Environment9271 articles archived since 1845

Chlorofluorocarbons (CFCs) are heavier than air, so how do scientists suppose that these chemicals reach the altitude of the ozone layer to adversely affect it?

Most unbred animals (English sparrows, for example) all look alike to me. People, of course, not so. Do I just not recognize the traits that distinguish one animal from another, or do they really lack the individual distinctiveness of humans?

Why do regular, wavelike shapes form when the wind blows over the sand on the beach for a long time? And what determines the spacing (frequency) of these waves?

What do we know about the origin of the earth's oceans? Is it more likely that they derive from icy comets that struck the young earth or from material released from the earth's interior during volcanic activity?

How Did the "Smile" Become a Friendly Gesture in Humans?

In almost all other species, especially primates, baring one's teeth is a threat or a show of potential force. Are there any cultures in which smiling is not considered friendly?

What kind of illnesses do insects get? Do we have the medical knowledge to cure an insect if we knew it was sick?

Why are rainbows curved? Is it because of refraction in the drops of water?

Why are impact craters always round? Most incoming objects must strike at some angle from vertical, so why don't the majority of impact sites have elongated, teardrop shapes?

How do flies and other insects walk up walls, ceilings and even apparently smooth glass windows? It seems unlikely that they have adhesive feet--so how do they do it?

What kind of evidence could be found in the fossil record (or anywhere else) that would prove whether or not some dinosaurs were warm-blooded?

What is the current status of the 'invasion' of non-native zebra mussels in the Great Lakes? Has the invasion been stopped or controlled? And what ecological damage has this creature caused other than the clogging of drainage pipes?

How close are we to being able to reconstruct the DNA of long-extinct creatures--dinosaurs, for instance? What kinds of technical hurdles do we need to overcome, and do the recent advances in cloning bring us any nearer to the goal?

Why does the ocean appear blue? Isit because it reflects the color of the sky?

I lived a long time in the tropics and often heard of, but never saw, the "green flash" that is said to occur just at sundown. Does it actually exist, and if so, what causes it?

IN THE DRINK

Cities try cooling off with deep lake water

DESERTING THE SAHARA

Dying plants harvest harsh surprises from climate change

PIRATE FEAR

Controversy heats up about chlorfenapyr, a.k.a. Pirate--a pesticide some claim is the next DDT

Why do we have a hurricane season?

CONGO CITY

Gorillas and the rain forest come to the Bronx

STRIKE ZONE

A little ecology and technology could keep birds away from airplanes