Out in the jungle, looking for a cave? Machine learning and lasers can help

New techniques are helping field researchers locate hard-to-spot caves

Gabriela Serrato Marks

Marine Geology

Massachusetts Institute of Technology

In densely vegetated tropical forests, caves can be incredibly difficult to find. The entrances are sometimes tiny, just big enough to squeeze into, or covered with branches and leaves. Even when you have exact GPS coordinates, caves that haven’t been visited in a while can blend into the rest of the environment. 

Leila Donn and other researchers walk past a rock wall, maybe near a cave.

Leila Donn (orange and blue gear) with other researchers walking past a cave wall.

Gabriela Serrato Marks

That means that it’s particularly difficult to find unmapped caves. Unfortunately, those undisturbed caves can also be the best places to find geological or archeological samples. That’s why Leila Donn, a graduate student at University of Texas - Austin, is trying to find a better way to search for caves. We first met last year, when we went caving in Belize. She’s a great caver because she is an accomplished rock climber, knowledgeable geologist, and pretty much completely fearless. I wasn’t at all surprised to hear that she had been finding caves in Belize that hadn’t been visited by humans for centuries. 

Although you may think that geologists just go out to the field with rock hammers and whack stuff, Donn’s work is extremely computational — she’s using machine learning to find the unmapped caves. Her approach combines LiDAR images (using lasers to create 3D maps) with other information about the terrain, like slope and distance to streams. Though the research hasn’t been peer reviewed yet, it has been tested (cave reviewed?): she successfully used the machine learning to find caves and sinkholes during a summer of ground-truthing. 

Stalactites and stalagmites in a cave.

Stalactites and stalagmites.

Gabriela Serrato Marks

Now that Donn knows her algorithm works, she’s going to add more training data and expand her analysis area. In the future, this research could be used to find more caves, but also to better manage wide swaths of forested areas. 

CRISPR technology for human gene editing is promising, but serious scientific and ethical concerns remain

Multiple sectors of society must be involved in the regulation and applications of CRISPR to medicine

Marnie Willman


University of Manitoba Bannatyne and National Microbiology Laboratory

CRISPR-Cas9 has received global attention for its potential to  eliminate genetic disorders, infectious diseases, and many other  ailments that plague humans (pun intended). But in the realm of science, when something seems too good to be true, there are often important caveats. The current standing of gene editing technologies leaves many scientists wondering if we know enough about the genome and consequences of “genetic tampering” to do it in the name of betterment of mankind. 

Recently, the US National Institutes of Health pledged $190 million to make gene editing more widespread. Last month, the story of a Russian couple, both of whom are deaf or partially-deaf and want to use CRISPR to genetically modify their embryos so that their future child is not, circulated around the world of science news. But we still do not know all of the potential adverse effects and consequences of gene editing human beings, leading some to argue that the regulation and applications of this important scientific technology cannot be left up to scientists.

The human genome is a complicated and intertwined set of information, and edits in one part of a gene may have downstream effects that we are currently unaware of. For example, gene editing can lead to large-scale deletions and rearrangements of genetic information that could lead to abnormal gene function and cell activity

While the ability to edit and change the human genome is appealing to virtually every branch of medicine, serious ethical, social, and policy concerns surrounding CRISPR and other gene editing technologies must be grappled with alongside their scientific promise. 

I want a new smartphone, but the human and environmental cost is giving me doubts

New gadgets are fun. They're also abysmally destructive

Cassie Freund


Wake Forest University

I need a new phone. Like many of us with older model iPhones, my battery life is just a few hours and I've stopped updating the operating system to extend the phone's life. But I'm having a tough time pulling the trigger. It's not the cost (although that is hefty, especially on a grad student salary). It's not the hassle either. It's the environment.

Making smartphones, laptops, and other tech takes a lot of resources. This is partly due to the carbon emissions from the manufacturing process, but the biggest toll comes from the mining of the rare earth metals that make your phone work. If you're reading this on your phone right now, you're holding about 0.034 grams of gold, 0.34 grams of silver, and smaller amounts of palladium, platinum, yttrium, terbium, and gadolinium — among others. These are tiny amounts, but consider the demand for smartphones around the world. 

