Degree Type


Date of Award


Degree Name

Master of Arts



First Advisor

Jill Pruetz

Second Advisor

Sue Fairbanks

Third Advisor

Chrisy Moutsatsos


I studied male western lowland gorillas (Gorilla gorilla gorilla) in a captive setting in order to determine if post-conflict reconciliation exists in male-male dyads of this species. I also examined conflict itself in order to determine the consequences of housing these males together in all-male groups in captivity. This was accomplished by examining the behaviors of nine male gorillas at the Henry-Doorly Zoo in Omaha, Nebraska. Data that I recorded included post-conflict observations, social interactions, and activity budgets. I analyzed the data in order to determine levels of reconciliation, welfare of the population, and comparisons with wild conspecifics. I hypothesized that males in this species would differ from mountain gorillas (Gorilla gorilla beringei) based on ecological and species' variations: that they would exhibit reconciliation. I rejected this hypothesis. However, lack of observed conflict between those individuals comprising 'valuable' relationships suggests that further study be done in order to examine whether postconflict reconciliation exists in this type of social setting. Results on conflict itself show that the age of the youngest in a dyad determines the characteristics of that relationship. In particular, affiliation levels all but diminish once the age of the youngest in a dyad reaches twelve years, which is also the approximate silverback transition period for male gorillas. In addition, conflict begins to appear, where it was almost non-existent before, at this critical age. Because male gorillas in the wild generally separate themselves from other adult males around this age (to become solitary or form their own one-male group), it is not surprising, then, that conflict should ensue in captivity where natural emigrations cannot occur. Therefore, I suggest that captive all-male gorilla groups may not form a long-term solution to the 'surplus' of male gorillas in captivity.



Digital Repository @ Iowa State University,

Copyright Owner

Jackie Elizabeth Davenport



Proquest ID


OCLC Number




File Format


File Size

97 pages