Our ancestors, who lived tens of millions of years ago, could turn their ears to hear the sounds better, as today’s cats and dogs did. People lost this ability over time, and the muscles that once controlled the ear movement do not work mostly (except for a few people who still play their ears). However, new research shows that these muscles are still reacting when we listen carefully, which points to their old functions.

Researchers in Germany and the United States found that the muscles known as ear muscles, which were once used to move our ears, were still activated when we focused on different sounds. Although it is not yet known whether these muscles have improved our hearing capabilities today, the more we focus on listening to the new research, the more we use these muscles. Interestingly, these findings reveal a part of our body and a useful ability to disappear.

Andreas Schröer of Saarland University, leading to the study, said in a statement published in Frontiers magazine, “There are three large muscles that connect the auricle to his skull and scalp and are important for ear -playing. These muscles exhibit an increasing activity during the listening tasks that require upper ear muscle, effort. This shows that these muscles are activated not only as a reflex, but as part of a potentially part of the mechanism of effort, especially in challenging auditory environments. ”

Previous research associated the activity in the posterior and Superior ear muscles, the largest ear muscles, with careful listening, and suggested that our primate ancestors used them to move their ears and direct sounds to the eardrum. However, Schröer and his colleagues wanted to determine whether the muscles were more active when people had to listen more.

As explained in detail in the study published in Frontiers, the researchers put electrodes on the ear muscles of 20 participants without hearing problems and told them to listen to a voice book spreading from the speakers. The participants listened to the Voice Book at various levels of difficulty and eventually entered a test about their content. Sometimes the researchers were playing a podcast that distracted at the same time, and occasionally sounds came from different aspects, but according to the researchers, the task was always held in a difficulty. If the participant gave up because it was very difficult, the activity associated with the ear muscle effort ended.

As a result, researchers observed that posterior and superior auricular muscles show different activities depending on acoustic state. The more efforts the participants make to hear the audio book, the more Supeerior auricular muscles contract. In addition, when the audio book was played behind the participant, the posterior auricular muscles of the participants were activated to turn their ears in that direction if we still had this ability.

Schröer says that our ancestors have lost this ability about 25 million years ago because it is difficult to say exactly the reasons for losing the functions of these muscles, but a possible reason may be eliminated the need for these muscles because we have become more capable of our visual systems.