Evolution

Just as antibiotics have bred resistance in bacteria, vaccines can potentially lose their effectiveness over diseases they controlled. Researchers are working to head off the evolution of new threats.

For the first time, researchers have traced the genetic programs that guide the development of each cell in early embryos. Surprisingly, even cells that start out different can end up the same.

To date the branches on the evolutionary tree of life, researchers are looking at horizontal gene transfers among ancient microorganisms, which once seemed only to muddle the record.

How the ultra-cooperative behavior of ants, bees and other social insects could have evolved continues to challenge formal analysis. But a new theory about hedging bets against nature’s unpredictability may change the math and shift the debate.

For decades, researchers have commonly assumed that higher oxygen levels led to the sudden diversification of animal life 540 million years ago. But one iconoclast argues the opposite: that new animal behaviors raised oxygen levels and remade the environment.

An unlikely team offers a controversial hypothesis about what enabled animal life to get more complex during the Cambrian explosion.

A newfound pair of giant viruses have massive genomes and the most complete resources for building proteins ever seen in the viral world. They have refreshed the debate about the origins of these cellular parasites.

Modelers find evidence that a combination of competition, predation and evolution will push ecosystems toward species diversity anywhere in the universe.

The neuroscientist Erich Jarvis found that songbirds' vocal skills and humans' spoken language are both rooted in neural pathways for controlling learned movements.