As many as 10 of the 17 kinds of penguins(企鹅)may be in danger of disappearing.The number of penguins have decreased by 30% since 1987.

Penguins are black and white birds that live in the southern part of the world.They are common in South America，New Zealand，Australia and South Africa.Many live near cold waters.But some live near warm waters in Galapagos Islands.Penguins cannot fly，but they are fine swimmers.Penguins eat fish and krill(磷虾)．

The warming of the earth is the reason for the decrease in the number of penguins.The heating of the air has caused ocean waters to become warmer.Higher water temperatures have reduced the supply of fish and krill.Some years later these birds are completely unable to reproduce(繁殖)．Besides，many adult penguins die of hunger.

Widespread(广泛的) fishing，exploration for oil and oil leaks(漏) also make penguins be in danger.Poisonous things in ocean waters are another danger.Penguins also have their enemies，including wild dogs，sharks，seals and sea lions.

News about penguins is not all bad，however.Several years ago，oil leaking from a ship hurt 40% of the penguins in South Africa.The penguins became covered with oil.But thousands of people helped clean and treat the birds well.Then they returned the penguins to the wild.Now these South African penguins are reproducing in higher numbers than before the oil leaking.

Penguins are the number-one attraction for many visitors to Antarctica. If you go on a ship that is allowed to make shore landings, you may see them. But to get a close look at penguins, you have to be smart.

First of all, keep in mind that Antarctica’s visitor rules require that you remain at least five meters away from the penguins in order not to disturb them. You could easily become responsible for the death of a little penguin or the destruction of an egg if your too-close presence should disturb a penguin parent.

If a penguin is trying to move away from you, you must stop what you’re doing and back off even if you’re farther than five meters away. However, the rules don’t prevent a curious penguin from approaching within five meters of you — as long as the bird makes the move, not you.

Little penguins, in particular, are quite curious. I’ve seen several lucky tourists who were astonished to find that little penguins came right up to them. If a penguin comes extremely close to you, remember that you are not allowed to touch or hold it.

Here are more tips for getting close to penguins.

Ignore the smell: where penguins live is filled with guano（海鸟粪）and the smell takes some getting used to.

Be quiet because loud noises make penguins nervous. Fast or sudden movements signal meat — eating animals to penguins, and they react accordingly, so slow down when you walk around them.

Since it may take half an hour or more before the penguins get used to you, you need to be patient. Put away your camera — too often people are so focused on getting the pictures that they forget to look with their own eyes, but most of your most memorable experiences in Antarctica will be marked in your mind, not on a roll of films.

Bees may soon need to add protein shakes to their diet. Pollen (花粉) normally provides their protein (蛋白质). But rising levels of carbon dioxide (CO₂) in the air have reduced the protein in pollen. That’s what a new study finds.

Scientists compared recently collected flowers from Canada goldenrod. Then they compared pollen in them to pollen in goldenrod reserved at a museum in Washington, DC. They found today's plants have less protein. Protein levels in pollen from the older flowers were 18 percent. Today's goldenrod pollen has only about 12 percent protein. That's about one-third less than 172 years ago. Over that same period, CO₂ levels have gone up by more than one-third. Back more than 170 years ago, they were about 280 parts per million in air. Today they are about 398 ppm.

To test whether CO₂ changes had played a role in the falling protein levels, the researchers did some tests. They grew goldenrod for two years at CO₂ levels of up to 500 ppm. More CO₂ in the air led to lower levels of protein in the flowers’ pollen.

Joan Edwards, one of the researchers, says that this drop in pollen protein could affect a bee’s diet and health. It would be like eating junk food, tasting good but offering less nutrition (营养).

Honeybees need to eat lots of protein. They use it to feed their young. They also need it to keep their immune systems healthy, says Cédric Alaux, a bee biologist at the French agricultural research agency.

Bee populations have been decreasing worldwide in recent years. A drop in their food quality might play a role, Edwards says. And that drop might affect crops too. “The health of the bee population is not just for the flowers and the bees and biodiversity.” She worries it also could play a role in “human health and well-being.”