Noonburg & Byers (2005) used a food‐web model to explain coexistence of prey species when both exploitative and apparent competition occurred simultaneously. How-ever, the change in the mean density of one species. But, the question still remains whether the observed behavior is dependent upon the spatial structure of the model, or whether it could also happen in a non-spatial version. This effect of apparent competition has been recently demonstrated by experiments using a host–parasitoid system (Hassell and Bonsall). Figures 2-8 follow. apparent competition in endangered species conservation, we have three primary objectives: (1) to review the me-chanics of apparent competition dynamics among predator and prey, including revisiting Holt’s (1977) original theore-tical model; (2) to review recent studies showing apparent competition and the sources of human-induced asymmetry See Apparent Competition and Biocontrol for the accompanying text. In competition theory, resources are often, but not always, assumed to have very simple dynamics, and intra- and inter- Their modeling of a single‐resource system, however, assumed that prey species must compete for the same resource in order to exist, whereas Holt's (1977) model assumed the opposite. Imagine a single species of predator or parasite that attacks two species of prey (or host). Joseph H. Connell, Apparent versus “Real” Competition in Plants, Perspectives on Plant Competition, 10.1016/B978-0-12-294452-9.50006-0, (9-26), (1990). caused by a small change in the harvest rate of another. described as apparent competition in this model. Another reason for being cautious in our discussion of competition is the existence of what Holt (1977, 1984) has called 'apparent competition', and what others have called 'competition for enemy-free space' (Jeffries & Lawton, 1984, 1985). The CAM-8 model illustrates the phenomenon of apparent competition in an explicitly spatial model. In order to study the consequences of predator-mediated apparent competition in isolation from other complicating factors, a model community is analyzed in which there is no direct interspecific competition … There are thus marked symmetries between competition and apparent competition, but there are also differences. The model was able to predict the actual relative abundances of D. aurita and M. nudicaudatus in the three empirical studies analyzed. The effect of a shared parasite on the dynamics between two host species has been investigated by mathematical models ( Hudson and Greenman, 1998 ; Greenman and Hudson 1999 , Greenman and Hudson 2000 ). Apparent competition is a situation in which it appears that two species compete for limited resources, because the presence of one reduces the abundance of the other. 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