In a study of the cooperatively breeding cichlid fish *Neolamprologus pulcher*, evolutionary biologist Dr. Marcus Vance investigated the "pay-to-stay" hypothesis. This hypothesis suggests that subordinate helpers assist in territory defense and offspring care not solely due to kin selection, but as a form of "rent" to prevent dominant breeders from expelling them from the safety of the territory. Vance argued that if helping is indeed a transaction to secure territory residency, dominant breeders should respond to a helper's temporary inactivity with increased social policing (aggression) only when resources are scarce, as the cost of hosting a non-productive helper is higher under these conditions.
Which finding, if true, would most directly support Vance's argument?
- In experimental trials where subordinate helpers were prevented from assisting in territory defense, dominant breeders directed significantly more aggressive behaviors toward the inactive subordinates in resource-scarce environments than they did in resource-abundant environments.Cevap
- BSubordinate helpers in resource-scarce environments performed significantly more defensive behaviors on average than did subordinate helpers in resource-abundant environments.
- CDominant breeders in resource-abundant environments exhibited high levels of aggression toward all subordinate helpers, regardless of whether those helpers actively participated in nest defense.
- DUnrelated subordinate helpers were expelled from territories at similar rates as closely related subordinate helpers when both groups failed to assist in offspring care.