It has long been debated whether and which species can achieve self-regulation on population level.
Some of the biological and social mechanisms that ensure against overpopulation and overexploitation of resources have been described with respect to large carnivores (apex predators) (i.e., Wallach, A.D. et al., 2015).
Recently I have been reading about the importance of kin recognition in species (i.e., Mateo, J.M., 2003) that either promotes nepotism or inbreeding avoidance.
Kin recognition is sometimes strongly linked with philopatry and the tendency to settle nearby natal range (i.e., Støen, O.-G. et al., 2005).
In many species only one sex is philopatric to natal range (e.g., females in common noctules or males in Ethiopian wolves) while the other sex disperses.
The dispersal of at least one sex can be essential for gene flow within the population and among populations.
However, often one sex (or both sexes) may remain close to natal range or in the natal range (in species, e.g., badgers or wolves where not all subadults and adults necessarily disperse but some can remain in the natal group).
If there is a tendency for a species or for one sex in the species not to disperse or to disperse only as close as possible (energy expenditure savings, familiarity with habitat and its resources, reduced hostility rates during possible conflicts when living close to related individuals etc.), a situation may arise where any specific group is surrounded by individuals that are close kin or more distant kin.
In such species, it can be difficult to attain breeding status because the innate inbreeding avoidance mechanisms disallow to breed within the group or even with the neighbours (if the neighbouring groups are constituted of individuals who dispersed adjacent to natal range).
While it is not beneficial from the individual’s perspective (fitness, reproductive success), it might be beneficial from the perspective of population self-regulation as well as, potentially, to maintain population fitness by eliminating breeders that are incapable of surmounting the obstacles posed to breeding by the buffering effect of the kin distribution (only those individuals who can figure out how to travel far enough, how to differentiate kin from non-kin and how to survive during dispersal and who are healthy enough to achieve the feat of reaching non-related mates, get to breed).
This mechanism, of course, has limitations.
Firstly, the population needs to be saturated enough and stable enough.
In low density populations or in populations with a high turnover, the immigration/emigration flows might be too dynamic to allow for territorial structuring of buffering kin settlements.
Secondly, in some cases, where dispersal is limited, inbreeding might occur and the inbreeding avoidance might be less pronounced.
This mechanism may be even more effective in large, monogamous, long-lived, territorial (or solitary) species.
Notes by Ieva 