Here is link to study showing another cortical area distinct to humans: http://earthsky.org/human-world/brain-area-seems-to-be-uniquely-human#.UvTNha8V0Cw.email
This is a small area in the ventrolateral frontal cortex likely involved in planning and flexible implementation. It is well connected with language areas in the temporal cortex.
Homologies are structures which are similar across species because of common if distant ancestry. This area is not homologous with other animals; it is ours. I recently read that dolphins, whose brain size in relation to body size matches ours, also have their own structure, the rather large paralimbic cortex. Extrapolating from human studies it would appear to be involved in social and emotional communication. Given its proximity to the hippocampus it may also help with spatial mapping. Dolphin brains differ from primate brains in another way. Their cortex is not layered like ours is. Instead the cell types are intermingled and without the layered, columnar organization. I saw a study late last year brilliantly done by Scottish researchers demonstrating that dolphins call each other by names and that Scottish dolphins seem to have a different sort of dialect than ones off the Azores. Who knew? But brilliant.