Your rhetorical question makes about as little sense as asking, "If the Moon is made of green cheese, why weren't the Apollo astronauts covered in cheese when they returned to Earth?"
No "dinosaur bones" were ever found in the La Brea tar pits.
I seriously recommend that you refrain from engaging in scientific conversations until you have "brushed up" on your 8th-grade "Natural Science" curriculum. Making bold assertions and posing provocative rhetorical questions based upon half-remembered tidbits from junior high school - tarted up with factoids gleaned from repeat-viewings of "Jurassic Park" - is no way to go through life, FRiend!
Regards,
I shudda read ahead.
Freaky fondue fetish is frequently found in France; not Florida.
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