Many animals emit calls in the presence of food, but researchers do not always know the function of these calls. Evidence suggests that adult golden lion tamarins (Leontopithecus rosalia) use food-offering calls to teach juveniles which substrate (i.e., microhabitat) to forage on, or in, for food. However, we do not yet know whether juveniles learn from this aspect of the adults’ behavior. Here we examine whether juveniles learn to associate food-offering calls with a foraging substrate, as a step toward assessing whether these calls qualify as teaching behavior. We compared the performance of four wild juvenile golden lion tamarins that were introduced to a novel substrate while exposed to playbacks of food-offering calls (experimental condition) to the performance of three juveniles that were exposed to the novel substrate without the presence of food-offering playbacks (control condition). We varied the location of the novel substrate between trials. We found that food-offering calls had an immediate effect on juveniles’ interactions with the novel substrate, whether they inserted their hands into the substrate and their eating behavior, and a long-term effect on eating behavior at the substrate. The findings imply that juvenile golden lion tamarins can learn through food-offering calls about the availability of food at a substrate, which is consistent with (but does not prove) teaching in golden lion tamarins through stimulus enhancement. Our findings support the hypothesis that teaching might be more likely to evolve in cooperatively breeding species with complex ecological niches.

中文翻译：

---

野生金狮狨猴（Leontopithecus rosalia）的食物供给召唤：教学行为的证据？

许多动物在有食物的情况下会发出叫声，但研究人员并不总是知道这些叫声的功能。有证据表明，成年金狮狨猴（Leontopithecus rosalia）利用食物提供的叫声来教导幼体在哪些基质（即微生境）上或其中寻找食物。然而，我们还不知道青少年是否会从成年人的这方面行为中学习。在这里，我们检查青少年是否学会将提供食物的叫声与觅食基质联系起来，作为评估这些叫声是否符合教学行为的一步。我们将四只野生幼年金狮狨猴的表现与三只幼年金狮狨猴的表现进行了比较，这些幼年金狮狨猴在接触新基质的同时，会播放提供食物的叫声（实验条件），而三只幼年金狮狨猴在没有食物的情况下，会接触新基质。提供播放（控制条件）。我们在试验之间改变了新基质的位置。我们发现，提供食物的叫声对青少年与新基质的相互作用、它们是否将手插入基质及其进食行为产生直接影响，并对基质上的进食行为产生长期影响。研究结果表明，幼年金狮狨猴可以通过食物提供的呼叫来了解基质中食物的可用性，这与（但不能证明）金狮狨猴通过刺激增强进行的教学是一致的。我们的研究结果支持这样的假设：教学更有可能在具有复杂生态位的合作繁殖物种中进化。