All of these rare elements have to be mined from inside the Earth, in places like China and the Democratic Republic of Congo. Mining is hugely environmentally destructive: forests are decimated, the ground is disturbed, and water quality in the area takes a dive. Worse still, the cobalt mining industry in the DRC depends on child labor. And elsewhere in the DRC, mining for coltan, another smartphone ingredient, threatens a key population of Grauer's gorillas.

Now take these environmental risks, and combine them with the fact that the average lifespan of a smartphone is just two years, the length of your contract with your cell phone company. After that, if you're lucky, you get a "free" upgrade. Awesome, right? Sure, if you ignore the fact that the environmental impact of a new phone is about the same as using  your old one for a decade. 

The environmental impact of illegal gold mining in the Amazon

Planet Labs, Inc. / Wikimedia

It's nearly impossible to live in the 21st century without contributing to environmental destruction and climate change. I am guilty as well — I eat meat and occasionally fly. But that doesn't mean that we should stop trying to do better by our planet, or ignore the consequences of our actions. This Christmas, I urge you to think carefully about that smartphone purchase, not matter what the Black Friday ads are telling you. 

I know I am.

Win a chemistry-themed board game from Genius Games

We’ve joined forces with Genius Games to giveaway two of their chemistry-themed table-top games, Ion and Periodic. Enter through Saturday, 11/23 for your chance to win!

Allan Lasser

Co-founder and CTO, Massive Science

We’ve joined forces with Genius Games to give away their chemistry-themed table-top games, Ion and Periodic to readers of Massive Science.

Enter for your chance to win a copy for yourself or a friend! This giveaway will be open through Saturday, 11/23/19, so don't miss your chance.

We love how Genius Games combines fun, accessible games with fundamental scientific ideas and concepts. We're really excited to be able to be able to giveaway some of their games—but make sure to check out their entire collection, featuring games inspired by biology, chemistry, and history.

Soon, algae might absorb carbon dioxide emissions before they even leave the factory

Algae are efficient biofuel producers, and scientists are working on improving our algal-centered technology

Nikita Nandakumar T

Chemical Engineering

Syracuse University

Researchers are always working on developing technologies to reduce carbon emissions to deal with the climate crisis. Recently, algae bioreactor technology has been highlighted as a way to convert carbon emissions from industries into biofuel and other useful by-products. But cost-effective methods for doing just this are needed to speed up the rate at which these new technologies are adopted. 

Now, researchers at Pacific Northwest National Laboratory's (PNNL) Marine Sciences Laboratory in Sequim, Washington, aim to lower the cost of producing algae-based biofuels to $3/gasoline-gallon equivalent by 2030 by cultivating highly productive strains of algae. The PNNL's work on algal biofuels is funded and directed by the U.S. Department on Energy as part of the Algal DISCOVR project.

The algae technology eliminates challenges associated with existing carbon capture methods. Algae in the bioreactor use minimal resources: they depend solely on carbon emissions produced by industry and light to produce biofuel. Algae is thought to be 10-100 times more productive as compared to the non-food crops, such as switchgrass, used in current biofuel production. This means algae is capable taking up more carbon dioxide and producing more biofuel per acre, than these alternatives. Since they lack the tough fibrous structures of switchgrass and other plants, algae are also easier and cheaper to process. Other benefits of using algae for biofuel are that they don't take up agricultural land and don't require much water input.

Ideally, algal bioreactors could be installed in factories to capture the carbon dioxide as it is emitted. The company Hypergiant has already developed this type of reactor, which uses artificial  intelligence to continually monitor and adjust airflow, the amount of light and carbon dioxide, temperature, and other parameters to maintain the optimal conditions for algae growth. There is hope for our future to be green, yet.

New research points to a simple way to diagnose autism, even in non-verbal patients

Measuring the brain's ability to toggle between two images is highly correlated to the severity of autism symptoms in study participants

Sarah Anderson


Northwestern University

A recent study from researchers at Johns Hopkins University and Dartmouth College has identified a new marker for autism that could facilitate earlier diagnosis. The marker is a difference in the autistic brain’s capacity for binocular rivalry, which describes the visual cortex’s ability to process one image at a time when presented with multiple images at once. The brain's inability to ignore one of several competing stimuli is tied to the hypersensitivity to sensory input that is characteristic of autism.

