I'm guessing it's a joke: http://en.wikipedia.org/wiki/Wildebeest http://en.wikipedia.org/wiki/Wildebeest And "unixen" refers to the weird english "ox / oxen"

I'm guessing it's a joke: http://en.wikipedia.org/wiki/Wildebeest http://en.wikipedia.org/wiki/Wildebeest And "unixen" refers to the weird english "ox / oxen" pluralization. GNU's not Unix, but they're similar because they're both hoofed mammals.