Welcome to Altmetric’s “High Five” for September, a discussion of the top five scientific papers with the highest Altmetric scores this month. On a monthly basis, my High Five posts examine a selection of the most popular research outputs Altmetric has seen attention for that month.
There really isn’t a theme this month to the articles that have seen the most attention via Altmetric, other than cool research!
Paper #1. Evidence of Water on Mars
“We seem to discover water on Mars about once a year. Well, that’s not quite true: We’ve known Mars has water for quite a while. However, there are a lot of mysteries still to solve about how that water behaves and where it’s located.” – Matthew Francis, The Daily Beast
Our top paper this month details the discovery of hydrated salts, i.e. salty water, on Mars! “Spectral evidence for hydrated salts in recurring slope lineae on Mars” was published in Nature Geoscience on September 28, 2015, and was followed by a flurry of news stories, blog posts and tweets.
“The authors analyze the composition of recurring dark streaks surrounded by brighter terrain, suggestive of the presence of moisture. Think about how wet concrete is darker than dry concrete. Using spectroscopic techniques, the scientists found traces of hydrated salts in all streaks (lineae) investigated, showing that the phenomenon coincides with warmer weather: Mars warms up, water flows down the slopes, carrying salts with it. Mind you, these are no waterfalls, just somewhat moister soil.” –Marcelo Gleiser, NPR
According to the study, “[r]ecurring slope lineae, narrow streaks of low reflectance compared to the surrounding terrain, appear and grow incrementally in the downslope direction during warm seasons when temperatures reach about 250–300 K, a pattern consistent with the transient flow of a volatile species.” Spectral data revealed hydrated salts, or very salty water.
And what good is any Mars story without the mention of the possibility of Martian life! But while evidence of liquid water makes Mars one of the more promising places to look for extraterrestrial life in our solar system so far, there are still 2 large barriers to overcome if we are to find it: 1) Any martian life would need to be able to withstand the high salinity of the water that likely flows on Mars; 2) The need to protect Mars from any possible Earthly microbial contamination makes it very difficult for us to go look.
“The excitement of finding liquid water on Mars is related to the correlation between water and life. If we want to find life on other planets, a great starting point is to first find water. Unfortunately, high salinity is not good for life. Even so, there may be variations in the saline content of different streaks, and some may be lower. As always with a new possibility, we will only know if we look.” –Marcelo Gleiser, NPR
Read Maddie Stone’s awesome article on what kind of life forms COULD exist in the extreme environment that Mars presents. She quotes NASA astrobiologist Chris McKay: “There are brines on Earth that are too salty for life. The most famous is Don Juan Pond in Antarctica. This [Martian] brine is even saltier than the calcium chloride brine in Don Juan Pond.”
Of course, extreme salt-loving and cold-loving martian microbes are still a possibility…
“Basically, our Martian microbes would have to get over the fact that Mars is a a toxic, radiation-filled wasteland.” – Maddie Stone, Gizmodo
- NASA finds its “strongest evidence yet” that water flows on Mars, Quartz
- Why a briny mars is exciting, but isn’t necessarily good news, Weird Things Blog
- Water flows on present-day Mars: Direct evidence found that water is involved in summertime darkening of Martian soils, by John Timmer, Ars Technica
Paper #2. How many trees are there in the world?
Our next top paper this month is “Mapping tree density at a global scale,” published in Nature. Check out this Nature video about the study.
“We provide the first spatially continuous map of forest tree density at a global scale. This map reveals that the global number of trees is approximately 3.04 trillion, an order of magnitude higher than the previous estimate. […] Based on our projected tree densities, we estimate that over 15 billion trees are cut down each year, and the global number of trees has fallen by approximately 46% since the start of human civilization.” – Crowther et al. 2015
Writers from over 70 news outlets and 30 blogs covered the study this month. The Guardian headlined: “Scientists reveal there are 3tn [trillion] trees in the world: Most accurate count to date is over seven times as many as the last estimate – but almost half have been cut down since the start of civilization, say scientists.” Many news outlets featured the new global tree count, three trillion trees, but pointed out that there might be at least twice as many trees today if it weren’t for human influences.
“The new research published in Nature will help improve our understanding of the role trees play in ecological and biogeochemical processes not just in the Amazon but across the globe. This knowledge could help inform management practices for the remaining forests. But perhaps its greatest impact will be the realization that the emergence of civilization has led to the net destruction of nearly three trillion of Earth’s trees. That could serve as a powerful perspective for comprehending the impacts humans have had on the natural world.” – James Dyke, The Conversation
The Guardian quotes Dr. Simon Lewis, geographer at the University College London and University of Leeds, regarding the new study: “To me it is more the first robust estimate of the number of trees. It’s an important and useful piece of work but we should remember that the number of trees is not necessarily the best metric for measuring the health of an ecosystem or its importance. A plantation of many of the same trees isn’t the same as a patch of Amazon rainforest.”
