Top Ten Science Stories of 2015

urlThis is always a great time of year for list junkies like me. After consulting similar lists over at Science, Scientific American, Discover Magazine, and Science News, among others, I’ve once again decided to rank the ten biggest science stories of the past calendar year. Just like last year and the year before that, this year’s list comes with the standard reminder that I am not a scientist. I am an historian by trade, and I sometimes blog about contemporary science as a hobby. Also, before I get to my totally subjective list, I thought I’d mention a few of the stories that didn’t make the cut.

  • Back in January, Science published a special issue on “The End of Privacy.” Crazy that the death of privacy doesn’t even make my top-ten list, but I guess that’s the Brave New World in which we now live.
  • In June, scientists reported the discovery of an air bubble that formed in Antarctic ice more than a million years ago. The entombed sample allowed them to directly test the composition of Earth’s ancient atmosphere. Read their report here.
  • On July 2, scientists reported that they had finally resolved the anatomy of Hallucigenia, the bizarrely shaped and awesomely named “poster child” of the Cambrian Explosion. As if on cue, the Grateful Dead played the final three shows of their long career over the next three nights.
  • Later that same month, Russian billionaire Yuri Milner pledged $100 million to fund a robust search for extraterrestrial intelligence. Money well spent, in my humble opinion. Learn more here, here, and here.
  • In October, a group of scientists reported that they may have found the earliest evidence of life on Earth. Stay tuned for updates from peer review.
  • That same month, scientists reported that they had unearthed unequivocally human teeth from a cave in China that date back approximately 100,000 years. The discovery challenges the majority opinion, which holds that anatomically modern humans first arrived in China within the past 60,000 years. You can learn more at this link.
  • As for the top ten…


10. Nations of the World Pledge to Address Climate Change
9. United States and Iran Sign Nuclear Treaty
Both of these developments signal that the people of planet Earth are ready to start thinking as a species. Here’s hoping everyone everywhere understands that we need to successfully resolve these two issues, climate change and nuclear proliferation, if we want humans to survive for generations hence. To learn more on the Paris Agreement, check out the links here and here. For more on the Nuclear Treaty, check out the links here and here.

8. Spots on Ceres
This year, NASA’s Dawn spacecraft became the first human-made object to ever visit Ceres, the largest object in the asteroid belt between Mars and Jupiter. Without question, the dwarf-planet’s most tantalizing feature is the pair of surprisingly bright spots featured in the image overhead. When I first saw those spots, I was all but certain that we had discovered a benevolent extra-terrestrial civilization with whom we could become best buds, but it now looks like these spots are just salt deposits. Maybe not as dramatic as alien life, but curious and tantalizing nonetheless. For all the latest, check out this link.

7. Developments in Artificial Intelligence
Artificial Intelligence (AI) grows more sophisticated every single day. This year saw rapid advances in machine learning and language translations. It saw scientists debate the potential benefits of synthetic psychologists and the seemingly inevitable biotechnological convergence of computer science and brain science. To learn more, check out Science magazine’s recent special issue devoted to AI. If you’re concerned that AI could ultimately turn against humans (a la The Animatrix), you are, at the very least, not alone. A few weeks ago, Elon Musk joined with several other titans of industry to establish a billion-dollar research center that will, hopefully, prevent AI from usurping humanity. Speaking of best intentions potentially going awry…

6. GMO Kill Switch
In January, scientists published two different reports detailing how they had cultured a population of bacteria that was wholly dependent on human-created (and human-provided) amino acids that do not otherwise occur in nature. The achievement was billed as an evolutionary “kill switch” that could prevent genetically modified organisms (GMOs) from escaping the laboratory. I think this is a major development in humanity’s purported “control” of nature, and that it may yet foretell a new chapter in the human-dominated Anthropocene. That being said, it also reminded me of this classic scene from Jurassic Park, in which Jeff Goldblum and B.D. Wong discuss the feasibility of entirely human-dependent organisms.

