When you go swimming, you are always told to be careful not to bruise yourself against the rocks. However, fish swimming in the water rarely get bruised moving through cracks in rocks and the branches of thorny water plants. It's because they have scales on their bodies which serve as a protective layer. The toughness of these scales is determined by how harsh the environment is. For example, the scales of fish living in water where they must protect themselves from ragged surfaces are tough. Some people even use them as a substitute for sandpaper. On the other hand, fish that do not encounter many rough surfaces have very soft scales.

Butter is made from milk, and milk spoils very quickly, but butter doesn't. Why not? In water and microbes lies the answer. Food-spoiling microbes (bacteria, yeast, and mold) love water; the more water the better. Milk is about 94 percent water, which is great for bacteria, yeast, and mold. If you leave a container of milk in a warm room, it takes only a few hours before the milk goes bad. Butter, on the other hand, will still be edible for a few days ― and sometimes for up to a few weeks. That's because butter is only about 30 percent water. Also, most butter is salted, and salt kills many microbes.

The Negro Motorist Green Book, or simply the Green Book was a guidebook for African American travelers that provided a list of hotels, bars, restaurants, gas stations and other establishments throughout the country. Victor H. Green published it annually from 1936 to 1966 when discrimination against African Americans was widespread. During this period, African Americans faced racial prejudice, refusal of food and lodging, and physical violence while traveling around the United States. The Green Book featured African American-friendly services and places, and its coverage spread to include not just the New York area, but much of North America. The information included in the Green Book was able to help increase their safety and treatment.

As humans spread out across the world and use more and more land, we leave other species little space to live on. According to a study by Yale ecologists, by 2070, increased land use by humans is expected to put 1,700 species of amphibians, birds, and mammals at great risk of extinction. In particular, species living in South America, Central and East Africa, and Southeast Asia are going to suffer the greatest habitat loss and increased extinction risk. Walter Jetz, the professor of ecology and evolutionary biology at Yale, caution that this problem affects not just the countries where the species live, but the whole world. Losses in species populations can permanently damage the functioning of ecosystems and human quality of life, said Jetz. While biodiversity destruction in far-away parts of the planet doesn't seem to affect us directly, its consequences for human livelihood can spread globally.

To admire a person's ability and praise them for what seems like an innate talent is tempting to us all. If your kid does well on a test, you might say, You're so brilliant! If your friend plays a great soccer game, you might say, You're so athletic! However, research on the psychology of success by Carol Dweck suggests a better strategy. Praising people for their natural ability often causes harmful effects. Once people start to think that skills and talents are things they either have or don't have, what happens when they fail at something? They'll get frustrated and think they're not so great after all. Instead, though, what if you praised people for their effort? What if you told your kid, for example, you tried so hard for the test or your friend, you really put in effort in the game today? Studies show that focusing on the effort and determination that people put in makes them better at overcoming future difficulties.

We often use food not just as a means to satisfy our physical hunger, but also for comfort, stress relief, and to reward ourselves. And when we do, we tend to reach for unhealthy foods from our kitchen which contain high amounts of saturated fat and refined sugar. You might reach for a piece of chocolate cake when you're feeling depressed or order a pizza if you're stressed or lonely. Using food to satisfy your emotional needs is called emotional eating. Unfortunately, emotional eating doesn't fix emotional problems. In fact, it usually makes you feel worse. Afterward, not only does the original emotional issue remain, but you also feel guilty for overeating. Emotions usually don't last long, so you only need to distract yourself from eating for a short time, until the emotion passes. Try going for a short walk or turning to an activity you enjoy.

Toward the end of the 19th century, people were looking for faster and more efficient ways to fasten several sheets of paper together. Sewing stacks of pages together with needle and thread, for instance, was difficult and time-consuming. Then, in 1879, an American company began manufacturing the McGill Single-Stroke Staple Press. This tool was so simple and effective that people have used tools like it since then. It works when you place pieces of paper under its arm and press down firmly; this releases a staple, drives the staple's sharp ends through the paper, and bends the ends together against the underside of the paper. Today, it's used in offices, schools, and homes worldwide. It's called a stapler.

Hot and cold are the two main words that we used to describe how we perceive temperature. They are imprinted on our consciousness at a very early age. And for the most part, we have no problem telling the difference between the two. Yet in a few cases the difference between them isn't altogether clear. Here's an example: If you were blindfolded and someone touched you first with a hot iron and then with a piece of dry ice, you probably wouldn't (C) be able to tell hot from cold. This is a simple demonstration of a key fact. Physiological, or bodily, sense isn't a dependable method for measuring temperature.