Study participants were shown checkerboard patterns of different colors in their right and left eyes, and their visual processing of the images was measured through an electrode that picks up on brain signals. Autistic participants were much less able to toggle their focus between the two images, compared to neurotypical  participants. Amazingly, the researchers found that the rate of binocular rivalry they measured was predictive of the severity of one’s symptoms, and using the data they could diagnose autism in study participants with 87% accuracy. A clear benefit of this study is that this marker is non-verbal, which means it can be used to evaluate young children who have not started talking yet as well as non-verbal adults.  

While this work provides insight into the underlying neurological root of autism and establishes a new diagnostic tool, it’s important to remember that autism is not a problem to be solved. While the differences in the autistic brain may lead to social challenges, they also impart unique intellectual abilities.  

How did our ancestors start walking upright?

A newly discovered species of ancient ape could shed light on the origins of human bipedalism

Darcy Shapiro

Evolutionary Anthropology

Rutgers University

In a recent Nature paper, a team of paleoanthropologists announced the discovery of a new fossil ape from Germany, which they named Danuvius guggenmosi. Dating to 11.62 million years ago, this little (17-31 kg) ape seems to have had an previously unknown way of moving through the trees. 

One of the biggest open questions in paleoanthropology is how our ancestors evolved to walk upright. Our mode of locomotion, called obligate bipedalism, is unique among primates and our closest living relatives, the great apes, have very different ways of getting around.

Human ape skeletons

Gary Todd

So how did our last common ancestor with the great apes move? Were they upright, like us, or were they more reliant on using their arms, like the great apes?

The researchers who studied Danuvius suggested that it combined upright walking in the trees (aided by a grasping big toe) with the kinds of forelimb movements used by the great apes. They called this new kind of locomotor behavior "extended limb clambering" and wrote that it might be a potential candidate for the way the last common ancestor of humans and the great apes moved. 

They haven't yet analyzed how this new ape might fit into the family tree, but its fossils are still helping to shed light on a complicated time in our evolutionary past.  

Using the old-fashioned blueprint chemical process for modern art

The cyanotype printing process is not only still useful in the 21st century, it's still beautiful

Sarah Anderson


Northwestern University

Have you ever wondered why we call floor plans and other diagrams “blueprints”? The term “blueprint” originates from the cyanotype printing process, which yields prints in vivid cyan-blue colors and was widely used to replicate complex technical drawings in the 19th and 20th centuries. While cyanotype printing could have been made obsolete by the invention of copy machines, artists today continue to use this process to create startling cyan images. For example, photographer Takeshi Moro exclusively used cyanotype to produce pieces for his 2013 exhibition “Wannsee in Berliner Blau.” The crude quality of the images was meant to transport the patrons to the time of the 1942 Wannsee Nazi Conference, and their blue hues were intended to invoke the sorrow of this era of history.  

A cyanotype of algae done by Anna Atkins.

An example of cyanotype of algae done in the 19th century by Anna Atkins

New York Public Library

I helped Takeshi to develop images for the exhibition by making the cyanotype solution in the lab. I combined two chemicals, ferric ammonium citrate and potassium ferricyanide, at a fixed ratio. Takeshi then applied the solution to the photographic prints and exposed them to light (the duration of this exposure period and the intensity of the light will affect the contrast of the image). Together, the light and the citrate cause the iron atoms in the ferric ammonium citrate to lose an electron, making them more unstable and reactive toward the ferricyanide. This reaction yields a dye known as Prussian blue that saturates the print and produces a cyan-toned image.  

Given that “photography” is now as simple as aiming your iPhone 11’s multiple cameras at an object and pressing a button, it’s refreshing to know that photographers continue to use cyanotype printing as a strategic artistic choice to elicit a specific emotional response from the viewer. And while it may have been inconvenient for Takeshi to enlist a chemist to assist in producing pieces for his exhibition, we agreed that the experience was very valuable because we both came to learn about and appreciate the other’s area of expertise. Cyanotype creates stunning images and opportunities for collaboration between artists and scientists—there’s no need to be blue!

Researchers optimized a reaction involving DEAD to reduce chemical waste

The Mitsunobu reaction is key to using alcohols in organic chemistry, but it also generates considerable chemical waste

Teresa Ambrosio


University of Nottingham

Alcohols are heavily used in organic chemistry because they are cheap and widely available. However, they are also quite stable and react slowly. Before their use, alcohols require a pre-activation step, and one of the most common ways to do it is the Mitsunobu reaction

This reaction involves the use of the chemical diethyl azodicarboxylate, which is known as DEAD in the chemistry community for its high toxicity. DEAD is used in a stoichiometric amount (i.e. a one-to-one ratio) with respect to the alcohol in this reaction. This means that if we want to modify 1,000 units of alcohol, we need 1,000 units of DEAD, which will consequently produce 1,000 units of chemical waste. This major drawback prevents the implementation of the Mitsunobu reaction on a larger industrial scale, especially in uses such as the production of drug candidates.

