Leaping into the air, she looks like something from the funny farm. But this curious creature is making scientists do a double-take. Meet Lisa the geep... a cross between a goat and a sheep.

She was born after an unscheduled amorous encounter on the farm of Klaus Exsternbrink, in Schwerte, in northern Germany's Ruhr Valley. One of his young billy goats leapt over a fence and had a passionate liaison with a ewe.

The result a month ago was Lisa - resembling a lamb in shape and stature, but with the colouring and agile back legs of a goat. Her mother seems unfazed by her unusual offspring and has raised her happily so far.

Now Lisa is booked into a specialist animal medical school in Hanover for genetic tests to determine her hybrid status. "These whims of nature are extremely rare," said the school's Professor Karl-Heinz Waldmann.