5. Fish beneath the Arctic Shelf
In January, scientists reported that they had discovered a thriving ecosystem in one of the least likely places on Earth. After lowering a camera into a sliver of water trapped trapped beneath more than 500 miles of Arctic ice, they were stunned when a translucent fish swam into view. It is not at all clear how these complex vertebrates survive when they are so far removed from food webs on the surface (or in the ocean) that ultimately rely on the sun. Whatever the explanation, this discovery strikes me as yet another reason that we should ignore Arthur C. Clarke’s ominous warning from 2010 about celestial taboos (seen at the 2:00 mark in this clip) and send the Clipper spacecraft to Europa post haste.

4. Biosynthetic Roses
Most modern rose cultivars are bred for traits like color and appearance, and, as a result, many of the most popular strains have almost none of the rose’s iconic fragrance. That may now change. Back in July, a team of scientists announced that they had discovered the precise “enzymatic pathway” that produces the rose’s famous smell (PDF here). I confess there’s something inherently un-romantic about manufacturing the rose’s famously intoxicating scent in a lab, but it’s hard to argue with results. Speaking of which, a different team of scientists shocked the world last month when they announced that they had grown conductive wires within living roses. You read that correctly. The plants absorbed a specially designed soluble gel that hardened into flexible wires after being circulated throughout the rose. You can learn more here and here.

3. Transgenic Salmon
Last month, the U.S. Food and Drug Administration approved an intensely managed population of genetically engineered salmon for human consumption. Unlike their wild counterparts, these deliberately cultivated salmon are transgenic, which means they contain sections of DNA from other species. As you may have already surmised, these genetic additions promote expeditious growth. Remarkably, the wild salmon (foreground) and transgenic salmon (background) pictured overhead are the same age. These salmon were first cultivated more than twenty years ago, but concerns about the animals’ potential impact on human health and food webs successfully stalled approval until now. This marks the first time that transgenic animals will enter the market in U.S., so if not buyer beware, then, at the very least, buyer be aware. To learn more, check out the links here and here. Of course, the buyer should also be aware that the entire controversy over transgenic animals already looks quaint when compared to the discovery that headlines this list.

2. First Visit to Pluto
In July, the New Horizons spacecraft became the first human-made object to visit Pluto, that lovable-underdog planet (or dwarf-planet, depending on whom you ask) inhabiting the distant Kuiper Belt region of the solar system. To cover the intervening 4.6 billion miles in a mere ten years, the spacecraft had to travel more than 50,000 mph, and was thus traveling way too fast to fall into orbit around Pluto. Despite the brief visit, New Horizons got some truly amazing images (examples here and here). What makes them amazing? Pluto is the farthest destination that humanity’s recon robots have ever visited. Cooler still? The New Horizons spacecraft is now en route to another chunk of rock even deeper in space. (Bonus trivia: New Horizons also captured some truly outstanding images of the Jovian system when it picked up a gravity boost from Jupiter back in 2007.)

1. Scientists Use CRISPR to Edit Human Embryos
I knew what the biggest science story of the year was going to be as soon as it was first reported back in April (links here and here). As I mentioned at the time (original post here), a group of scientists in China announced that they had used CRISPR-Cas9 technology to intentionally edit the DNA of several dozen human embryos by deliberately introducing certain kinds of genes. Roughly a quarter of the embryos incorporated the new genes and divided into blastula, as embryos are wont to do. All of the experimental embryos possessed a genetic disorder that prevented any of them from developing to full term, but that has hardly silenced the chorus of concerns. Many scientists in the United States have called for a moratorium on using CRISPR to edit the human germ line, but just as many are eager to move forward. Earlier this month, representatives from the National Academy of Sciences (U.S.), the Chinese Academy of Sciences, and the Royal Society (U.K.) held an international summit in Washington DC to discuss the ethics of editing human embryos. The summit’s participants ultimately urged caution (you can read their report here), but it’s no secret that humans have a pretty spotty track record when it comes to forbidden fruit. I’ll write more on this topic at a later date, but, for the time being, readers should know that CRISPR will not only revolutionize the biological sciences, but may also transform the biotic composition of the planet, humans included. To learn more, check out the links here, here, and here.