Evolution

If Vice President Biden continues to appear in public during this campaign, White House press secretary Jay Carney should be offered a membership in the janitors' union. As things stand, the spokesman does not have the supplies to clean up the mess Biden made Sunday on NBC's Meet the Press. Biden gave his full support to same-sex marriage, a position conspicuously at odds with the public stance of President Obama, who is widely assumed to share Biden's view but says his thinking is "evolving.

Our highly social species has been behaving strangely of late, and this has been noted in a flurry of recent hand-wringing articles wondering whether technology is changing our nature. The cover of the Atlantic asks whether Facebook is making us lonely, and the New York Times bemoans "The Flight From Conversation. " The authors observe what many of us have experienced: Friends invite us to get together only to spend the time texting other friends or tweeting. Everywhere, people are ignoring those in their physical vicinity so they can hold court with acquaintances farther away.

Blurring the lines between life and inanimate matter, biologists announced Friday that they'd created six different chemical alternatives to DNA and coaxed them to undergo evolution. A description of these code-carrying molecules, called XNAs, was published in the journal Science. The work bolsters a prevailing hypothesis that life as we know it evolved from simpler life forms, no longer here, and those evolved from something simpler. There may be no moment when the first life emerged, but instead an evolutionary process by which chemicals that most of us would consider non-life gradually gave rise to living cells through natural selection.

Cheney released with new heart WASHINGTON - Former Vice President Dick Cheney was released from the hospital Tuesday, 10 days after getting a new heart, his office said. Cheney, 71, received the organ March 24 from an unknown donor at Inova Fairfax Hospital in Falls Church, Va. "As he leaves the hospital, the former vice president and his family want to again express their deep gratitude to the donor and the donor's family for this remarkable gift," aide Kara Ahern said in a statement.

It was the time of P.T. Barnum, when people would line up to see a whitewashed elephant or a carefully faked petrified giant. But in 1868, a display in Philadelphia proved that reality could be far stranger than fiction. That year, the Academy of Natural Sciences showed the world its first glimpse of a real dinosaur skeleton - a 15-foot-tall Godzilla pulled from a pit in Haddonfield. The creature threatened to obliterate the traditional picture of the universe. Along with Darwin's theory and a revolution in geology, dinosaur fossils were opening the human imagination to lost worlds on our own planet, separated by vast epochs of time.

When Rush Limbaugh called law student Sandra Fluke a "slut" and a "prostitute" last week, it caused an uproar and raised a scientific question - why is it so hard to imagine using the same word to insult a man? The epithet slut can be devastating to a woman's reputation in our society, but a man's reputation might even be enhanced by having many sexual partners. He might be called "a player" instead. This bit of sexual inequality is observed in diverse cultures, said Todd Shackelford, an evolutionary psychologist at Oakland University in Michigan.

Election seasons can serve as a reminder of just how deeply mysterious the human mind remains. Particularly puzzling is the fact that people are heavily influenced by political advertising on television. Our rational sides tell us that these ads are unlikely to serve as unbiased sources of information. And yet, in states where the bulk of negative ads focused on Mitt Romney's rivals, Romney won. In states where Rick Santorum or Newt Gingrich ran the most negative ads, they surged.

The Barnes Foundation, whose renowned collection of early modernist art will open in May on the Benjamin Franklin Parkway after moving from Merion, plans to install a soaring sculpture by contemporary master Ellsworth Kelly near the entrance to its new building. The Barnes Totem , a slender, stepped blade rising 40 feet into the air, is a gift from the Neubauer Family Foundation, Barnes officials said. Joseph Neubauer, vice chair of the Barnes board of trustees, characterized the bead-blasted stainless-steel work as a gift for the city, a welcoming statement to gallery visitors and passersby alike.

Timing is everything, and if there was ever a scientist whose legacy was tarnished by bad timing, it was Jean Baptiste Lamarck. The French naturalist lived from 1744 to 1829 - and published his own evolutionary theory decades before Darwin's theory went public in 1859. In the popular imagination, those who've heard of Lamarck tend to associate him with a wrongheaded version of evolution in which giraffes can grant their offspring longer necks by reaching for high leaves. Historians say this unfair portrayal was engineered by Lamarck's enemies.

We humans can be a cocky species - so much so that a realistic self-image can be seen as a symptom of trouble. Take the reaction to a recent survey in which about 52 percent of college students rated their emotional health as below average. About half of them are, after all, going to be below average. But the UCLA researchers who did the survey say it indicates a deeper problem. In past surveys, at least 64 percent of the respondents said they were above average. What's going on here?