Not everyone is a fan of sour-tasting things, but the fact is that sour may actually be the oldest taste.

In the video above, host Kallie Moore talks about how sour might be the oldest taste of all. Sour taste was originally to alert animals to danger, but for some creatures, including humans, sour taste evolved into something to be enjoyed.

Take a look at the video above and watch Moore explain how it all happened.

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