Visitors   Views   Downloads
NOT PEER-REVIEWED
"PeerJ Preprints" is a venue for early communication or feedback before peer review. Data may be preliminary.

Additional Information

Competing Interests

The authors declare that they have no competing interests.

Author Contributions

Marlen Fröhlich conceived and designed the experiments, performed the experiments, analyzed the data, wrote the paper, prepared figures and/or tables, reviewed drafts of the paper.

Paul H Kuchenbuch conceived and designed the experiments, performed the experiments, reviewed drafts of the paper.

Gudrun Müller analyzed the data.

Barbara Fruth reviewed drafts of the paper.

Takeshi Furuichi reviewed drafts of the paper.

Roman M Wittig reviewed drafts of the paper.

Simone Pika conceived and designed the experiments, wrote the paper, reviewed drafts of the paper.

Animal Ethics

The following information was supplied relating to ethical approvals (i.e., approving body and any reference numbers):

Our study was of a purely non-invasive nature with audio- and video recordings being taken from a minimum distance of seven meters, thereby aiming to not influence the natural behavior of the individuals, groups and communities. The research adhered to the legal requirements of the countries in which it was conducted and followed the recommendations of the ‘Animals (Scientific Procedures) Act 1986’ as published by the government of the United Kingdom and the principles of ‘‘Ethical Treatment of Non-Human Primates’’, as stated by the American Society of Primatologists.

Field Study Permissions

The following information was supplied relating to field study approvals (i.e., approving body and any reference numbers):

Centre de Recherche en Écologie et Foresterie (CREF; DRC),

nstitut Congolaise pour la Conservation de la Nature (ICCN; DRC),

Uganda Wildlife Authority,

Uganda Council for Science and Technology,

Ministe`re de l’Enseignement Supe´rieure et de la Recherche Scientifique (Côte d'Ivoire)

Office Ivoirien des Parcs et Reserves (Côte d'Ivoire)

Data Deposition

The following information was supplied regarding data availability:

The research in this article did not generate any raw data.

Funding

This study was supported by a Dissertation Fieldwork Grant of the Wenner-Gren Foundation awarded to MF (No. 8784) and a Sofja-Kovalevskaja Award of the Alexander von Humboldt Foundation to SP (No. DEU/1069105). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.


Add your feedback

Before adding feedback, consider if it can be asked as a question instead, and if so then use the Question tab. Pointing out typos is fine, but authors are encouraged to accept only substantially helpful feedback.

Some Markdown syntax is allowed: _italic_ **bold** ^superscript^ ~subscript~ %%blockquote%% [link text](link URL)
 
By posting this you agree to PeerJ's commenting policies