In a mysterious bit of monkey business, a female at a chimpanzee sanctuary has given birth, despite the fact that the facility's entire male chimp population has had vasectomies.

Now managers at Chimp Haven are planning a paternity test for the seven males who lived in a group with Teresa, a wild-born chimpanzee in her late 40s who had the baby girl last week.

Workers have started collecting hair samples from the chimps for testing. Once they identify the father, it's back to the operating room for him.

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Chimp Haven managers said they knew something was up when Teresa was missing during morning rounds on January 8. Later in the day, she appeared with a newborn chimpanzee in her arms.

"Well, we were all just a little bit surprised when we heard the news," said Linda Brent, a spokeswoman for Chimp Haven.

The baby chimpanzee was named Tracy and she and her mother are doing fine, Brent said.

Teresa had 10 other offspring before retiring to Chimp Haven over a year ago. This is her first baby in 13 years.

It's also the first chimpanzee born at the sanctuary although officials there hope there will be no more accidents.

Chimp Haven provides long-term care for chimpanzees who are no longer needed for laboratory research. It was established by a group of primatologists and is located on 200 forested acres about 20 miles southwest of Shreveport. The first chimpanzee residents began arriving in 2005, according to the sanctuary's Web site.

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