Killer whales whistle, finches twitter, and hyraxes wail. But all of these sounds have long been considered fundamentally different from human language—indeed, so different that scientists haven’t been able to find any intermediate evolutionary steps between animal calls and language. Now, a new study reveals that the calls of animals contain more languagelike characteristics than previously believed. Scientists reached this conclusion after analyzing the vocal sequences of seven species of birds and mammals, from Carolina chickadees to bats and orangutans. They found that animal vocalizations must be generated by complex statistical processes, making them more similar to human language. In the past, researchers assumed that a “Markovian” model best explained the vocal sequences in animal calls. According to this model, animal calls are fairly random and lack the complexity of human language. However, no one had actually tested the Markovian model on animal vocalizations until now. After applying it to the various species’ calls, the researchers report this week in the Proceedings of the Royal Society B that they found no evidence that animals’ vocalizations are restricted as the model would suggest. And that means the gap between human language and animal calls is not so wide after all.