Cavemen, born of insurance commercials, plummeted in the ratings last night, down about 20 percent from its series debut last week. Cavemen's numbers last week were promising, but I, like many others, were suspicious that the ratings would be inflated for that first episode simply out of curiosity. Everyone I knew was at least a little curious how Cavemen turned out, how ABC turned an ad campaign whose star was make-up into a half-hour comedy/satire on racism. It's a crazy experiment by ABC and, to be fair, the reaction was mixed. No one appeared to love Cavemen, but a significant amount of viewers liked it. I think the most common reaction to Cavemen was that it wasn't a total disaster. This may be reflected in the week to week ratings.