modify their environments through a process called niche reconstruction or ecosystem engineering, the prime example being the activities of humans. Such modification can have profound effects on the distribution and abundance of organisms, the influence exerted by key species, the control of energy and material flows, residence and return times, and ecosystem resilience to changing circumstances. The modifications are not restricted to ecology, but also to the possibility that they can affect both their own and each other’s evolution through modifying sources of natural selection. The theory also attempts to describe and explain a number different phenomena: the ways in which species interact (including predator-prey and resource competition), why some species are infrequent and others abundant), what determines the geographical distribution of a given species and what determines the structure and stability of many species living in the same region and interacting with each other.
See Biological evolution, Ecology, Ecosystem, Habitat (ecology), Natural selection, Niche (ecology), Species, Theory of natural selection