At the Zoo

Mei Xiang, Jessica Siegal-Willott, Juan Rodriguez Jessica Siegal-Willott, right, supervisory veterinarian, performs an ultrasound on giant panda Mei Xiang, as animal keeper Juan Rodriguez feeds the panda apples and pears at the National Zoo in Washington, Thursday, March 24, 2011. "She's looking great," says Siegal-Willott. "It's too early to say if she's pregnant or pseudo-pregnant but she's progressing normally for both." Mei Xiang was artificially inseminated in January, and is now having weekly ultrasounds to monitor her condition. (AP Photo/Jacquelyn Martin)

AP Photo/Jacquelyn Martin

Coming Out Two of the seven lion cubs born at the National Zoo are greeted by their mother at the Smithsonian's National Zoological Park in Washington Saturday, Dec. 18, 2010, the day of their public debut. (AP Photo/Jacquelyn Martin)

AP Photo/Jacquelyn Martin

Lion Cub A lion cub checks out some snow as the seven lion cubs, born of two lionesses at the National Zoo, make their public debut at the zoo in Washington, on Saturday, Dec. 18, 2010. (AP Photo/Jacquelyn Martin)

AP Photo/Jacquelyn Martin

National Zoo Shylin, Belle, Jaelyn, and JT at the Zoo.

Bored Lion Lion at the washington D.C. zoo

Very Hungry Panda Panda eating bamboo at D.C. zoo

National Zoo Here's one of the National Zoo's birds. (WTOP Photo/Michelle Basch)

WTOP Photo/Michelle Basch

Panda Play At National Zoo a panda plays with a blue ball.

Moving Dinosaur Uncle Beazley This handout photo provided by the National Zoo shows workers removing "Uncle Beazley," the life-size fiberglass triceratops, Wednesday, Feb. 16, 2011, at the zoo in Washington. The life-size fiberglass triceratops was moved to the Smithsonian's Office of Exhibits Central in Landover, Md. to have his holes and cracks patched. It will also receive a new coat of UV and weather resistant paint. "Uncle Beazley" is named after a dinosaur in the children's book The Enormous Egg, by Oliver Butterworth, and the movie adaptation, in which the statue appeared. Louis Paul Jonas created the Zoo's Uncle Beazley statue in 1967. It was subsequently donated to the Smithsonian by the Sinclair Company. (AP Photo/Mehgan Murphy/Smithsonian's National Zoological Park)

AP Photo/Mehgan Murphy/Smithsonian's National Zoological Park

Mei Xiang, Juan Rodriguez

Mei Xiang, Juan Rodriguez Animal keeper Juan Rodriguez feeds giant panda Mei Xiang apples and pears as an ultrasound is performed on her at the National Zoo in Washington, Thursday, March 24, 2011. "She's looking great," says supervisory veterinarian Jessica Siegal-Willott. "It's too early to say if she's pregnant or pseudo-pregnant but she's progressing normally for both." Mei Xiang was artificially inseminated in January, and is now having weekly ultrasounds to monitor her condition. (AP Photo/Jacquelyn Martin)

AP Photo/Jacquelyn Martin

Cheetah Cubs This July 12, 2011 image provided by Smithsonian Conservation Biology Institute shows five cheetah cubs born May 28 at the National Zoo’s Smithsonian Conservation Biology Institute in Front Royal, Va. The cubs received their first health exam July 12, 2011 and are healthy and thriving. (AP Photo/Smithsonian Conservation Biology Institute/Lisa Ware)

AP Photo/Smithsonian Conservation Biology Institute/Lisa Ware

Ohio Zoo Fishing Cat Three Fishing Cat kittens are seen at the Columbus Zoo and Aquarium on Tuesday, Aug. 16, 2011. Born on July 29, the three kittens are being cade for at the zoo by their mother in a secluded den. In the wild, the nocturnal fishing cat is found in southern Asia in densely vegetated areas near marshes, mangroves, rivers and streams as well as in tropical dry forests. (AP Photo/S.J. Grahm, Columbus Zoo and Aquarium)

AP Photo/S.J. Grahm, Columbus Zoo and Aquarium

Ohio Zoo Fishing Cats One of three Fishing Cat kittens is seen at the Columbus Zoo and Aquarium on Tuesday, Aug. 16, 2011. Born on July 29, the three kittens are being cared for at the zoo by their mother in a secluded den. In the wild, the nocturnal fishing cat is found in southern Asia in densely vegetated areas near marshes, mangroves, rivers and streams as well as in tropical dry forests. (AP Photo/S.J. Grahm, Columbus Zoo and Aquarium)

AP Photo/S.J. Grahm, Columbus Zoo and Aquarium

ST. JOSEPH'S HOSPITAL AND MEDICAL CENTER OLDEST MANDRILL The oldest mandrill in the United States, Wucaria, 34, enjoys a day in the sunshine at the Phoenix Zoo after a delicate kidney operation that was performed by the zoo's veterinarians and one of the nation's top "human" heart surgeons. Harvard-trained Dr. Brian deGuzman of Phoenix's St. Joseph's Hospital was tapped to help perform the life-saving surgery. (PRNewsFoto/St. Joseph's Hospital and Medical Center; Phoenix Zoo, Ryan Dimal)

Germany Zoo New-born golden-bellied capuchin named Pinu'u sits on the back of his mother Ibama in their enclosure in the Cologne zoo, Germany, Thursday Aug. 11. 2011. Pinu'u was born on July 4, 2011. (AP Photo/dapd/ Timur Emek)

AP Photo/dapd/ Timur Emek

Mei Xiang is back in her panda habitat on Marfch 31 after her second round of artificial insemination took place during the weekend. (Courtesy Smithsonian National Zoo)

Courtesy Smithsonian National Zoo