Electric cars have many advantages compared to traditional ones. They do not cause air pollution and global warming by emitting carbon dioxide. They also produce only a little noise pollution because they run quietly on battery power. However, despite these benefits, safety issues have been raised about these green vehicles. For example, it is difficult to hear electric cars coming. So they could be dangerous to some pedestrians, especially the blind, who rely on their hearing to cross roads. In response to this concern, groups of scholars, blind people, and police insist that a sound-making function be introduced in these eco-friendly vehicles.

Brands today frequently encounter changes that affect the way that consumers interact with them. In the past, when consumers wanted to give feedback, they would write or call. Today, consumers can interact with brands via social networks in a far more immediate way. Several years ago, the US clothing chain GAP tried to change its logo. For decades, the logo had been white lettering on a blue square, with a classic feel. But as soon as they offered a more modern looking logo, they realized that they shouldn't have tried it. Consumers missed the old version. They took Facebook and Twitter to express their disappointment, and even anger. A week later, GAP released a statement, saying that they would revert to their classic logo.

When I got an email last March from a restaurant app notifying me that my order was on its way to an address 3,000 miles away from my location, I thought it was not that big of a deal. I informed my bank of the wrong charge and got a refund. However, that was just the beginning. I should have taken that more seriously. Five days ago, I found that $9,000 had been transferred away from my account two days previously without my knowledge. I called the bank immediately. They blocked any access to my account for investigation, including mine. Since then, I have been borrowing money from my friends to cover my expenses! Now that my account has been hacked twice, I'm afraid that this bank must have a weak security system.

An 18,000-year-old puppy buried for centuries in frozen mud was discovered in a layer of permafrost in Siberia's Far Eastern reaches. The fur, skeleton, teeth, head, eyelashes and whiskers of the puppy are still present. Scientists say that it must have frozen quickly. before other animals could get to it. But scientists don't know whether it is a dog or wolf, and it was said more DNA research would be conducted in the coming months. Many scientists say dogs evolved about 15,000 years ago from a species of extinct wolves. Others insist that it could have happened much earlier. After thousands of years of being domesticated by humans, these wolves evolved to become our modern-day companies. Scientists think this puppy may help illustrate the connection between dogs and wolves.

One of the worst things about growing old is the feeling that you are becoming invisible. Shop assistants, waiters, and other customer-service workers tend to overlook old people, and not many movies or TV shows include characters who are very old. Perhaps the worst thing about being old is not being listened to; people tend to treat the aged as if they have nothing interesting or valuable to say. With so few people taking any notice of them it's no wonder that some old people bore kids nearly to death whenever they get the chance to talk to them. In a youth-obsessed society, you need a lot of strength and good humor to endure the negative aspects of aging.

As you know, I have been satisfied with your medical service for the past six years. You are always so kind to me and so professional. However, are you aware that the condition of your waiting room is very disappointing? The carpet is rarely vacuumed, the plastic plants are thick with dust, and the magazines and children's playthings are disorganized. A clean environment seems particularly important in a clinic and although I know what an excellent physician you are, I can't help worrying about how clean everything else is. I hope you find this letter helpful rather than unpleasant—it was written with the best of intentions.

Before picking out a souvenir to take home, consider how it was made and where it came from. If animal products such as bones or skin were used to make it, just leave it on the shelf. For example, a tropical island gift shop may sell beautiful tortoiseshell items such as jewelry. But people who buy and sell tortoiseshell products have caused terrible damage to rare and threatened populations of turtles. Taking souvenirs directly from nature is another bad idea. That's because many countries protect natural things, including seashells and even some kinds of rocks. Instead, choose something that's good for the place you visit, such as paintings or crafts produced locally.

Is there such a thing as a sixth sense? Or only the five scientifically proven senses of sight, hearing, smell, touch, and taste? The imagined sixth sense is the near-magical ability to perceive things that can't be perceived using the known human senses. Imagine, for example, that you decide not to get on an amusement park ride because you have a sudden feeling that something bad will happen Then imagine that the ride crashes, seriously injuring a lot of people. You might be tempted to believe that your sixth sense stopped you from getting on the ride, but it's more likely that your bad feeling and the crash were simply a coincidence.

On January 12, 2020, the Taal Volcano in the Philippines woke after 43 years of quiet and began to emit gases, ash, and lava into the air. In the following weeks, the eruption dropped a layer of unusually wet and heavy ash on the surrounding area, and caused most of the vegetation to wither. The damage affected more than just plants. A large number of people died while the volcano erupted. A lot of livestock and companion animals were left behind when the local population evacuated. Ash even affected the fish raised in Taal Lake. About 30 percent of the fish cages in the lake were destroyed during the eruption. The landscape of the area was damaged by ash, still looking more like the moon than the tropical regions even after two months.