“…Our results corroborate these shortterm positive effects of group size, suggesting group size also has long-term effects: larger groups were less likely to go extinct and large groups also tended to be large a year later. Positive effects of group size on survival and reproductive success are widespread in cooperatively breeding birds (e.g., Conner et al, 2004;Khan & Walters, 2004;Russell et al, 2004, see also some species listed in Stacey & Koenig, 1990), rodents (e.g., Allainé et al, 2000Waterman, 2002), carnivores (Rood, 1990;Clutton-Brock et al, 2001b;Courchamp et al, 2002;Russell et al, 2002; see review Russell, 2004), and primates (e.g., Heymann & Soini, 1999;van Noordwijk & van Schaik, 1999), but not always (e.g., Rogovin et al, 2004;Seddon et al, 2004). It should be remarked, however, that the majority of these studies are correlational, i.e.…”