Smithsonian scientists got a surprise glasnost gift from Soviet scientists attending a conference here this week -- some shaggy, 30,000-year-old hair samples from two extinct species, a woolly mammoth and a woolly rhinoceros that were discovered frozen in the Siberian permafrost.

The rhinoceros hair is the first such specimen to leave the Soviet Union, said Dennis Stanford, a curator of archaeology at the National Museum of Natural History. The mammoth specimens, which also included preserved stomach contents that give clues to the animal's diet, are the first material from a frozen mammoth the museum has received, he said.

Stanford said Smithsonian researchers were excited about the research possibilities of the gift. He said they will try to extract segments of genes from the samples in order to learn how closely the animals were related to existing elephant and rhinoceros species and to extinct mammoth and mastodon species that lived in North America.

Soviet paleontologist N.K. Vereshchagin of the Leningrad Academy of Science surprised Stanford on Wednesday with the news that he had brought the specimens to Washington. Vereshchagin was attending a conference of the International Council for Archaeozoology that is taking place at the Smithsonian this week.

"They have a lot of these things and we don't have any," Stanford said. "He thought it would be good if American researchers could have these to look at. We had no idea he was going to do it."

Stanford said the two-foot-long hank of mammoth hair "looks like you took a young lady with nice long, blond hair and cut off her pigtail."

He said researchers believe mammoths' hair was really reddish-brown, but that preserved specimens have lost some of their pigment over time.

He said the woolly rhinoceros hair looks similar but is only about five inches long.

Woolly mammoths and woolly rhinoceroses lived on the frigid steppes of the northern hemisphere during the late Ice Age or Pleistocene, which lasted from about 70,000 years ago until about 10,000 years ago. Researchers believe they became extinct at the end of that period because of global warming, which dramatically changed the habitat and reduced the availability of plants they ate.

Studies by Soviet researchers of preserved stomach contents indicate that mammoths ate grasses, mosses and twigs of trees such as willows, alders and birches.

Their long hair kept them warm through the severe, relatively snowless winters and their 12-foot-long tusks helped them break through ice to find water.

With warming of the climate at the end of the Ice Age, snowfalls became heavier and grasslands gave way to forests and swamps. A diminished food supply may have made the animals more vulnerable to predators like wolves and cave lions, Stanford said.

Climate changes also may have affected their fertility. Researchers suspect a female woolly mammoth probably had a calf only about once every 10 years.

Frozen woolly mammoths have occasionally been found in the Western hemisphere, but frozen woolly rhinoceros carcasses have been discovered only in Siberia, Stanford said.