their social networks. Dunbar commented the choice of data for this study, however, now stating that his number should not be calculated from data on primates or anthropoids, as in his original study, but on apes. This would mean that his cognitive limit would be based on 16 pair-living gibbon species, three solitary orangutans, and only four group living great apes (chimpanzees, bonobos and two gorilla species), which would not be sufficient for statistical analyses. Philip Lieberman argues that since band societies of approximately 30–50 people are bounded by nutritional limitations to what group sizes can be fed without at least rudimentary agriculture, big human brains consuming more nutrients than ape brains, group sizes of approximately 150 cannot have been selected for in paleolithic humans. Brains much smaller than human or even mammalian brains are also known to be able to support social relationships, including social insects with hierarchies where each individual "knows" its place (such as the paper wasp with its societies of approximately 80 individuals) and computer-simulated virtual autonomous agents with simple reaction programming emulating what is referred to in primatology as "ape politics". Comparisons of primate species show that what appears to be a link between group size and brain size, and also what species do not fit such a correlation, is explainable by diet. Many primates that eat specialized diets that rely on scarce food have evolved small brains to conserve nutrients and are limited to living in small groups or even alone, and they lower average brain size for solitary or small group primates. Small-brained species of primate that are living in large groups are successfully predicted by diet theory to be the species that eat food that is abundant but not very nutritious. Along with the existence of complex deception in small-brained primates in large groups with the opportunity (both abundant food eaters in their natural environments and originally solitary species that adopted social lifestyles under artificial food abundances), this is cited as evidence against the model of social groups selecting for large brains and/or intelligence. Popularisation Malcolm Gladwell discusses the Dunbar number in his 2000 book The Tipping Point. Gladwell describes the company W. L. Gore and Associates, now known for the Gore-Tex brand. By trial and error, the leadership in the company discovered that if more than 150 employees were working together in one building, different social problems could occur. The company