One morning in January 2011, Dr. Larry Ammann, a professor of statistics at UT Dallas, discovered a mysterious stranger in his back yard.

Two years later, that stranger’s identity is not only known, it’s also been shared with millions of people thanks to a popular TV game show.

Ammann, who has been a faculty member in the School of Natural Sciences and Mathematics since 1975, is an avid nature photographer. In 2011, he spotted a female northern cardinal at a bird feeder at his home in Dallas.

The species is common in North Texas year round, but Ammann noticed something unusual about this particular bird. Its coloring was a dull brown like a typical female cardinal, yet it had the male bird’s characteristic red crest atop its head.

“When the bird turned around, I saw it had bright red male coloring on the other side,” Ammann said.

Intrigued with the half-n-half bird, Ammann immediately went for his camera. He was able to get one shot of the cardinal that day. Fortunately, he said, the bird remained in the neighborhood and he was able to capture additional images.

After doing some research and querying experts with the National Audubon Society, Ammann determined that his visitor was a rare bilateral gynandromorph – an animal exhibiting both male and female characteristics, typically split down the middle of the body.

Bilateral gynandromorphs are the result of a genetic mistake that occurs in the earliest cell divisions after an egg cell is fertilized. That error results in the animal developing with one side of its body female, the other side male.

The appearance of a gynandromorph is particularly striking in species like the northern cardinal, where the male is very brightly colored and female is much more drab.

I saw it briefly in February 2013, but then it started visiting my feeder occasionally this summer. That means this bird survived the record heat and drought during the summer and fall of 2011 and it survived in an area that is actively hunted by Cooper’s Hawks.

Dr. Larry Ammann,
professor of statistics at UT Dallas

In May 2011, Discovery News ran an online story about Ammann’s discovery. Then, in May of this year, Ammann was contacted by the TV quiz show Jeopardy! about using one of the photos he posted online of the gynandromorph cardinal. In the popular long-running game show, contestants are presented with clues in the form of answers and must phrase their responses in the form of questions. Ammann’s photo appeared in an episode that aired July 16.

During the Double Jeopardy round, the picture of Ammann’s bird was shown and the contestant was expected to know that “gynandromorph” means an animal that is both male and female.

The bird’s appearance on Jeopardy! coincides with its reappearance in Amman’s yard. After a nearly two-year absence, the cardinal is back, Ammann said.

“I saw it briefly in February 2013, but then it started visiting my feeder occasionally this summer,” he said. “That means this bird survived the record heat and drought during the summer and fall of 2011 and it survived in an area that is actively hunted by Cooper’s Hawks.”

Ammann continues to take photos of the bird, whose behavior seems more male-like than female, he said. Only a genetic test can determine the actual gender of the bird, but to date Ammann has been unable to acquire any of its feathers, let alone a blood sample.

“The other male cardinals in the yard try to chase it away, but the females tend to ignore it,” Ammann said. “Unfortunately, the gynandromorph cardinal does not seem to sing, so I just have to watch for it.”