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human
ELI5: Why do panda bears have fangs like carnivores when all they eat is bamboo?

I was wondering if their carnivor-like teeth wouldn’t wear because of eating all that bamboo. 
Wouldn’t it be easier for them to have the same teeth as for example rodents?
gpt
They used to be carnivores. Depending on your definition, they still are. They're in the order *Carnivora* and the family *Ursidae*. Their closest living relatives are black bears and brown bears. Pandas are the only species in their subfamily, having split off from the subfamily *Ursinae* (which includes black, brown, and polar bears) a long time ago. Nonetheless, they are true bears.

They just haven't had enough time or evolutionary pressure to lose their canine teeth.

Eating bamboo was likely the result of loss of prey species millions of years ago and an empty niche for a large animal eating plentiful bamboo. So, they moved to the mountains and filled that niche. Pandas also lack other traits common with herbivores like multiple stomachs and a long intestinal tract to break down plant matter. That's ok because the inside of bamboo is *relatively* easy to digest (still harder than meat), and they just eat a **ton** of bamboo to make up for their inefficiency at extracting what little nutritional value exists in bamboo.