A blogger over at Nothing in Biology Makes Science paused to appreciate the methods used to reach the new estimate of 3 trillion trees on Earth: “The new estimates were reached by merging two separate mechanisms for tree sampling-satellite observation and ground-based ecological work. It is a tremendous study using 429,775 measurements from around the globe.”
Paper #3. Turning Snapshots into Painterly Masterpieces
Our third top paper this month is “A Neural Algorithm of Artistic Style,” published on arXiv.org this month. This study got a huge response on Twitter, and a handful of news and online outlets covered it as well. Mike Murphy over at Quartz wrote:
“Computers are learning how to write sonnets, compose classical music, and now they’re mastering another high art form: painting. Researchers from the University of Tubingen in Germany recently published a paper on a new system that can interpret the styles of famous painters and turn a photograph into a digital painting in those styles.”
So if you wake up tomorrow to find an updated Instagram filter that turns your snapshots into Picasso paintings, you can thank researchers Leon Gatys, Alexander Ecker and Matthias Bethge, authors of the study “A Neural Algorithm of Artistic Style.” Then again, you’d have to wait over an hour for the Instagram filter to convert your snapshot into such a masterpiece, with this particular algorithm.
According to an article in The Guardian, “[t]he algorithm forms a ‘convolutional neural network’ (CNN) which, in lay terms, uses object recognition to recreate the foundation image (which can be anything) in the style of a piece of specific art.”
“We introduce an artificial system based on a Deep Neural Network that creates artistic images of high perceptual quality. The system uses neural representations to separate and recombine content and style of arbitrary images, providing a neural algorithm for the creation of artistic images.” – Gatys, Ecker and Bethge, 2015
Paper #4. Chickens… Walking Like Dinosaurs
Our next top paper this month according to Altmetric data is a PLOS One paper on how chickens equipped with artificial tails provide clues about dinosaur locomotion. The study is actually not new – it was published in 2014. But the authors who published the study recently won an Ig Nobel award for their research, a yearly prize that celebrates serious scientific research that makes “people laugh, and then think.”
“Yes, it looks like a chicken with a plunger on its rear end, but the researchers concluded that its strut was ‘consistent with’ how dinosaurs would have walked. Specifically, how a two-legged non-flying dinosaur, such as a Tyrannosaurus Rex, might have gotten around.” – Cara Mcgoogan, Wired
Bethany Brookshire wrote a fantastic story about the study last year at ScienceNews, “A weighted butt gives chickens a dinosaur strut.”
“Bruno Grossi and colleagues at the Universidad de Chile were looking to learn more about how dinosaurs may have walked. While one modern relative of dinosaurs, the crocodilians, walks on four legs, birds — feathery descendants of the Tyrannosaurus rex we know and love — walk on two. This means that birds might be a good model to study to understand how bipedal dinosaurs moved as they stomped across the Mesozoic landscape. But there’s a big difference between most modern birds and the great land-bound dinosaurs: Dinosaurs had tails.” – Bethany Brookshire, ScienceNews
- 7 scientific studies that are too weird to believe, Business Insider
Paper #5. Your Plastic Waste is Hurting the Birds
Our final High Five paper is titled “Threat of plastic pollution to seabirds is global, pervasive, and increasing.” It was published in PNAS this month.
“We used a mixture of literature surveys, oceanographic modeling, and ecological models to predict the risk of plastic ingestion to 186 seabird species globally. Impacts are greatest at the southern boundary of the Indian, Pacific, and Atlantic Oceans, a region thought to be relatively pristine.” –Wilcox, Sebille & Hardesty, 2015
Media organization and blogging networks covered the study extensively, largely from an environmental impact and wildlife impact angle. Maddie Stone wrote for Gizmodo: “A new study on seabirds has come to a disturbing conclusion: Their bellies are filled with plastic. Up to 90% of marine birds alive today may have ingested plastic, and by 2050, that number could be as high as 95%.”
“Recently, a team of scientists used a mixture of literature surveys, oceanographic modeling, and ecological models to predict the risk of plastic ingestion for 186 seabird species globally. The study found that seabirds are most vulnerable at the southern boundaries of the Indian, Pacific, and Atlantic Oceans. The area that is predicted to have the highest plastic ingestion rates is the northern band of the Southern Ocean. Surprisingly, this region does not correspond to the areas of highest debris concentration, but rather corresponds to the area with the highest diversity of seabird species.” – Ars Technica
- Nearly all seabirds will have plastic in their stomachs by 2050, Quartz
- Nearly Every Seabird on Earth Is Eating Plastic, by Laura Parker, NatGeo