Top Ten Science Stories of 2016

Every year around this time, I rank the biggest science stories of the year (previous lists here, here, and here), and every year, I offer the exact same disclaimer: I am not a scientist. I teach history for a living. The only thing that qualifies me to write this list is that, like you, I am trying to find my way in the midst of an ongoing (and accelerating) scientific revolution. Before we get to this year’s list, a few words about the runners-up…

This time last year, I ranked the use of CRISPR gene-editing technology on human embryos as the biggest science story of the year, but there have been many developments since then. In April, a second team of scientists (also based in China) reported that they too had used CRISPR to edit human embryos. This time, they introduced an HIV-resistant mutation and they claimed some success. Around that same time, the USDA cited legalese when announcing that it would not regulate CRISPR-edited organisms. Meanwhile, the battle for the CRISPR patent has really heated up as charges of sexism and subterfuge fly. At press, the U.S. Patent Office has not yet determined whether UC Berkeley or Harvard deserves the patent and the untold billions it will bring.

In September, a group of scientists reported evidence of life in rocks that are 3.7 billion years old. If the evidence holds up, this would be the earliest trace of life on Earth. Since we all have questions about the origin of life, and since we all have a stake in how those questions are purportedly answered, I encourage you to review their evidence for yourself here and here.

No matter when or how living things first appeared on this planet, they are now positively ubiquitous. This year I learned that no matter how deep humans dig into the Earth’s mantle, we always find life. As one scientist put it, “we have not yet found the bottom of the biosphere.” Think about that. Microbes live many miles beneath your feet, many miles from the closest sunbeam. Learn more here and here. Okay, on to the list…

10. Sending reconnaissance robots to Proxima Centauri
Last year, Russian billionaire Yuri Milner announced that he would commit $100 million toward the search for extraterrestrial intelligence. Last April, flanked by scientific luminaries like Stephen Hawking, Martin Rees, and Freeman Dyson, he announced that he was funding an unmanned mission to the Alpha Centauri star system, which is the closest star system in the universe to our own. The system actually contains three stars, the closest of which is Proxima Centauri (foreshadowing). Though still in its early stages, the mission, dubbed “Starshot,” would use Earth-based laser beams to direct a fleet of tiny space probes in the direction of Alpha Centauri at one-fifth the speed of light. At that blistering speed, the probes could reach the Alpha Centauri system in approximately 20 years.

9. USGS confirms humans are causing earthquakes
Oklahoma is now the most seismically active state in the lower forty-eight, and experts agree that human activities are to blame for the rising number of earthquakes. More specifically, they agree that increased oil and gas activities are causing the earthquakes. (Click here for more information.) It strikes me that humans really do represent a unique force of nature, and that we really are living in the Anthropocene.

8. Scientists create a synthetic organism with smallest genome
In 2010, entrepreneurial geneticist Craig Venter and his team announced that they had created the world’s first synthetic organism. This past March, they announced that they had produced a synthetic organism with the world’s smallest genome, just 473 genes. Despite trimming the bacterium down to its bare essentials, the scientists confess they don’t know what function a third of the genes serve. I realize there’s still an awful lot about genes that humans don’t understand, but I appreciate that scientists are trying to answer questions that have always interested me: What distinguishes animate matter from inanimate matter? When is something alive and when is it just a jumble of atoms?

7. Ancient astronomers tracked Jupiter
As a historian (or is it “an” historian? I can never remember), I am constantly reminded of how just how much we don’t know about history. Case in point, astroarchaeologist (now that’s a job title) Mathieu Ossendrijver published an article in Science last January showing that ancient Babylonian astronomers accurately charted the motion of Jupiter across the night sky more than 2,000 years ago. They etched their geometric calculations into cuneiform tablets, but the information was lost when cuneiform died out, and would not be rediscovered for another 1,300 years. This is an excellent reminder that science does not always move in a straight line, and that that ancient scientists were far more advanced than we tend to acknowledge.

6. Synthetic Human Genome Project
In May, more than 150 scientists, entrepreneurs, and policy experts convened a secretive meeting that was closed to the public and the press. Less than a month later, many of those same individuals announced plans to produce a completely synthetic human genome within the next ten years. To be clear, this means that they will use cutting-edge technology to construct human DNA from scratch. Once complete, the synthetic DNA could be implanted in an embryo. The resultant human could be tailored to your exact specifications, and the resultant human would not have parents. Whether you find this project noble or nightmarish, you need to understand that this is not science-fiction. This is real. In the immortal words of Penny Lane, “it’s all happening.”

