But mules can only be born when a male donkey and a female horse mate; crossing a male horse with a female donkey results in a different hybrid called a hinny, which is rarer. The hybrid vigor of ...

The first pony of the season has been born at a nature reserve. The Konik filly - female foal - arrived 10 days ago at the National Trust's Wicken Fen National Nature Reserve in Cambridgeshire.