Because once they are found with modern animals they stop being prehistoric. Think, coelacanth.
Or, better... find *one* single example of say, dinosaur fossils. . .
Can you give me an example of a walrus remain found in the same strata as that of a camel?
Disprove radiometric dating for once and for all and replicate labatory conditions where it will give completely wrong results.
fChristian posted an interesting article by Richard Milton in post 44 describing problems relating to radiometric dating of fossils specifically the potassium-argon method. I'm interested in your opinion.
If/when that happens, it will be dismissed as some other kind of artifact. Assuming some kind of YEC and not an OEC.