Have you ever wondered when dogs first became “man's best friend” and the world's favourite pet? If you have then you're not alone. When and where dogs first began living side-side with humans are questions that have stirred hot debate among scientists. There are a few hard facts that all agree on. These include that dogs were once wolves and they were the first animal to be domesticated(驯养) by humans. They came into lives some 15000 years ago, before the dawn of agriculture.

    Beyond that, there is little agreement. The earliest bones found that are unquestionable dogs and not wolves date from 14,000 years ago. However, 30,000-year-old skulls have been discovered in France and Belgium that are not pure wolf and some scientists think could be dogs.

    With such puzzling evidence, many scientists are now turning to DNA to find out when and where dogs were first domesticated. In one research project, tens of thousands of blood samples have been taken from street dogs around the world. The plan is to compare them with those of wolves. It's even possible to analyse DNA from ancient bones. Tiny pieces of the 30,000-year-old skulls mentioned earlier are currently being studied, and another DNA study has already shown that ancient dogs preserved in the Alaskan ice-fields evolved from Asian wolves, not American ones.

    Indeed, the ancient DNA may turn out to be more informative than the DNA of living dogs. Because dogs have accompanied humans around the world for thousands of years, their current distribution may tell us very little of their origins. This is why different groups of scientists believe that dogs variously originated in eastern Asia, Mongolia, Siberia, Europe or Africa.

    But why were the animals domesticated in the first place? The most recent theory is that dogs domesticated themselves, initially living in and around our ancient villages to eat any food thrown out. Today, this is a way of life still shared by three -quarters of a billion unowned dogs worldwide.

    Camping -Yellowstone National Park

    Camping rules

    Camping or parking in picnic areas, picnic grounds，or any place other than a designated (指定的) campground is not permitted. However, camping is often allowed in neighboring communities and forests outside the park.

    Camping is limited to 14 days between June 15 and September 15 and to 30 days the rest of the year. Check - out time for all campgrounds is 10:00 am.

    Quiet hours

    Camping in Yellowstone is a special experience. Each visitor deserves the opportunity to hear the birds, wildlife, and streams in this beautiful environment. Respect the rights of other campers and obey the law by keeping quiet from 8:00 pm to 8:00 am. No noises will be allowed during this time.

    Golden Age/ Golden Access discounts

    Holders of Golden Age and Golden Access permits will be given about 50% discounts on camping fees.

    Croup camping

    Group camping are permitted at Madison, Grant and Bridge Bay campgrounds from late May till the closing date for large organized groups with a designated leader such as youth groups or educational groups. The fees change per night, depending on the size of the group. Advance reservations (预定) are required and can be made by calling (866) 439 -7375.

    Around three forty-five on a rainy Saturday morning, I was woken up by the sound of my pager(呼机) beeping. As a volunteer firefighter and emergency medical technician, I can never count on a full night of sleep. I pulled myself out of bed and went toward the desk to grab my radio. Our crew was being sent to a nearby home where a man was in cardiac arrest (心脏骤停). We found the man lying on the kitchen floor with his wife beside him. We rushed the patient to the hospital, but despite our efforts, we were unable to save his life.

    In my line of life, I rarely get any recognition from the patients we treat, or from their loved ones. But that night, a man's wife approached us, and through her tears, whispered, “Thank you.” Then she hugged each of us. She knew we answered her late-night call for help, even though the ending was not positive.

    There is something deeply rewarding about helping people in these circumstances. Sometimes, I'm able to make their worst day a bit better: like seeing the tears of an injured child turn into a smile when I gave him an interesting toy; or watching a terrified mother's screams turn into tears of joy when she realized her baby was going to be fine.

    Experiences like these allow me to see the impact my work has on others. At the same time, I also know the effect it has had on my own life. As a teenager, I felt awkward when my dad hugged me and said, “ I love you, my dear son.” I was equally uncomfortable and responded, “I love you.” But then I imagined him lying on the kitchen floor that rainy night and realized that my opportunity to say those three words could—at any moment—be taken away forever. Now, I extremely treasure the moment when my father says those three words to me. I've learned to appreciate every relationship I have, to tell people I care about them, and to never take anything in life for granted.

    Barbara McClintock was one of the most important scientists of the twentieth century. She made important discoveries about genes and chromosomes (染色体).

    Barbara McClintock was born in 1902 in Hartford, Connecticut. Her family moved to the Brooklyn area of New York City in 1908. Barbara was an active child with interests in sports and music. She also developed an interest in science.

