Many people seem to think that if animals like birds do not talk English, they do not speak. We might not understand what birds, or other animals are communicating, but that does not mean that they do not speak.
Perhaps the phrase can be translated as, ''Look here, there is danger''.
Most scientists and most people think that communication is human unique. However, this is more human superiority. It's like those who think animals do not have much awareness, consciousness, or even think about the future.
This study is amazing, it provides evidence that we humans are not the only smart ones. We can only find out more about animals and empathize more with them (treat them well) when we stop thinking humans are unique and the only ones rich in life of emotions and intelligence.