A zoo in Japan just made a surprising discovery about one of their hippos after seven years…
…It is a girl.
The Osaka Tennoji Zoo says its documentation listed the 5-year-old hippo Gen-chan as male when it took her in.
However, zookeepers began to notice she did not take part in typical male hippo behavior, such as courting females or marking its territory by defecating and whipping its tail.
They eventually ordered a DNA test that confirmed Gen-chan was a she.
The zoo says her documentation will be changed, but the name will not be changed.