A short selection from Essay Fourteen in Darwin, Dogen, and the Extremophile Choice
According to modern ecological theory, high diversity at any trophic level of a community is possible only under the influence of cropping. —Steven M. Stanley, 1973 
The wolf makes the deer strong. —Oji-Cree stone-age wisdom
Though the young of a species are generally more expendable than its more heavily invested adult organisms, most species do not normally prey upon their own. This is just good ecological accounting. Evolution, on the other hand, relies on the broader truth that species are nothing other than inbreeding populations that sometimes grow to more expendable proportions, and in the process might increase their ecological scope. When a species reaches this advanced stage of ecological disparity, a new set of rules begins to apply: if (and indeed, given sexual selection, when) such sub-species diverge beyond the point where they no longer interbreed, these now non-familial products of true population branching, must subsequently relate to each other in a mostly dietary way. Here organisms, though they remain inter-breeding members of a single species, become diners or dinners (or in the case of predator leaving food for scavenger, ‘utensils’) in an even larger club whose inter-feeding members are species themselves.
With our view limited to a lifetime, this non-interbreeding, non-family club takes the mosaic form of a vast inter-validating food-web that casually links many tighter but shorter feeding-chains;  and yet this is only an immediate eco-logic section of that age-consuming phylogenic ‘tree’ we imagine when we view the geologically compressed record of dead organisms and extinct species. Organisms are the acts, and species the concepts, in the larger story of evolution, but the real characters are fully deployed ecological ‘canopies’. These mature ecosystems can ‘shade new growth’ for millions of years, then, ‘suddenly’, in response to some unearthly or in-earthly pruning, they ‘learn’ to reform themselves entirely. At such points of upheaval, new and vigorous branches punctuate our narrative, and Natural history is captured with this image of an unfolding, non-seeding, endlessly speci-fying, dietetically reticulating tree of life.
1. Stanley, Steven M. 1973. “An Ecological Theory for the Sudden Origin of Multicellular Life in the Late Precambrian”. In Proc. Nat. Acad. Sci. USA vol. 70, no. 5, pp. 1486-1489.
2. Wilson, Edward O. 1992. The Diversity of Life. Cambridge, Mass: The Belknap Press of Harvard University Press. pp. 180-181.