Editing Helpers at the nest (section)

== Evolution ==
Three explanations for the occurrence of helpers at the nest have been put forward; they are not mutually exclusive, and in any particular species an investigation of the exact benefits and costs will be needed to see what combination of these factors may have driven the evolution of helping.<ref name=":6" />

*Advantage to the helpers, who may be protected from predation, or gain skills that they will need when they subsequently reproduce, as a result of staying in the parental nest.
*[[Kin selection]]: since subsequent litters or broods from the same parents will be full siblings to the helpers, they are as closely related genetically as their own offspring would be. Helping their parents is therefore as productive for the juveniles as reproducing themselves would be, and if their parents are better able to reproduce, the balance of advantage may be greater.
*Delayed advantage to the helpers, in particular because they stand to inherit their parents' [[territory (animal)|territory]]; this explanation is particularly compelling if suitable territories are in short supply, but requires specific quantitative conditions to be met, favouring a stable queue of potential heirs.<ref>{{cite journal|author1=Wiley, R. H. |author2=Rabenold, K. N. |year=1984 |title=The evolution of cooperative breeding by delayed reciprocity and queuing for favorable social positions |url=http://bilbo.bio.purdue.edu/~www_eco/faculty/rabenold/pdfs/EvoCooperativeBreeding%20by%20delayed%20reciprocity.pdf |journal=Evolution |volume=38 |pages=609–621 |doi=10.2307/2408710 |issue=3 |url-status=dead |archiveurl=https://web.archive.org/web/20100617053619/http://bilbo.bio.purdue.edu/~www_eco/faculty/rabenold/pdfs/EvoCooperativeBreeding%20by%20delayed%20reciprocity.pdf |archivedate=2010-06-17 |jstor=2408710 |pmid=28555990 }}</ref>