To celebrate Earth Day, here’s a video featuring the largest mammals on the face of the Earth. At the Elephant Nature Park in Northern Thailand, this man begins to call out for an elephant named “Kham-Lha.” The response he gets sounds like the cry of a dinosaur from Jurassic Park. Only the trumpeting that follows lets you know that these are elephants and that Thailand is not hiding a dinosaur park in their hills.

It’s amazing to see not just Kham-Lha but her entire family come over to say hello to this man and the eager and excited tourists he has gathered. Clearly the elephants love and trust this man and see him as part of their big family. In any case, it’s clear now where they got some of the dinosaur noises from. Elephants are impressive!