Science: It's a Geep

Crossbreeding goats and sheep

It looks like a zookeeper's prank: a goat dressed in a sweater of angora. But the odd-looking creature that appeared on the cover of the journal Nature last week is no joke. The animal is a crossbreed of two entirely different species, a goat and a sheep. Inevitably, it has been dubbed a geep.

Now 18 months old and thriving, the geep was produced by the latest tricks of embryo manipulation. Scientists at the Institute of Animal Physiology in Cambridge, England, mingled new embryos from both sheep and goats when each consisted of no more than four to eight...