Dexter, a 6-year-old Brittany Spaniel dog, has become famous for his ability to adapt by learning to walk only on his hind legs, after losing one of his front legs in a car accident.

Dexter hadn’t even turned 1-year-old when he broke out of his owners’ yard in Ouray, Colorado to follow a scent. Focused on his goal, the pup accidentally ran out in front of a moving van and got hit pretty badly. Luckily, he was found moments later by his owner’s husband, Tim Pasek, who immediately took him to a vet. One of his front legs had to be removed, and the other turned out to be more badly damaged than originally thought. But the important thing is that after a 45-minute procedure, Dexter’s life was saved, and he has since adapted perfectly, relying only on his hind legs to get around, just like a human.

“We took him 45 minutes to the vet, his vet saved his life,” Dexter’s owner, Kentee Pasek, told Newsweek. After his first surgery and rehab at home, we found out the remaining leg was more injured than previously thought. During this time the front leg was not weight-bearing so Dexter taught himself to walk upright!

It all started one day, two months after Dexter’s accident, when his owners took him outside on the front lawn and he simply got up on his hind legs and walked up onto the porch like a human. Kentee and her husband were worried that he might fall and hurt himself again.

Dexter’s remaining front leg was badly damaged after the accident, so his owners bought him custom wheels so he could get around easier. He used them a bit at first, but then one day he got up on his hind legs again, with the wheels hanging from his stomach as if to say he didn’t need them anymore. He’s been bipedal ever since.

“My reaction was pure shock and disbelief I called the vet and it was decided Dexter was safer to walk upright if he wished without the wheels then to walk upright with them attached,” Kentee Pasek said.

Dexter’s ability to adapt and use his hind legs exclusively whenever he wants to move around fast has turned him into an online sensation. Videos posted by his owners to TikTok, Instagram and other social media platforms regularly go viral, with some registering millions of views.

While most of the feedback on Dexter’s videos is positive, there are some who express concern about the strain on the dog’s back and his hind legs. However, Kentee pointed out that Dexter undergoes regular checkups, and that the real concern is the remaining front leg, which is very weak and also causes Dexter a lot of pain when the barometric pressure changes.

“He’s developed massive, weight-lifter thighs. It was his desire to adapt,” Dexter’s vet told the Denver Post. He chose two legs. They didn’t make him walk on two legs. He accepted that he has this adversity and that he’s not going to let it get him down. He has amazing resilience.”

Dexter’s owners hope that he will be able to live a long and happy life, and they pray that he will be able to continue walking upright without developing serious conditions like hip displacement. But whatever happens, they’re just lucky to have him.

“We are grateful to still have Dexter in our life. We did not know if he would make it past the first night, first surgery, then all of the other surgeries,” Kentee Pasek said. “We did not know if we would have him a day, week or month. The vet said he might last four years like this and now in April, he will turn seven years old!”