We would like to respond to the editorial by Ross (2013).

Ross raises ethical concerns regarding the use of privately owned apes in anthropological research, referring specifically to our recently published article in American Journal of Physical Anthropology (Bender and Bender, 2013). In this article, we provide the first report on swimming and diving behavior of two apes (Pongo pygmaeus and Pan troglodytes), and discuss environmental and evolutionary factors influencing water use in hominoids.

We agree with Ross that the welfare of animals should always be central in any research project involving experiments on, or observations of animals, including apes. However, we do not accept Ross' implication that gathering and publishing data on privately owned apes is a legitimation of these holding conditions. As well known, apes are prone to drowning in zoos, since water moats are used to constrain these animals. These accidents occur among others because apes are rarely habituated to deep water in captivity. One of the goals of our work on primates' interaction with water is to understand how water can be used in a safe manner to enrich the environment of captive apes. Our research on privately owned apes is only a small part of the project, which includes data on behavior observed in animals living in different environmental settings (e.g., wild and feral animals, animals kept in sanctuaries, research centers, semifree ranging conditions, and public zoos). Although we agree that private individuals should not own primates, we argue that the ethical discussion regarding holding conditions of captive apes should not be limited to privately owned apes, but include all types of captive settings.

We would also like to clarify that we have ethical clearance from the Animal Ethics Screening Committee of the Witwatersrand University for our study.

  • Renato Bender*

  • School of Anatomical Sciences University of the Witwatersrand Johannesburg 2193 South Africa

  • Institute for Human Evolution University of the Witwatersrand Johannesburg 2193 South Africa

  • Nicole Bender

  • Institute of Social and Preventive Medicine University of Bern Bern 3012 Switzerland

  • Institute for Human Evolution University of the Witwatersrand Johannesburg 2193 South Africa


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