It’s often been debated whether or not nonhuman animals have “theory of mind” (TOM) –– the ability to imagine what others may know or feel. Recent data suggests that chimps may in fact have this ability, crucial to the development of language.
Researchers in the Budongo Forest of Uganda filmed chimpanzees confronted with a fake snake. The chimps reacted with a “hoos” sound and physically retreated.
More significantly, though, the apes repeated the “hoo” calls to other chimps, apparently warning them of the threat. While simple communication does not in and of itself constitute theory of mind, the chimps seemed to adjust their calling depending on which other chimps had or hadn’t known about the danger, implying some awareness (or attempt to be aware) of the level of knowledge of others, a strong indicator of TOM.
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