Ferrel pigs, allowed sufficent generations in the wild, without significant reintroduction of domestic stock, will slowly revert to their ancestry. Kind of like reverse breading. Just as the wild boar was bread into the domestic pigs of today, domestic pigs in the wild will, over time will, unbread....so to say.
We see it in the wild pigs here in Florida. The longer a population of pigs goes without a introduction of new domestic stock the more like wild boar the will become. With each successive generation they will be longer haired, more of them will be black, their legs will be relatively longer, their snouts narrower and longer, and the boars will develop VERY thick shields and significant tusks.
Even their habits will change. They will graze more and root less.
