Jon Ronson and the Quest for the Aryan Cow, Radio 4

Hitler's grand designs weren't restricted to the human race. Flora and fauna were fair game too, and he had high hopes for the aurochs, a huge beast which was the ancestor of today's domestic cattle.

Inconveniently for Adolf, it had been hunted to extinction by the early 17th century, but the Third Reich geneticists Lutz and Heinz Heck attempted to breed it back into existence by mixing'n'matching animals from the Highlands, Corsica and the Camargue, and so Jon Ronson took off in search of the Nazis' sacred cow.

Ronson, who's Jewish, isn't exactly a fan of eugenics. "My philosophy is, like, the plucky nerdy underdog is what's right about the world," he said. We joined him tramping gingerly across a frozen lake – "It doesn't look very frozen to me" – in a private zoo near Munich where Gregor Frisch and his father carry on the work of the Heck brothers.

Gregor had been bigging up the aurochs – "something very mighty", he said. But Ronson, who comes over as a brainier version of Louis Theroux, was disappointed. "They're not as big as I thought they'd be," he muttered. "Oh gosh, are they going to stampede? I would have thought the sight of 14 aurochs running towards me would have been one of the scariest things I'd ever seen, but not really – they look like little, erm, black things."

Gregor sounded deflated: "We haven't seen the one I'd like to show you." But as Ronson pointed out, they're not aurochs at all, literally speaking. (Technically they're called Heck cattle.) "It's like mating a lizard with a toad and hoping to get a dinosaur," he said. Not exactly what Hitler had in mind, I would have thought.