Thanks for your suggestions. I am definitely not happy with all aspects of the video - and I agree with you about the ending. For the second video we will likely do a few things differently.

1. A courtship ritual or grooming pattern is classified to be cultural based on a few factors. A) it has to be something that is context specific (i.e., chimp x and chimp y are good friends and they always clasp hands in a certain way that they would never do with chimp z). B) it is a behaviour that is not universal and/or is diffused in a way one would expect if it was socially learned and passed down from generation to generation. C) It is something that is not ecologically determined (i.e., the behaviour can be explained away based on whether or not there is a certain ecological feature that is absent at another site).

2. In terms of overall cultural variants chimpanzees don't really have any close competition at the moment. I recently wrote about culture in other great ape populations if you want to learn more about that. Few studies have been done and we will continue to learn more about how culture varies between great ape species. And to be honest it is hard to compare culture in great apes to culture in cetaceans and birds for example. In my mind, it appears as though great apes, cetaceans, and birds excel at different types of cultural behaviours, and although chimpanzees possess the highest number of cultural variants, New Calendonian Crows have produced the best evidence for cumulative culture (which I will be writing about in the near future).