Whereas the use of synthetic fertilizers has greatly expanded agricultural productivity in many parts of the world, an increase in their use can create serious environmental problems such as water pollution, and their substitution for more traditional fertilizers may accelerate soil structure deterioration and soil erosion.

According to two teams of paleontologists, recent fossil discoveries in Pakistan show that whales, porpoises, and dolphins are more closely related to some of the oldest known even-toed ungulates--a group of hoofed mammals that today includes cows, camels, pigs, and hippos--than to any other mammals.

Surveys have shown that in up to 40 percent of elderly people living independently in affluent countries, the consumption of one or more essential nutrients is insufficient or they have deficient levels of these nutrients in their blood.

When the temperature of a gas is increased, it is either accompanied by an increase in pressure if the gas is enclosed in a container, or an increase in volume if the gas is able to expand.

Like any star of similar mass would do, once the Sun has exhausted the hydrogen in its core, it expands into a red giant, eventually ejecting its outer envelope of gases to become a white dwarf.

Due to automobile-related jobs in the 1920's employing one of every eight workers, the automobile industry dominated the American economy.

It was only after Katharine Graham became publisher of The Washington Post in 1963 that it moved into the first rank of American newspapers, and it was under her command that the paper won high praise for its unrelenting reporting of the Watergate scandal.

The population of India has been steadily increasing for decades, and it will probably have what is estimated as 1.6 billion people by 2050 and surpass China as the world's most populous nation.

India, like Italy and China, has no single dominant cuisine: Indian food comprises many different styles of cooking, with each a product of their regional influences, from the fiery vegetarian dishes of the south to the Portuguese-influenced Goan cooking of the west, to the more familiar Mogul food of the north.

Many population studies have linked a high-salt diet to high rates of hypertension and shown that in societies where they consume little salt, their blood pressure typically does not rise with age.