    She studied science at Cornell University in Ithaca, New York. Barbara was among a small number of undergraduate students to receive training in genetics in 1921. Years later, she noted that few college students wanted to study genetics.

    Barbara McClintock decided to study botany, the scientific study of plants, at Cornell University. She completed her undergraduate studies in 1923. McClintock decided to continue her education at Cornell. She completed a master's degree in 1925. Two years later, she finished all her requirements for a doctorate degree.

    McClintock stayed at Cornell after she completed her education. She taught students botany. The 1930s were not a good time to be a young scientist in the United States. The country was in the middle of the great economic Depression. Millions of Americans were unemployed. Male scientists were offered jobs. But female geneticists were not much in demand.

    An old friend from Cornell, Marcus Rhoades, invited McClintock to spend the summer of 1941 working at the Cold Spring Harbor Laboratory. It is a research center on Long Island, near New York City. McClintock started in a temporary job with the genetics department. A short time later, she accepted a permanent position with the laboratory. This gave her the freedom to continue her research without having to teach or repeatedly ask for financial aid.

    By the 1970s, her discoveries had had an effect on everything from genetic engineering to cancer research. McClintock won the Nobel Prize for Physiology or Medicine in 1983 for her discovery of the ability of genes to change positions on chromosomes. She was the first American woman to win an unshared Nobel Prize.

Simply being quiet is a growing appeal. Lots of business have appeared to meet a rising demand for quiet time, from silent weekend getaways to silent dining, silent reading parties and even silent dating. Silence can mean different things to different people. We are usually silent only with those closest to us. So there is something almost radical(不同凡响的)about the recent trend towards enjoying silence with strangers.

Mariel started a regular silent reading party in Dundee just under a year ago. Readers bring their books and meet in a bar, where they read together in silence for an hour or sometimes two and then put their books away to chat and have a drink. "When the reading party starts, everything goes quiet," says Mariel," It's a little bit surreal (超现实的), especially in what is usually a noisy bar. However, there is something special about sharing the silence with others. It offers a chance to escape from reality; everyone is so busy with work and with technology being ever present. An event like this gives people the opportunity to escape these things for a while."

Honi Ryan is an artist based in Berlin who began hosting silent dinner back in 2006. The rules of the dinner are: no talking, no using your voice, no reading or writing, trying to make as little noise as possible, not connecting with technology, and staying for at least two hours. So far she has taken her silent dinner project to Mexico, the US, Australia and China. "It's evident that the age-old connections we make over food do not depend on the words around it. Silence creates the space for the people and places involved to fill with whatever is needed; it is quite different from our usual social behaviors."

According to a 2018 report, people aged between 16 and 24 make up about 15 percent of the population but only 10 percent of museum-goers. Similarly, people aged over 35 go half as much as you would expect from their population size. We have reached the point of recognising the disconnection between art and the audience but haven't yet determined how to bridge the gap. Two answers to tackling this challenge lie in telling a greater diversity of art histories and communicating these stories in more accessible ways.

In 2018, a radio program called Art Matters was started with the aim of discussing art from a pop-culture viewpoint with topics that would engage younger and more diverse audience. It offers an accessible pathway to art history with conversations on different topics. Art history is about storytelling; art content shines when there is an effort to bring audience along for the discussion.

More traditional institutions are paying attention. Recently the Getty Museum issued a social-media challenge for people to recreate paintings using items they had at home. Users displayed incredible creativity, and the museum was flooded with submissions. This reaction proves that there is a potential desire for the audience to engage with art topics if the format is appealing. Since many people feel intimidated and think that there's a base level of understanding required to join the conversation, the Getty initiative serves as a reminder that there are many pathways to engaging with it.

Another result of the Getty challenge was the exposure given to a diversity of artworks. The famous opera singer Peter Brathwaite, for example, made scores of attractive recreations highlighting centuries of black paintings. His efforts opposed the idea that there were not many historical paintings of black figures. It is extremely important that we do a better job of showing the complex and diverse stories that are represented in art. 

Social media have offered a platform for people who have not traditionally had a seat at the table. Anyone can recognise a gap in the field and address it. Accounts have gathered tens of thousands of followers. They are the proof that there is hunger to hear these art histories, and these themes work brilliantly for museum programming.

But there is only so much that can be done without the museums and galleries changing meaningfully from within. We need to see a better balance of these stories represented in permanent collections. We also need a much wider diversity of people and interests represented on board. Ensuring that art—and writing and talking about art—is able to continue on the rising generation of storytellers, inside and outside of institutions, getting the funding and support they need to paint a brighter picture for the part.