August 20, 2012
Hormone levels for the female giant panda, Mei Xiang, are up, according to Zoo officials. This could mean a visit from the stork, or it could be another in a series of “pseudopregnancies,” according to the Zoo. Giant pandas are among the rarest animals in the world and the Zoo has worked with researchers to try to effectively breed more.
Mei Xiang has had five pseudopregnancies in a row and last gave birth July 9, 2005. After artificial insemination in April of this year, officials are hoping her only cub will soon have a younger sibling within 40 to 50 days. She has reportedly begun nesting.
Panda keeper Juan Rodriguez says Mei Xiang has been shredding bamboo and collecting it in a corner of her den since the beginning of August. He’s noticed other behavioral changes, including a slowness to react to his calls. “We don’t have a scientific name for it but spaciness is how we describe her behavior.” Eventually, he explains, she will not want to leave her den at all as the birth approaches.
Because of the many false alarms, Rodriguez says, “We try to stay subdued over here.”
The team began doing ultrasounds once a week about a month ago but the soonest an ultrasound can give a definitive answer (and even then, it’s not 100 percent) is two weeks prior to the birth. Visitors to the Zoo can see a bald spot on Mei Xiang’s abdomen from where her fur had to be shaved for the ultrasound. The team has also been tracking her hormones with weekly urine samples that will switch to daily in a few weeks. Rodriguez says they are treating it as a real pregnancy but that the team isn’t celebrating yet.
“That’s the thing with pseudopregnancies and real pregnancies, there’s really no difference,” he explains. The phenomenon of pseudopregnancies is something scientists are still asking questions about. Rodriguez says it could very well be part of their natural history or a result of environmental cues.
Even after hormone levels drop off in a pseudopregnancy, animals can still exhibit changed behaviors. Rodriguez says after last year’s false alarm, Mei Xiang continued nesting for several days.
Rodriguez says, “If she gives birth we’re ready to rock, but we also don’t want to get our hopes up too high.”
This post was updated at 1:23 p.m.
February 7, 2012
Our inquisitive readers are rising to the challenge we gave them last month. The questions are pouring in and we’re ready for more. Do you have any questions for our curators? Submit your questions here.
How much is the Hope Diamond worth? — Marjorie Mathews, Silver Spring, Maryland
That’s the most popular question we get, but we don’t really satisfy people by giving them a number. There are a number of answers, but the best one is that we honestly don’t know. It’s a little bit like Liz Taylor’s jewels being sold in December—all kinds of people guessed at what they would sell for, but everybody I know was way off. Only when those pieces were opened up to bidding at a public auction could you find out what their values were. When they were sold, then at least for that day and that night you could say, well, they were worth that much. The Hope Diamond is kind of the same way, but more so. There’s simply nothing else like it. So how do you put a value on the history, on the fact it’s been here on display for over 50 years and a few hundred million people have seen it, and on that fact it’s a rare blue diamond on top of everything else? You don’t. – Jeffrey E. Post, mineralogist, National Museum of Natural History
What’s the worst impact of ocean acidification so far?- Nancy Schaefer, Virginia Beach, Virginia
The impacts of ocean acidification are really just starting to be felt, but two big reports that came out in 2011 show that it could have very serious effects on coral reefs. These studies did not measure the warming effect of carbon dioxide in the atmosphere, but rather its effect of making the ocean more acidic when it dissolves in the ocean. Places where large amounts of carbon dioxide seep into the water from the sea floor provide a natural experiment and show us how ocean waters might look, say, 50 or 100 years from now. Both studies showed branching, lacy, delicate coral forms are likely to disappear, and with them that kind of three-dimensional complexity so many species depend on. Also, other species that build a stony skeleton or shell, such as oysters or mussels, are likely to be affected. This happens because acidification makes carbonate ions, which these species need for their skeletons, less abundant.
Nancy Knowlton, marine biologist
National Museum of Natural History
Art and artifacts from ancient South Pacific and Pacific Northwest tribes have similarities in form and function. Is it possible that early Hawaiians caught part of the Kuroshio Current of the North Pacific Gyre to end up along the northwest coast of America from northern California to Alaska? — April Amy Croan, Maple Valley, Washington
Those similarities have given rise to various theories, including trans-Pacific navigation, independent drifts of floating artifacts, inadvertent crossings by ships that have lost their rudders or rigging, or whales harpooned in one area that died or were captured in a distant place. Some connections are well-known, like feather garment fragments found in an archaeological site in Southeast Alaska that appear to have been brought there by whaling ships that had stopped in the Hawaiian Islands, a regular route for 19th-century whalers. Before the period of European contact, the greatest similarities are with the southwest Pacific, not Hawaii. The Kushiro current would have facilitated Asian coastal contacts with northwestern North America, but would not have helped Hawaiians. The problem of identification is one of context, form and dating. Most of the reported similarities are either out of their original context (which can’t be reconstructed), or their form is not specific enough to relate to another area’s style, or the date of creation cannot be established. To date there is no acceptable proof for South Pacific-Northwest Coast historical connections that predates the European whaling era, except for links that follow the coastal region of the North Pacific into Alaska.
