Staring into your puppy's eyes can release a "love hormone" By Scientific American, adapted by Newsela staff on 11.28.17 Word Count 521 Level 560L A Weimaraner looks up with its puppy-dog eyes. Scientists are now saying that the stare dogs are known for is a result of thousands of years of evolution. Photo by: Pexels When your pet dog looks deeply into your eyes, something happens in your brain. A special chemical is released. The chemical is known as oxytocin. It is the same thing that makes mothers feel love for their babies. Oxytocin is a hormone. Hormones are like chemical messages in the body. They tell your body to do certain things. Oxytocin sends messages to the brain. It changes how we feel. Oxytocin is sometimes called "the love hormone." When we hug someone we love, oxytocin levels increase. This creates feelings of happiness and trust. The release of oxytocin in the brain is part of a cycle. When more is released, more is produced. This article is available at 5 reading levels at https://newsela.com. 1 As your dog looks into your eyes, oxytocin floods your brain. The chemical makes you feel love for your pet. At the same time, oxytocin is also released in your dog's brain. It feels love for you. Now the two of you are tied together by feelings of love. Studying Dingo Behavior It took thousands of years for dogs to develop their long, loving looks. A new study says this staring came about in stages. The first stares were quick. They probably didn't have much effect on people's feelings. The new study was led by scientist Angie Johnston. It looked at dingoes. These doglike animals are similar to both dogs and wolves. Dingoes began hanging around humans 30,000 years ago. They originally lived in Asia. Around 9,000 years ago, several were brought along on a journey. They were taken to Australia. Once in Australia, dingoes slowly became wild again. In time, they stopped living around humans. It was only after this that people began breeding dogs. A Short Amount Of Eye Contact Johnston says dingoes are similar to the earliest dogs. Over time, breeding changed the way dogs look and act. Breeding is how humans have gotten dogs with specific traits. For example, some dogs were bred to work as herders. Other dogs were bred to be companions. Dingoes are still around today. They are similar to what dogs were like before any human breeding. So, by studying dingoes, scientists like Johnston can learn about what dogs may have been like long ago. For her study, Johnston looked at a group of Australian dingoes. She studied how the dingoes act with the people who took care of them. She wanted to see if they ever looked into their handlers' eyes. This article is available at 5 reading levels at https://newsela.com. 2 It turns out the dingoes did stare into their handlers' eyes. They only looked for a short time, though. Long Stares Took Time To Develop Johnston's study shows dingoes do make eye contact with people. So, early dogs probably did too. Johnston thinks doglike animals began making quick eye contact with people thousands of years ago. The longer dog stare came later, though. It took time to develop. The dingo stares were very short. They lasted just three seconds. Dog stares lasted around 40 seconds. How long does the stare have to last to create feelings of love? Scientists will need to keep studying in order to find out. This article is available at 5 reading levels at https://newsela.com. 3 Quiz 1 Read the section "A Short Amount Of Eye Contact." Select the paragraph that BEST explains how dogs became the way they are now. 2 Read the sentence from the section "Studying Dingo Behavior." It took thousands of years for dogs to develop their long, loving looks. Based on this sentence, which of the following statements is TRUE? 3 4 (A) Dogs looked at humans for a long time many years ago. (B) Dogs began to look at humans a very long time ago. (C) Dogs learned to like humans in the distant past. (D) Dogs first developed thousands of years ago. Which event in the article happened FIRST? (A) Dingoes started to live near humans. (B) Dogs started to look longer at humans. (C) Dingoes were taken to Australia. (D) Dogs were bred by humans. How do dog stares affect humans? (A) They start a chemical that makes humans feel loving. (B) They help humans understand what dogs want. (C) They change how humans show their feelings. (D) They affect the way humans take care of dogs. This article is available at 5 reading levels at https://newsela.com. 4