Betrayed by its DNA and unmanly toilet habits, a hippopotamus in Japan thought for seven years to be a he is in fact a she, the zoo where the wallowing giant lives said Tuesday.
The 12-year-old came to Osaka Tennoji Zoo in 2017 from the African Safari animal park in Mexico, where officials attested on customs documents that the then five-year-old was male.
But zookeepers long scratched their heads, a spokeswoman told AFP.
In particular, Gen-chan did not display the typical male hippo behavior of splattering feces around while defecating -- with a propeller-like tail motion -- in order to mark territory.
Nor did it make courtship calls to females and zookeepers were unable to visually identify any male genitalia, a dangerous task in such a large and potentially aggressive beast.
"Therefore, we requested a DNA test at an external institution, and the result showed it was female," the zoo said in a statement posted last week.
"We will keep doing our best to provide comfortable environment to Gen-chan, so everyone, please come and see," it said.
