The awkward reason why a zoo couldn't breed two hyenas

A zoo in Japan has finally realised why two of its hyenas had not managed to successfully reproduce - they are both male.

ITV News reports Maruyama Zoo in Sapporo had been given the hyenas, Kami and Kamutori, in 2010 by a South Korean zoo and were told they were a male and female pair.

After four years of attempting to mate the pair, the Zoo conducted a gender test and realised the mistake. A statement from the zoo explained the "the external genitalia of the male and female are similar" in hyenas.

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