Generally people tend to overlook the fact that ERV remnants are found in identical locations in the genome. When I look at the Creationist/ID interpretation of the data the responses range from vague ("Similarity doesn't mean relationship!") to the fact that they conveniently ignore the identical insertion loci fact ("Hey two animals can have the same mutation without being related!").
EVR remnants are one of the best and most direct evidences for common descent, and it's quite frustrating to have to deal with people who blatantly ignore evidence (though this could be from my bias as a geneticist. When it comes to C14 or other things at the very least Creationists try to rationalize and throw up a wall of tripe. You can tear down tripe, you can fight tripe, you can even stew it in delicious broth until tender.
But when it comes to ERVs you can't make much progress in dispute... you can't debate someone who's tuned themselves out from facts.
In any case, if anyone can provide direct sources on ERVs I'd be much obliged. I can look them up at the university networks on Monday.
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