I have a dictionary with the tongue map printed in it. It's also in a Magic School Bus book.

It's a good case study in society's ability to believe things despite the fact that every single individual in the society has direct personal experience falsifying the belief. If you've ever eaten candy, you've experienced the taste of sugar all across your tongue.

It takes only a couple of seconds to run an experiment that conclusively disproves the tongue map. But there it is in the reference books.

(Related: one of Phil Plait's pet peeves is apparently the large number of people who tell him that you can't see the moon during the day. Again, all it takes to falsify this belief is occasionally looking up.)

Certain taste receptors are enriched in different areas of the tongue, but there are no exclusive zones.

> all taste sensations come from all regions of the tongue, although different parts are more sensitive to certain tastes