William Fitzhugh, archeologist
Natural History Museum
January 23, 2012
The Smithsonian Institution today announced that it will delay the openings of all the Washington, DC area museums and the National Zoo until 11 a.m.
October 7, 2011
In August, at the National Zoo, the efforts of keepers and biologists finally came to fruition as two baby tree shrews were born. But because of the secretive rearing habits of the species, zoo staff had no way of knowing until nearly two months later, when the shrews were fully grown.
“One of the many things that’s interesting about them is the way they’re cared for as young,” says David Kessler, a biologist at the Zoo. “What happens is, as soon as they’re born, they’ll nurse, and they will drink up to 50 percent of their body weight in one nursing. Then they’re in a nest, and the female has her own nest separate from where they are, and she’ll only come and nurse the young once every 48 hours.”
This lack of contact means that the tiny babies—each one just six to ten grams in weight—are effectively hidden for their entire maturation period.
When the offspring finally emerged almost fully grown last week, Zoo staff learned that the plan put in place last spring as part of a nationwide population management plan was a success. “We have been very successful in the past breeding them, so it was recommended that we swap one of our castrated males for an intact male,” Kessler says. “The population in zoos all around North America is now 47, after the birth of these two.”
The National Zoo is now home to six of these fascinating small creatures. Despite their name, they are not true shrews, and are no longer classified as insectivores, but rather in their own order Scandentia. Native to southeast Asia and China, they can live in both tropical and temperate forests, at elevations up to about 10,000 feet.
“Even though they’re called tree shrews, not all of them live up in the trees all the time,” says Kessler. “They’ll eat fruits, vegetables and insect material. Here at the Zoo we feed them crickets, meal worms, wax worms, fruits and vegetables.”
Perhaps the strangest facet of tree shrew life is the symbiotic relationship they share with carnivorous pitcher plants in the wild. “They defecate in the pitcher plants—they use them like little toilets,” Kessler says. “The shrews get some food from being around the pitcher plants, and the feces of the tree shrew account for 57 to 100 percent of the plants’ nitrogen intake.”
The rapid maturation of the Zoo’s tree shrew babies is now nearly complete. “Their ears are open around ten days, their eyes at 20,” says Kessler. “They come out of the nest at around four weeks or so, and then they’re sexually mature within two to three months.”
Kessler reports that Zoo visitors can come see the shrew offspring, which are becoming more active each day. “They are on exhibit, and can be seen at the Small Mammal House,” he says. “They still do not emerge from the nest that much yet, but they’ll be out more and more frequently as the days go on.”
September 19, 2011
Monday, September 19 The Life of Cleopatra
Come learn about the life of Cleopatra through a discussion with her Pulitzer Prize-winning biographer Stacy Schiff. Cleopatra: A Life, Schiff’s latest bestseller, sheds new light on the world of ancient Egypt and its royal court. Along with Lynn Neary, NPR’s arts correspondent, Schiff will discuss the work that went into the book and the widespread fascination with Cleopatra that she shares with her readers. Schiff will be signing books after the program. $15 for Smithsonian Resident Associates, $20 for general public. 7 to 8:30 p.m. Natural History Museum, Baird Auditorium
Tuesday, September 20 Aldabras Galore
What’s an Aldabras? Native to the Seychelle islands in the Indian Ocean, they’re some of the biggest tortoises in the world. Visit the Zoo to see and learn about the resident Albadras from the caretakers as they move them from their outdoor habitat into the Reptile House for the night. Free. 4 p.m. daily. National Zoo, outside Reptile House
Wednesday, September 21 Celebrate the Land
Shout, a Smithsonian education program designed to help students worldwide take an active role in environmental issues, hosts the online seminar “Celebrate the Land.” Students and teachers can join Smithsonian experts to discuss the U.S. Forest Service (11 a.m.), learn about environmental trends observed from satellite images (1 p.m.), hear about the Smithsonian Tree Banding program (2 p.m.) and ask curators their own questions (3 p.m.). Seminars are online only. This event is free, but online registration is required.
Thursday, September 22 La Buena Vida
Writer, educator and folklorist Fabiola Cabeza de Baca‘s legendary radio broadcasts of the 1930s and 40s were a home for discussion of agriculture, home economics, personal stories and other aspects of rural New Mexican life. At this Historic Theater event, relive and participate in the broadcasts, learning about Ms. Cabeza de Baca’s stories while sharing some of your own. Free. This event will begin on Sept. 22 and be held on most Thursdays through Sundays, at 11 a.m, 1, 2:30, and 4 p.m. American History Museum, meet at 1st floor visitor center.
For a complete listing of Smithsonian events and exhibitions visit the goSmithsonian Online Visitors Guide. Additional reporting by Michelle Strange.