When I am surfing the Web, I want to be drawn by articles on Europe’s political history, but I end up reading menus from Alcatraz prison. Why does that happen?

Curiosity seems beyond your control, and trying to direct it sounds like forcing yourself to find a joke funny. But if you know what boosts curiosity, you may be able to understand it a little better.

During the evolution, curious animals were more likely to survive because they learned about their environments. Humans, too, will give up a known payoff to investigate the unknown. Scientists did some experiments. In the first experiment, subjects were asked to choose one of four photos, each carrying some chance of a cash prize. Photos repeated, so subjects learned to pick the best. But when a new photo appeared, they chose it more often than the familiar ones. This preference for new one is, of course, the reason why producers regularly change product packaging.

Also, curiosity improves learning. In the second experiment, subjects read simple questions and rated how curious each made them feel. Later, they saw the question again, each followed by a photo of a face, and judged whether that person looked as if he or she would know the answer. In a surprise final memory test for the faces, subjects better remembered those appearing after the questions that make them curious.

This function of curiosity—to heighten memory—is the key to understanding why we’re curious about some things instead of others. We feel most curious when exploration produces the most learning. Suppose I ask you, “what’s the most common type of star in the Milky Way?” You’ll obviously feel uninterested if you already know the answer. But you’ll also feel little curious if you know nothing about stars; if you learned the answer, you couldn’t connect it to other knowledge, so it would seem nearly meaningless. We’re maximally curious when we sense that the environment offers new information in the right part to complement what we already know.

A new unnamed species of crocodile (鳄鱼) indigenous to Australia has been found in the middle of the outback. The species of crocodile presently on extinction, belonging to the Baru crocodile, is new to experts despite the fact that the animal wandered around the Australian continent 25 million years ago.

Adam Yates, senior leader of earth sciences, said that Australia’s suitable instance of the crocodile’s bone was discovered in 2009 at the site of Alcoota Fossil which is eight million years old and is 200 kilometers north-east of Alice Springs, Australia. Dr. Yates revealed that other specimens (样本) had been discovered before. He said, “This specific specimen is one of the last of its kind. It is the nicest and the bone of the Baru crocodile is the most complete among all that have ever been discovered so far.” Thanks to the bone’s condition, Dr. Yates said that it would turn into the name-bearing specimen or what he referred to as “the holotype (正模标本)” of the new species.

Dr. Yates revealed that the modern Australian crocodile is known for being ancient and fixed, but that is not really true. “The current Australian crocodiles are truly new arrivals on the Australian continent. They are part of the genus Crocodylus, which likely has its origins in Africa,” he said. “This species of crocodile immigrated and conquered Australia just a few million years ago. However, Australia’s main native crocodiles, like this one, have totally gone extinct,” he continued.

Dr. Yates also revealed that the size of this Baru crocodile can be compared to a recent saltwater crocodile; however, due to the fact that the bone is strong, it would have had more weight. He said it is likely that it weighed more than a saltwater crocodile of an equal length. So they are looking towards many hundreds of kilos. Studying the details of the bone will bring hints not only to the altering state of Australia’s environment from ancient times till now, but also to how this specific crocodile varies from other species that are known.

He also said they have to get down to the details of its structure and make a demonstration on why the structure of this one is sort of different from all the other species of ancient crocodile from Australia that are known.

Dr. Yates said the size of the bone shows that the animal was very powerful. “Its actually powerfully built heavy, thick, deep jaws, and really large teeth all imply that this was a crocodile that specifically takes megafauna (巨型动物),” he said. He added that modern crocodiles mostly survive on small prey and small fish. This guy didn’t survive on small things. Dr. Yates said modern saltwater crocodiles also had the ability of taking larger animals.

The sharp fin (鳍). The rows upon rows of sharp teeth. The large black eyes. The sharks you see on television in Jaws or Discovery’s ”Shark Week“ are not the friendliest looking creatures. They aren’t exactly an animal you want to find near you while swimming in the ocean. Despite their portrayals (刻画) in movies and popular culture, sharks are complicated, misunderstood creatures that are weaker than they appear.

One very common misunderstanding about sharks is their desire to hunt humans. Actually when sharks attack humans, it is because they mistake a human for their normal prey (猎物),seals or dolphins. They don’t seek out humans on purpose. Statistically, you are more likely to be struck by lightning than be bitten by a shark.

Sharks are very important to the ocean as they are at the top of the food chain. Some sharks even control the balance of an ecosystem through fear alone. Tiger sharks in Australia help protect seagrass meadows from turtles. Turtles eat the seagrass and without the sharks, will destroy these meadows. When tiger sharks are present though, the turtles are scared away, holding back their appetite for seagrass and protecting its growth.

Though sharks have a reputation for being very scary to humans, the sad truth is that they should be scared of humans. The number of sharks in the ocean is steadily dropping. There are a few reasons for this. For one, they mature quite slowly, over several years, and produce relatively few young. For another, overfishing of sharks is happening because more and more people want their fins. About 100 million sharks are killed every year according to National Geographic. Shark fin is a way for people to show off their wealth. Shark fins are also believed to have medicinal benefits, though there is no evidence or proof that they actually do.