Deep breath. Accelerator mass spectrometry and radiocarbon testing reveal that the Capitoline She-Wolf, Lupa Herself, was cast in bronze in the 11th or 12th century. A.D. or C.E., whatever your preference. Yep. (Who knew that bronze casting left organic residue that could be radiocarbon dated? Wait a minute: what's the deal with that? Does residue date the entire object?)
Compromise theory: medieval copy of Etruscan original. Sure. Whatever.
Hey, why'd we ever think it was Etruscan to begin with? Winckelmann said it was, based on (you guessed it) stylistic analysis.
Can we stop listening to him now?