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Some animals give specific calls when they discover food or detect a particular type of predator. Companions respond with food-searching behaviour or by adopting appropriate escape responses. These signals thus seem to denote objects in the environment, but this specific mechanism has only been demonstrated for monkey alarm calls. We manipulated whether fowl (Gallus gallus) had recently found a small quantity of preferred food and then tested for a specific interaction between this event and their subsequent response to playback of food calls. In one treatment, food calls thus potentially provided information about the immediate environment, while in the other the putative message was redundant with individual experience. Food calls evoked substrate searching, but only if the hens had not recently discovered food. An identical manipulation had no effect on responses to an acoustically matched control call. These results show that chicken food calls are representational signals: they stimulate retrieval of information about a class of external events. This is the first such demonstration for any non-primate species. Representational signalling is hence more taxonomically widespread than has previously been thought, suggesting that it may be the product of common social factors, rather than an attribute of a particular phylogenetic lineage.

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Despite the ubiquitous presence and vital role of invertebrates in all known ecological systems, insects and arachnids are largely viewed as repugnant by people. Consequently, until nature intervenes in the form of infestations, swarms or plagues, we largely prefer to ignore them, lest our attention invite unwelcome interaction. In contrast, the people of ancient Egypt did not distance themselves from invertebrates but instead celebrated their myriad forms. Egyptian appreciation of insects and arachnids is reflected in a range of art, artefacts, and texts dating from the predynastic era until the Greco-Roman period, revealing many positive cultural roles, from practical to conceptual. By assigning them a useful function, they were rendered visible and relevant to Egyptian society. The Egyptians’ example suggests that as necessity forces us to acknowledge the value of invertebrates—from their function as pollinators to becoming future food sources—our respect for them may also grow.