5. Brain can retrieve lost memories
I have been alive for more than a billion seconds, and I can remember almost none of them. Luckily for absent-minded people like me, scientists are conducting a lot of really cool research on misty, water-colored memories. In July, a group of scientists announced that they had identified the mechanisms and molecules involved in the formation and storage of early-life memories. They successfully retrieved long-lost memories from infancy in lab rats, and they hope to eventually do the same for humans (click here for an explanation). Meanwhile, earlier this month, a different group of scientists announced that they had used noninvasive electromagnetic pulses to reactivate “forgotten” memories in test subjects.

4. Greenland sharks live for centuries
Whether we want to admit it or not, all of us are aging. Some people do it more gracefully than others, but none of us do it as well as Greenland sharks. Using radiocarbon dating, scientists recently announced that Greenland sharks, who live in the frigid depths of the Arctic and North Atlantic Oceans, can live for more than 400 years, and perhaps even longer. This makes them the planet’s longest-living vertebrates, but they remain veritable babes compared to trees, which can live for thousands of years. To learn more about the oldest living things on Earth, check out Rachel Sussman’s recent book on the subject.

3. Advances in treating paralysis
In April, scientists announced that they had helped a quadriplegic man regain movement in his hands. Attaching one set of electrodes to the man’s brain and another set to his arm allowed the brain’s electrical impulses to bypass his damaged nerve pathways. The injured man, 24-year-old Ian Burkhart, was not only able to move his fingers, but also showcased incredible dexterity. He was even able to play Guitar Hero! And that was not the only encouraging news this year. In October, scientists announced that implanting microchips into the brain of another paralyzed man, Nathan Copeland, allowed him to control a robotic arm with his mind, and, even more incredibly, allowed him to actually feel pressure in his own fingers when the robotic fingers were touched. Mr. Copeland even shared a terrorist fist jab fist bump with President Obama.

2. Growing human embryos for the longest time
Everyone who has ever lived began life the same way: as a zygote, a single fertilized egg. Each of us eventually cleaved into two cells, then four, then eight, then sixteen, and so on and so forth. For most of human history, conception and embryological development were concealed within the womb, but that is no longer the case. Ever since the widespread success of in vitro fertilization over the past forty years or so, many lives have been conceived in petri dishes. But embryos cannot survive in a petri dish forever, and they must be transferred into the mother (or surrogate) within a few days to remain viable. For years, laws have stipulated that human embryos shall not be cultured in a dish beyond 14 days for ethical reasons, but this dictate was never really challenged because rearing an embryo for that long had always proved impossible. That is no longer the case. In May, scientists announced that they had devised a new method of in vitro fertilization, and that they had grown human embryos in a lab for up to 13 days. This is a major achievement for the science of embryology and the practice of reproductive medicine, and many researchers now suggest revising the 14-day rule. Needless to say, this issue is fraught with ethical landmines. Rather than telling you what to think, I encourage to learn more at the links here, here, and here.

1. Exoplanet around Proxima Centauri
Five years ago, we knew almost nothing about exoplanets save for their scattered existence. Now, we know that there are hundreds of billions of exoplanets in our home galaxy. In fact, there are probably more exoplanets in our galaxy than stars. These are exciting developments, but the holy grail has always been finding an Earth-like exoplanet relatively nearby. This past August, astronomers announced that they had discovered an Earth-sized exoplanet orbiting Proxima Centauri, the aforemention star (see #10 above) that is closest to our Sun. More exciting still, the exoplanet falls within the so-called “habitable zone,” meaning water could potentially exist in a liquid state on its surface. Proxima Centauri is tantalizingly close, but sufficiently far away that it is utterly impossible for humans to travel there… for now. And so I’ll end 2016 on a hopeful note. As the late, great Carl Sagan once wrote, “astronomy is a humbling and character-building experience.” In that spirit, may the immense distance to Proxima Certauri remind the people of Earth how much we have in common, even as the star’s close proximity beckons us to one day visit.