World and Nation

Shorts (right)

New view of how humans

moved away from apes

Anthropologists studying living hunter-gatherers have radically revised their view of how early human societies were structured, a shift that yields new insights into how humans evolved away from apes.

Early human groups, according to the new view, would have been more cooperative and willing to learn from one another than the chimpanzees from which human ancestors split about 5 million years ago. The advantages of cooperation and social learning then propelled the incipient human groups along a different evolutionary path.

Anthropologists had assumed until now that hunter-gatherer bands consist of people fairly closely related to one another — much as chimpanzee groups do — and that kinship is a main motive for cooperation within the group. Natural selection, which usually promotes only selfish behavior, can reward this kind of cooperative behavior, called kin selection, because relatives contain many of the same genes.

The new data on early human social structure furnishes the context in which two distinctive human behaviors emerged, those of cooperation and social learning, Kim S. Hill of Arizona State University said.

—Nicholas Wade, The New York Times

Number of cancer survivors

in US rises by 20 percent

About one in every 20 adults in the United States has survived cancer, including nearly one-fifth of all people over 65, according to new federal data.

The numbers, released Thursday by the Centers for Disease Control and Prevention and the National Cancer Institute, indicated the number of cancer survivors increased by about 20 percent in just six years, to 11.7 million in 2007, the latest year for which figures were analyzed, from 9.8 million in 2001. In 1971, the number of cancer survivors was 3 million.

About 65 percent of cancer survivors have lived at least five years since receiving their diagnosis, 40 percent have lived 10 years or more, and nearly 10 percent have lived 25 years or longer.

Dr. Thomas Frieden, director of the CDC, said the increase in cancer survivors was due to several factors, some of which varied by type of cancer. In some cases of breast cancer and colon cancer, for example, improved treatment and increased follow-up after treatment have helped increase survival. In others, like prostate cancer, an explosion in screening has identified many men with the disease, but the cancer is often so slow-growing that they would be unlikely to die from it in any case.

—Pam Belluck, The New York Times

White House announces

steps against Gadhafi

The White House announced Thursday a five-point program of steps to isolate Moammar Gadhafi and ultimately drive him from power, all stopping well short of military action, but distanced itself from the assessment of the nation’s top intelligence chief, who said Thursday that “over the longer term” Gadhafi’s superior firepower “will prevail” over the opposition.

The steps announced include a partial embrace of the opposition movement as well as threats to track and prosecute, in international courts, loyalists to Gadhafi who commit atrocities. Secretary of State Hillary Rodham Clinton said she would meet with Libyan opposition leaders next week, and President Barack Obama’s national security adviser made it clear that Washington was looking for ways to aid the Libyan leader’s opponents.

“We’re coordinating directly with them to provide assistance,” said the adviser, Thomas E. Donilon, although the United States has stopped short of recognizing them as the legitimate government of Libya.

The help, he added, consisted of humanitarian aid and advice on how to organize an opposition government.

—David E. Sanger, The New York Times

Startups rush to bring chat rooms to smart phones

For all the clever things smart phones can do these days — like stream movies and play 3D games — the latest mobile craze centers on revamping one of the earliest phone applications, the text message.

Apps from a wave of new startups allow multiple people to participate in the same conversation on a mobile phone, like a group chat room or conference call held by way of text message. The new applications, most of which are free, include GroupMe, FastSociety, Beluga, Kik, TextPlus, PingChat, HurricaneParty, and Yobongo.

Several of these services have made their debuts just this week, right before the opening on Friday of South by Southwest, the technology and music festival in Austin, Texas. They hope to gain some attention at the festival, which attracts scores of technology enthusiasts, entrepreneurs, and venture capitalists interested in seeing the latest innovative ideas.

Caleb Elston, one of the founders of Yobongo, which is based in San Francisco, said the timing of the app’s release, a week before South by Southwest, was “no accident.”

“It is the perfect storm of developers, designers, and business people in a sphere where there is a natural social dynamic for networking,” he said. “Lots of services already help you connect with your friends, but the point of South by Southwest is to meet with new people that have your interests.”

The services are a little different from one another. GroupMe, Beluga, Kik, TextPlus, and PingChat all allow people to create groups and invite their friends to chat in a group session. HurricaneParty performs a similar function but with the specific goal of organizing a party or get-together. Yobongo allows its users to join a group chat with nearby people.

—Jenna Wortham, The New York Times