Japanese zookeepers didn't understand how Momo, a 12-year-old white-handed gibbon, managed to get pregnant when there were no boy monkeys in the cage. When they performed a DNA test on her baby, they learned the father was Itō, a 34-year-old agile gibbon, who lives in an adjacent enclosure.
"Agile" turns out to be an apt description for wily Itō: "The zoo told CNN on Friday it believed that Momo and Itō had managed to mate through a small hole in a steel plate between their enclosures. The hole measured about 9 millimeters (0.3 inch) in diameter."
The lesson here: where there's a willy, there's a way.
The baby has not yet been named. I suggest "Glory."