Interestingly, almost every time researchers have proposed that humans can do something that other animals cannot because humans have language, studies have shown that some animals can do some of those things, at least some of the time.
Animal researchers were the first to challenge the definition of language as a discretely human attribute. As comparative psychologist Heidi Lyn has pointed out, the only way we can truly determine what is unique to human language is to explore the capacities of other animals. Interestingly, almost every time researchers have proposed that humans can do something that other animals cannot because humans have language, studies have shown that some animals can do some of those things, at least some of the time.