As infants, we can recognize our mothers within hours of birth. In fact, we can recognize the {#blank#}1{#/blank#} of our mother's face well before we can recognize her body shape. It's {#blank#}2{#/blank#} how the brain can carry out such a function at such a young age, especially since we don't learn to walk and talk until we are over a year old. By the time we are adults, we have the ability to distinguish around 100,000 faces. How can we remember so many faces when many of us find it difficult to {#blank#}3{#/blank#} such a simple thing as a phone number? The exact process is not yet fully understood, but research around the world has begun to define the specific areas of the brain and processes {#blank#}4{#/blank#} for facial recognition.

Researchers at the Massachusetts Institute of Technology believe that they have succeeded in {#blank#}5{#/blank#} a specific area of the brain called the fusiform face area (FFA), which is used only for facial recognition. This means that recognition of familiar objects such as our clothes or cars, is from {#blank#}6{#/blank#} in the brain. Researchers also have found that the brain needs to see the whole face for recognition to take place. It had been {#blank#}7{#/blank#} thought that we only needed to see certain facial features. Meanwhile, research at University College London has found that facial recognition is not a single process, but {#blank#}8{#/blank#} involves three steps. The first step appears to be an analysis of the physical features of a person's face, which is similar to how we scan the bar codes of our groceries. In the next step, the brain decides whether the face we are looking at is already known or unknown to us. And finally, the brain furnishes the information we have collected about the person whose face we are looking at. This complex {#blank#}9{#/blank#}is done in a split second so that we can behave quickly when reacting to certain situations.

Touring Cenotes

    My parents and I traveled to Mexico to visit my grandparents last summer, and we visited the cenotes (say-NO-tays), the natural swimming holes located on the Yucatán Peninsula. The term "swimming hole" might make you think that cenotes are just average, but cenotes are truly {#blank#}1{#/blank#}. I had the most exciting experience of my life exploring these wonders of nature.

    Thousands of years old, the cenotes formed and created sinkholes underneath. Though the ancient Mayans (玛雅人) used the cenotes as water {#blank#}2{#/blank#}, people can now swim, dive, take photographs, and admire local trees and {#blank#}3{#/blank#} life, all through water as clear as liquid diamond.

    In Cenote Azul, my parents, my grandparents, and I swam through water that seemed too blue to be real. I {#blank#}4{#/blank#} countless younger kids diving into the water from a small cliff, but I dared not to jump at first. I finally worked up the courage, and my {#blank#}5{#/blank#} try instantly put all my worries to rest.

    A few days later, we went to Cenote Ponderosa. We stayed in the sun-covered pond, where we {#blank#}6{#/blank#} floated while others did diving and took underwater photographs. Being surrounded by a valley of trees made everything else in the world seem to disappear.

    Grutas de Loltún were definitely the most magnificent of all the cenotes, even though there was no swimming involved. Grutas are caves, and the Grutas de Loltún are among the biggest caves on the entire Peninsula. Our guide, Carolina, walked us through several caves, where we saw many drawings thousands of years old on the cave walls! Just one brief look at those drawings made me feel like I had stepped back in time to a(n) {#blank#}7{#/blank#} era of history. Our group thought Carolina was joking when she claimed she could make the stalagmites(石笋) sing for us, but when she {#blank#}8{#/blank#} them, we heard what sounded like the words "Lol" and "Tun"—the name of the caves! I cannot imagine that a(n) {#blank#}9{#/blank#} played at a concert at Carnegie Hall would have been any better.

    Mexico's Yucatán Peninsula is filled with beauty, but the cenotes are a one-of-a-kind opportunity to commune with nature in a way that is impossible anywhere else on Earth, and I would not {#blank#}10{#/blank#} to do it all again.

    Today, the events {#blank#}1{#/blank#} in realistic-looking or-sounding video and audio recordings need never have happened. They can instead be {#blank#}2{#/blank#} automatically, by powerful computers and machine-learning software. The catch-all term for these computational productions is "deepfakes".

    The term first appeared on Reddit, a messaging board, as the username for an account which was producing {#blank#}3{#/blank#} videos. An entire community {#blank#}4{#/blank#} up around the creation of these videos, writing software tools that let anyone automatically {#blank#}5{#/blank#} one person's face onto the body of another. Reddit shut the community down, but the technology was out there. Soon it was being applied to political {#blank#}6{#/blank#} and actors.

    Tools for editing media {#blank#}7{#/blank#} have existed for decades—think Photoshop. The power and peril of deepfakes is that they make fakery cheaper than ever before. Before deepfakes, a powerful computer and a good chunk of a university degree were needed to produce a realistic fake video of someone. Now some photos and an Internet connection are all that is required.

    The consequences of cheap, widespread fakery are likely to be {#blank#}8{#/blank#}, albeit slow to unfold. Plenty worry about the possible impact that believable, fake footage of politicians might have on civil society—from a further loss of trust in media to the {#blank#}9{#/blank#} for electoral distortions. These technologies could also be deployed against softer targets: it might be used, for instance, to bully classmates by creating imagery of them in embarrassing situations. In a world that was already saturated with {#blank#}10{#/blank#} imagery, deepfakes make it plausible to push that even further.