Masting is what biologists call the pattern of trees for miles around synchronizing to all produce lots of seeds – or very few. Why and how do they get on schedule?

... and it's poised to find thousands more. But will we find another Earth?

As temperatures drop, broad-leafed deciduous trees – think maples and oaks – withdraw the green chlorophyll from their leaves. Their leaves turn colors and fall. Evergreens solve the problem of winter in a different way.

This is the weekend we "fall back" here in the U.S. Are you glad? Sad? Mad? Advocates say daylight time saves energy and wins wars. Studies show injuries and illnesses rise when clocks change.

What kicked off a rapid cooling on Earth 12,800 years ago? Some geologists believe a fragmented comet or asteroid collided with Earth and caused the change. Read more from a scientist whose fieldwork at a South Carolina lake adds to the growing pile of evidence.

New research suggests that the tiny human species - that survived until about 18,000 years ago, later than any human species other than our own - evolved its small size remarkably quickly while living on an isolated island.

On average the ocean is 2.3 miles (3.7 km) deep, but many parts are much shallower or deeper. In the deepest zones, life forms have adapted to live in the dark, under crushing water pressure.

The stars are accessible to everyone, but where can you get the most from the night sky? Here are 10 great dark-sky places - mostly in the U.S. but also in Australia, New Zealand and Chile - for skywatching and stargazing.

Maps of the long filaments of gas that hold the universe together might one day help trace and unveil dark matter.

Air temperatures in the Arctic are increasing at least twice as fast as the global average due to climate change. What worries climate scientists about this?