Only a few decades ago, Baja California was mostly unknown to the outside world, sparsely populated, and difficult to visit. And most of it is very dry desert. But crowds and developers have discovered the southern part of the peninsula and have arrived in droves, threatening the very features that make the Peninsula such an unusual place. Meanwhile, overharvesting in the Gulf of California has caused fish stocks to plummet and threatened the entire ecosystem. Now, Mexicans and international experts are fighting back.

Carnival or Mardi Gras is a time of parades and exuberant partying just before the forty days of Lent, when many Christians must adopt of more austere way of life. Latin America features hundreds of variations on the festivities. Mexico has two sensational parades like no others, in towns that are otherwise obscure--Huejotzingo in the state of Puebla and Tlacayapan in the state of Morelos. These two parties are as different as any two celebrations can be.

Potters in northwest Mexico have been producing fine ceramics for more than a thousand years. Excavations at Paquime, Chihuahua reveal a culture renowned for its designs-and exports-500 years before Europeans arrived. Sixty years ago, villagers not far away discovered that they, too could produce fine ceramics. Today their products are world-famous.

The abundance of reptiles, especially snakes, in the Amazonian jungle is hardly surprising. Native cultures, far from fearing snakes, view them as spiritually significant elements of nature. From the gigantic anaconda to tiny tree vipers, snakes are part of life-and religion--in Brazil's Amazon.

Brazil is larger than the contiguous United States, and it is mostly tropical. It is not surprising that it is home to a host of venomous critters, mostly scorpions, spiders, and snakes. Each year many tens of thousands of Brazilians are stung or bitten and require treatment. Many of them and many thousands of victims in other countries as well, owe their lives to antivenin produced by the Butantan Institute in Sao Paulo. It's home to hundreds of thousands of venomous creatures, all contributing to the protection of human lives.

Arizona is not known for its active volcanoes, but its landscape is dominated by the products of millions of years of volcanic explosions. And the plumbing that funnels molten lava to the surface is still intact and waiting for the opportunity to erupt. The last explosion occurred around the time Normans were invading England. It could recur at any time. More ancient activity tore up the landscape and left behind a heritage of destruction and creation.