Scientific American Magazine

The American West once harbored multiple communities of dinosaurs simultaneously—a revelation that has scientists scrambling to understand how the land could have supported so many behemoths

Some say its glory days are long gone, but the universe has life in it yet. Brand-new types of celestial phenomena will unfold over the coming billions and trillions of years

Governments and corporations have more control over the Internet than ever. Now digital activists want to build an alternative network that can never be blocked, filtered or shut down

Scientists have rid one man of HIV by preventing the virus from entering certain immune cells. But the treatment was dangerous and likely unrepeatable. Can they figure out a safer, more broadly achievable way to help millions more?

If renewable energy is going to take off, we need good ways of storing it for the times when the sun isn't shining and the wind isn't blowing

Existing antidepressants leave a lot to be desired. They can take weeks to start working, and they fail many people. Researchers are scouting for better options

How can identical twins grow up with different personalities? "Jumping genes" move around in neurons and alter the way they work

Michael E. Mann set out looking for a big scientific problem and wound up at the center of a political storm over climate change. Now he tells his side of the story