It is predicted that as population size increases toward carrying capacity, density-dependent mortality increases, therefore slowing the growth of the population. One exception that is observed in nature is the Allee effect. Because some species benefit from a positive relationship between components of individual fitness and either numbers or density of conspecifics (as discussed in the section entitled 'Individual behavior'), density-dependent mortality no longer linearly increases to carrying capacity. Rather, it has the potential to be curvilinear where it is observed to be strong at both small and large populations but weaker at intermediate levels (Figure 4). For example, cooperative breeders, such as African wild dogs (Lycaon pictus), may have a critical group size below which the group would be more likely to go extinct due to increased mortality.
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