字幕列表 影片播放 列印英文字幕 Let's hear it for ears! As unique to us as our fingerprints are, these curly, bendy bits of cartilage - called pinna - have grown out the side of our heads for good reason. Back in the day, they helped us hunt by pinpointing which direction that rustling in the bushes was coming from. But perhaps most importantly, ears help us communicate with other human beings. Even before we emerge from the womb, we've decided whose voice we like most - it's our mammy's! And we've probably had a wee jive to her favourite songs, because our lugs are already listening when we're minus 20 weeks old. After we're born, our sticky-out ears become even more useful. They deflect sound towards your eardrum, keep your glasses from falling straight off your head, they help us to socialise, too. The inner workings of the ear heighten the frequencies of the human voice - so much so, that some scientists claim that listening to someone is a more effective way to recognise and decode complex human emotions than looking at their facial expressions. But if all the complicated goings-on seem to happen inside the ear, why do they stick out the sides of our heads instead of sitting on top like a bunny, or hanging low like an elephant? It often comes down to whether an animal is predator or prey. Predators, like foxes, have ears on the top of their heads that they can point down at the ground when hunting. This allows them to hear what poor wee animals are burrowing underground, dig down to get them, snack away. For animals that don't need to hunt, ears on the tops of their heads allow for better movement. A rabbit's ears can swivel 270 degrees and allow them to hear for up to 3km - meaning that they can be alert for predators while looking at dinner. Our old pal the African elephant has the biggest ears of any creature on Earth, making up about a fifth of their surface area. They use their giant lugs to fan themselves, while the thin skin does a great job of dissipating heat. Our external ears may not serve us so well on a hot day, but they can be an indicator of our health, and in the most peculiar way. It comes in the form of a diagonal crease on your earlobe called Frank's Sign. Benign as it may look, the appearance of Frank's sign has been linked to cardiovascular disease and diabetes. But scientists are stumped over why the crease appears and how it correlates to these diseases, just that it kind of... does. Now, while we're on the subject of earlobes, decorating them is nothing new, for humans at least. The oldest mummy ever found in Europe - Otzi the Iceman - had pierced ears. In modern times, because we're so damn edgy, we've found about 14 different ways to pierce our ears, each with their own name. The most fun of the bunch might be tragus. The word comes from the Ancient Greek tragos, meaning goat, apparently because the tuft of hair some people have coming from their ears looks like a goat's beard. If the idea of piercings makes you wince, cover your ears now and be glad you still have them, because if you were a criminal in 16th Century England, there was a chance your punishment would be cropping. That's where your ears were cut off to show the rest of the town who the delinquent was. You were even prescribed a haircut, so you couldn't hide your shame. For the uncropped, our ears never stop growing. Maybe good news if you've got eensy-weensy ears, but for the already large-lugged, they ain't going away and gravity is only going to make them get floppier as you age. Big or small, it's the shape and folds of your ear, and how the brain processes sound waves, that help us determine where a sound is coming from. So next time you lose your phone under the sofa, it's your twisty ear folds that are helping you to locate that Coldplay ringtone. Such sounds might be painful to hear - physically even, if they're over 130 decibels - but our strange wee ears give us lots to be thankful for. They allow us to hear our loved ones, and best of all, pretend not to hear them when you said you'd hang the washing out.
B2 中高級 為什麼你的耳朵是獨一無二的(而且令人驚奇!)|BBC創意。 (Why your ears are unique (and amazing!) | BBC Ideas) 99 2 Summer 發佈於 2021 年 01 月 14 日 更多分享 分享 收藏 回報 影片單字