4 . We know that our pet dogs and cats can recognize our faces, but our pet fish? A team of scientists from the UK and Australia have discovered that archerfish (喷水鱼) can distinguish human faces!

This marks the first time that a species of fish has shown such an ability. Such abilities have been previously shown in birds, but unlike fish, they have been proven to possess structures similar to the neocortex (大脑新皮层), the researchers added.

“Being able to distinguish between a large number of human faces is a surprisingly difficult task,” Dr. Newport said, “mainly due to the fact that all human faces share the same basic features.”

During their experiments, Dr. Newport and her colleagues presented archerfish with two images of human faces, and trained them to choose one by spitting jets (喷射流) of water at that picture. Next, the fish were presented with the familiar face and several that were unfamiliar, and were able to correctly pick the one that they had been trained to recognize, even when features such as head shape and color were removed from the selected pictures.

In the first experiment, the archerfish were tasked with picking the previously learned face from a group of 44 new ones, which they did with 81 percent accuracy. In the second, the researchers decided to make things a little harder. They took the pictures and made them black and white and evened out (使平均) the head shapes. You would think that would throw the fish for a loop. But no, they were able to pick the familiar face even then-and with more accuracy: 86%!

“Fish have a simpler brain than humans and entirely lack the section of the brain that humans use for recognizing faces. Despite this, fish may still be capable of finding the face they are trained to recognize,” Dr. Newport said, “The fact that archerfish can learn this task suggests that complicated brains are not necessarily needed to recognize human faces.”

5 . Beer and eggs are commonly seen in the kitchen. However, scientists recently found that they were used in historic paintings, too.

To preserve Danish paintings, a group of researchers studied what was the composition of ancient paint or what it was made of. They did experiments on small pieces of paintings that had already been cut off from the original artwork.

According to their paper published in Science-Advances, grains and yeast (酵母) were found on the base of the paintings. Beer was the most common drink in the 19th century in Denmark, and its by-products were spent (用过已废的) grains and yeast.

The study showed that they were used to provide a stable painting surface. Researchers also pointed out that beer by-product was used as a “glue” because it had a lot of sugar. With beer added, the paint can also dry faster.

Apart from beer, egg has long been found in oil-based paints used by artists in the 15th century, such as Italian painter Leonardo da Vinci. A recent study published in Nature Communications may have “cracked” the secret of how eggs can help preserve artworks.

The researchers re-created the ancient paint by adding egg yolks (蛋黄) to oil paint. They then looked into how it changed over time. The findings showed that the proteins in the yolk helped to slow down the oxidation (氧化) of the paint and reduce wrinkling (皱褶) as the egg makes the paint more smooth.

However, the oil paint with added egg usually takes longer to dry. It seemed fine for artists. They were willing to accept that their work would be preserved for a longer period.

The more we understand how artists choose and use their materials, the more we can “appreciate what they’re doing”, Ken Sutherland, an expert at the Art Institute of Chicago, US, told Science News. Sutherland added that research like this could help people have a deeper understanding of the artworks.

7 . Experts recently suggested that teens should start having early bedtimes. Before you think it as a habit suited only for young kids, consider that there are serious advantages in being well-rested. And now, even more research suggests that putting phones away before going to sleep is important to teens’ well-being.

A new study from Seton Hall University School of Health and Medicine Science found that 62 percent of kids used their smart phones before bed, and it’s causing less sleep and poor performance in school.

Those teens who text before bedtime tend to go to sleep later, and get up later in the morning. Such behavior can be associated with mental health illnesses like depression or anxiety. Besides, once teens do receive a text, experts found, they tend to respond right away. Then the text conversation continues — leading to an even later bedtime.

The study’s co-author Dr. Peter Polos says this leads to excessive stimulation (过度刺激) at night. Light from electronic devices can prevent the secretion (分泌) of melatonin — a hormone (荷尔蒙) that promotes sleep, which makes sleep difficult in the face of overuse of smart phones at night. It’s true! More screen time means less sleep time; other studies have suggested the same idea.

As for a final piece of advice, Dr. SushanthBhat says, since getting the proper amount of sleep is very important for brain development and learning in the teenage years, our study should encourage parents and guardians (监护人) to limit the smart phone usage of kids at night. Keep in mind that teens aren’t the only ones addicted to their phones! Adults can also benefit from setting a tech curfew (宵禁) for themselves. After all, kids learn by example!

8 . The minutes leading up to a vacation are often an exciting time. As people check their homes and pack the last items into their suitcases, they often dream about the fun times that lie ahead. In Russia, however, there is one final step that people take to ensure a good trip. Before they walk out the door, Russians take a brief pause and silently sit on their suitcases for a few moments.

“Sidet’na chemodanakh” or “sitting on suitcases” is an ancient custom that will be a familiar ritual to anyone who grew up in Russia, or any migrant family that obeyed motherland customs. This unusual ritual started hundreds of years ago. In the years before Christianity, Russians believed that good and evil spirits lived inside their homes. They thought that the key to living a good life was to keep these spirits happy at all costs. If a person rushed out of his or her home before a trip, there was a good chance they would forget something. When that person returned a few minutes later to get it, they would disturb the evil spirits in the home. In response, the spirits might follow them out the door and accompany them on their trip. Since the spirits were offended by the person, they would bring them bad luck and possibly cause them harm.

Although many years have passed since suitcase sitting began, the practice continues to this day. As the Soviet Empire grew during the Cold War, suitcase sitting even spread throughout Eastern Europe. Although it is rooted in superstition (迷信), suitcase sitting is actually quite practical. It can prevent people from forgetting passports, plane tickets, or other items that are needed during trip. In addition, it also provides a brief moment of relaxation that can help get a journey started on the right foot. Besides that, if someone has packed too many clothes, suitcase sitting can help get it zipped up.

9 . There was a time when the word “surgery” used to scare people, and they would try their best to avoid a surgical procedure. The feeling is understandable, as the idea of a large cut on your body is discomforting in many ways. However, thanks to the advances in medical science, surgical techniques have improved considerably.

Compared with the traditional open surgery, minimally invasive surgery (微创手术)has several benefits to offer. Not only is the procedure quick and less painful, but also ensures rapid recovery. Now, surgical procedures, either big or small, are done within a few minutes to a few hours. The best part about the minimally invasive surgery is the painless procedure. The advanced techniques are helping with quality treatments to patients who have to undergo (进行) surgical procedures.

Unlike the traditional open surgery that requires a large cut, a surgeon makes multiple tiny cuts of less than an inch. For the process, the surgeon uses small surgical instruments, such as a tiny tube with a mini camera at one end. Once the surgeon marks the cuts, he then passes the tiny tube through one of the cuts. The doctor monitors the images taken by the mini camera on the screen and uses them as a reference. These images give the surgeon a clear picture of the area undergoing the surgery. After the surgery, the surgeon cleans the cuts and sometimes places a bandage for additional support.

Minimally invasive surgery has become the first choice of patients with multiple medical conditions. In fact, it would not be wrong to say that these surgeries are now the standard surgical procedures for many routine operations. Whether you have a minor issue or want a surgical intervention for a major health condition, it is the best option.