Dwayne Johnson joined The Ellen Show to discuss his upcoming role in the movie Rampage, where he portrays a primatologist. He shared how he readied himself for the adventure film by visiting researchers at the Dian Fossey Gorilla Fund in Atlanta.

“This was the very first time I had any kind of interaction with a gorilla and a silverback,” Johnson said. “So down in the Atlanta zoo, it’s the biggest population of silverbacks that we have in the United States. So the primatologist who was in charge of feeding Taz, she said, ‘Okay, it may take him a while to get here.’ She goes, ‘I just want to warn you. You’re an alpha, he’s gonna sense that and feel it. He’s gonna become very aggressive. He may start pounding on the cage, he may start grunting—moving back and forth very fast at you.’ She says, ‘It’s just going to be part of the process.’ I’m like, ‘Okay.’”

He continued, “[The silverback] comes over, and he sits down, and he just waits for me to feed him. And it was beautiful. You get so worked up and then this happens. The primatologist says, ‘I’ve never seen him act this way.’ And I said, ‘Oh, so what you’re saying is I’m a man-and-a-half.’ She’s like, ‘No, probably because you’re really in tune with your emotions and you’re sensitive,’” Johnson recollected while laughing.

During his time at the charity, Johnson ended up adopting a male silverback gorilla, who just had a baby with the oldest gorilla whom they’ve ever observed giving birth. The female gorilla is also the last gorilla that Dian Fossey raised herself.

Watch more from The Ellen Show below, including a clip about why Johnson has a crush on Frances McDormand and a clip where Johnson and Ellen play a game called “Make It Dwayne.”