Here's an extraordinary story from a friend of mine, who was attending the Discovery seminar in Jerusalem a while ago, and was surprised to hear the lecturer telling over the animal argument.
"He finishes his presentation of the 4-animals proof and he concludes this is rock-solid proof that God gave the Torah. He doesn't mention any of the glaring problems with the theory and he doesn't mention your book [The Camel, the Hare and Hyrax.]
When I asked him to address some of the issues raised in your book he simply dismissed my question by saying there are zoological (i.e. factual) problems with the claims in your book. I asked for an example and he said he couldn't think of one on the spot but that he would email them to me later. [He never did even though I emailed him repeatedly asking for them.] Then I said to him: It sounds to me, from the way you are characterizing Slifkin's book, that you never actually read it. Did you?
Unbelievably, he says no. I said to him, in front of the whole class: Your whole job in life is to prove the Torah is divine using the 4 animals proof. Rabbi Slifkin writes a book that shows the proof is faulty and you don't even bother to read the book?! Forget about your lack of intellectual honesty, where is your curiosity?
Later, a senior Discovery person told me that they had an in-house Aish seminar for Discovery lecturers and they decided that Slifkin's book was problematic."
Needless to say, Discovery has never published any kind of rejoinder to my book, nor have they ever published any comprehensive study of the topic and explanation of how it works as an argument. Unless you count the two-page discussion in "Eye of a Needle," which, as I showed in my book, is rife with errors and distortions from beginning to end. I challenge them to find a single zoological or other factual error in my book, let alone one that undermines its conclusions!
I want to conclude by noting that one should not extrapolate from some Aish educators to others. I have been contacted by other Aish educators who congratulated me on my work and promptly stopped using the animal argument. Yasher koach to them!