Do anvil-using banded mongooses understand means–end relationships? A field experiment

Abstract

Tool use and the associated need to choose appropriate objects for a particular task are thought to have selected for specialized cognitive abilities such as means–end comprehension. Several studies on large-brained tool-using primates and birds have demonstrated understanding of causal relationships to some extent. However, a comprehensive appraisal of this hypothesis requires testing for means–end comprehension also in non-tool-users as well as in small-brained tool users. Moreover, the results of captive studies do not answer the question whether such cognitive abilities are relevant to an animal in its natural environment. Here I presented wild banded mongooses Mungos mungo, small-brained carnivores that regularly use anvils to open food items with a hard shell, with a transfer test involving novel anvil objects. I found no evidence for means–end comprehension or a heuristic strategy used for anvil choice in this species. Instead, recognition of suitable anvils appears to be learned by trial and error separately for different categories of anvils. These data suggest that, at least for the anvil-choice task investigated here, the need to choose suitable objects has not selected for specialized cognitive abilities in banded mongooses, a finding that may extend to a large range of proto-tool users. Furthermore, this study adds to growing evidence that animals subjected to the selection pressures and trade-offs of their natural environment may get by with cognitively more simple strategies than sometimes suggested by captive studies or plausibility arguments.