(CBS News) It's been 40 years since China sent the first pair of Pandas to the U.S. as a way to warm international relations between the two countries.
All eyes have turned to a pair of pandas at the Smithsonian National Zoo in Washington where zookeepers, the public and the media anxiously await news of a potential to the panda family.
Mei Xiang, the zoo's female panda, may be pregnant. But it'll take 40 days or so to be sure. If she doesn't reproduce, she could be shipped back to China and replace by a younger, more fertile alternative.
"There's a possibility that she will not be here next year if she's not successful and producing a cub this year," said Nicole McCorkle, the panda's keeper.
Mei Xiand and her partner Tian Tian came to Washington in 2000, and have had just one cub, and seven false alarms since.
"Neither one of them had breeding experience when they got here," McCorkle said. "And then on top of that, the females are only really fertile for 24 or 48 hours, so it's really important that all efforts are concentrated in that time."
Tian Tian doesn't seem to have a clue how to mate, so the zoo resorted to artificial insemination. The news that Mei Xiang is beginning to act pregnant, by building a nest in her den out of the view of visitors has gotten people excited.
All mating pairs of pandas in the U.S. are from China. They're the current generation of what 40 years ago was called the "panda diplomacy," the first thaw in the Cold War between the U.S. and China.
The thaw began in 1973 when President Richard Nixon opened the door to China, and the U.S. began do deal directly with Beijing's communist government.
The first panda pair, Hsing-Hsing and Ling-Ling were a gift from China, welcomed to the zoo by First Lady Pat Nixon. The pandas set off a wave of interest in the creatures around the country.
The zoo estimates that in the more than twenty years Ling Ling and Hsing Hsing were alive, 75 million people came to see them.
"Those big colorations around their eyes seem to naturally attract both children and adults. And it's secretive," zoo director Dennis Kelly said. "It wasn't even that well known even to the Chinese."
The public's fascination with pandas also seems to have saved them from extinction. "The work that the American zoos and the zoos around the world have done with the Chinese over the last 40 years have really turned this species around," Kelly said. "From almost going extinct to now having hope that a now iconic species like the giant panda will survive."