Videos of friendly, gentle foxes approaching humans, seemingly wanting to play, are going viral on TikTok. But just because a species is sociable doesn't necessarily make it domesticated.

In a video with over one million views on TikTok, a wild fox plays with what appears to be a ball, letting it roll down a hilly slope and chasing after it. The video is tagged #domesticatedfox. “He probably watched dogs playing fetch from afar,” one commenter writes. “He just wants to be a good boy too.” In another TikTok, a wild fox approaches a human’s outstretched hand. An enamored commenter jokes: "If not pet, why pet-shaped?"

A slew of viral videos on social media have many on the internet speculating that foxes are self-domesticating, meaning they have become more human-friendly over time without any explicit intervention or deliberate breeding.

But is it true? To be considered domesticated, an animal must experience both behavioral and physical changes; they grow tamer and often evolve to be smaller than the wild animal in some way. “The final clincher is the genetics,” Blake Morton, an animal behaviorist at the University of Hull in the UK, says. It not enough for one generation of an animal to show a softer side to humans. Those behaviors and traits must pass then down to their offspring.

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