What do you usually do to comfort your friends when they are feeling sad or depressed ? You probably pat them on the back or shoulder , or maybe you give them a big , warm hug . We used to think that knowing when and how to comfort others was an ability that only humans have . But scientists have discovered that apes have this ability , too , according to a study published in the Journal of the Proceedings of the National Academy of Sciences . Two researchers from Emory University in Atlanta , US , went to an Ape Protection Centre in Congo to study bonobos , which are closely related to humans . The researchers analyzed the bonobos' reactions after more than 370 cases of stressful situations , such as fights and losing temper , and found that some bonobos rushed to hug those that were screaming after being attacked , just like humans would have done . However , researchers noted hat not all bonobos were capable of comforting others . In the protection centre , many bonobos are orphans whose mothers were killed by hunters . They were found to be more anxious in times of tension and to have greater difficulty controlling their own emotions , making them worse at reaching out to help friends in need . " Orphans , who have not had the benefit of a mother helping them handling their emotions , are much worse at comforting others , " Professor Frans de Waal , one of the researchers , told The Telegraph . " Bonobos with moms were able to curb their negative emotional reactions more quickly . Therefore , they pay more attention to others . " This pattern mirrors the way that human children have been found to react . Those who seem more capable of handling their own emotions - for example , the ones who can calm themselves down more quickly after upsetting experiences - are usually better at expressing their concerns for others . What's the main purpose of this passage ?
To inform readers of a new study . To uncover the mystery of Apes . To provide better protection for Apes . To compare human behaviors with Apes' .