“…Some of the first authors for comments are also, or primarily, interested in cooperation theory (Connor, 2007;Hamilton, 2007;Kokko, 2007;Noë, 2007;Roberts and Sherratt, 2007;Sachs and Rubenstein, 2007;Skubic, 2007), but most commentaries were provided by empiricists in the field of cooperation, most of them working on cooperatively breeding species. These authors covered much of the broad spectrum of cooperatively breeding animal taxa ranging from social insects (Field and Cant, 2007;Korb and Heinze, 2007), fishes (Buston and Balshine, 2007;Hamilton, 2007;Skubic, 2007;Taborsky, 2007), birds (Berg and Williams, 2007;Cockburn, 2007;Covas et al, 2007;Doerr et al, 2007;Ekman, 2007;Hatchwell, 2007;Komdeur, 2007;Wright, 2007) to mammals (Connor, 2007;Gilchrist, 2007) including primates (Noë, 2007;Snowdon and Cronin, 2007) and humans (Kramer, 2007). We hope this joint effort will also contribute to close the prevailing gap between research on invertebrate and vertebrate cooperative breeding and foster communication between the fields.…”