Photographer’s claim is that the photo isn’t in the public domain because the he did all the setup and all the monkey did was take the picture.
Wikimedia’s claim is that for the photographer to claim copyright, they “would have had to make substantial contributions to the final image, and even then, they’d only have copyright for those alterations, not the underlying image”. And because animals aren’t people and don’t have civil rights then the images fall under the public domain.
TODO insert pun about monkey business and copyright.
Update (21 August, 2014 at 3:10pm)
The U.S. Copyright Office says that the photograph is unprotected by intellectual property.
The Office will not register works produced by nature, animals, or plants. Likewise, the Office cannot register a work purportedly created by divine or supernatural beings, although the Office may register a work where the application or the deposit copy state that the work was inspired by a divine spirit
Compendium of US Copyright Office Practices, Third Edition (PDF Copy of the Report).