Recently, researchers at the University of Nottingham have managed to design and optimize a new way of carrying out the Mitsunobu reaction through the use of an organocatalyst. Here, an organocatalyst refers to an organic compound which can speed up a chemical reaction, but isn't consumed by the reaction. Specifically, the researchers designed a phosphine oxide compound to optimize the Mitsunobu reaction. 

The way this newly optimized reaction works is the following: the alcohol is bound to the organocatalyst, which leads to the formation of "activated" alcohol. Once the alcohol is activated, it reacts much more quickly with a nucleophile (i.e. a chemical species which donates electrons), leading to the formation of the desired product and returns the organocatalyst to its original state. In this state, the organocatalyst can bind to a new unit of alcohol and repeats the reaction. This cycle keeps on repeating until all the alcohol units undergo activation and are used up.

Replacing DEAD with an organocatalyst not only has the advantages of removing a highly toxic and dangerous chemical compound, but also forms water as the only side-product. This newly optimized reaction was used to produce thiocarlide, a drug used to treat tuberculosis, which highlights the potential of this newly optimized reaction and its promising application on an industrial scale.

Fires explode across Australia as the continent records its first-ever day without rain

And they are predicted to get worse as the dry weather persists

Olivia Box

Natural Resources and Forest Ecology

University of Vermont

Earlier this week, no rain fell anywhere in Australia for a full day. This was the first time in recorded history that no location on the continent received a drop of rain — and as a result, the wildfire situation, already dire, is growing still more severe.

While the IPCC has stated that we have 12 years to reduce carbon emissions substantially enough to mitigate the worst effects of climate change, in some ways the crisis is already here. In  Australia, the dryness and hot air combined have raised fire warnings to "catastrophic". As of November 11th, there were over 80 fires raging across Australian states, and the number has climbed since then. A state of emergency has been declared in New South Wales, Australia's most populated state. As of now, at least four people have died and countless property damage has occurred, with the fire season projected to become even worse as the Australian summer arrives.

A tracker is keeping tabs on the Trump administration's assault on science

The Silencing Science Tracker has been compiling records since 2018

It's difficult to remember all the ways the Trump presidency has ignored, subverted, or  kneecapped science in the United States. Picking a story that best exemplifies the administration's hostility towards evidence-based policy is like picking the perfect rock to smash your own head against. 

There's the eviction of two US Department of Agriculture (USDA) research agencies from DC to Missouri, effectively firing career scientists who weren't willing to pick up their lives and move. There's the move to allow slaughterhouses to self-regulate themselves. And of course there have been countless ways that the administration has undermined the Environmental Protection Agency (EPA). This week the EPA announced its plan to relax coal industry regulations around waste disposal, which were put in place to prevent metal contamination in water supplies. Also this week the EPA announced new policies that would restrict what research could be used to base policy on. It's too much to keep track of.

Luckily you don't have to. The Silencing Science Tracker has been keeping diligent records on the Trump administration's behavior around science for almost two years. The tracker lists every instance of distorting science that's occurred at the federal and state level in the US since January 2018, founded on the one year anniversary of Donald Trump's inauguration. I spoke with Susan Rosenthal at the Sabin Center for Climate Change Law and Climate Science Legal Defense Fund at Columbia University, which houses the Tracker:

"[We're] seeing all these things, a lot of stuff about web pages being removed, and [scientists] were being asked to or were choosing to censor their work, to stop using certain words, from this fear of attracting attention from officials that were appointed by the new administration." 

The Tracker only deals with absolute, concrete stuff. So even though the westward movement of USDA and Bureau of Land Management scientists out of DC has a strong air of suppression, since there's no hard evidence that the move was an act of repression, it's left out. 

You can sort by state, agency, explanation given, and even by scientists affected. The amount of climate science being ignored or interfered with is so great that the scientists affected are simply categorized as "Climate," with 261 entries, or 201 "Other" entries. The depth and breadth of climate science suppression is breathtaking. Even Amtrak of all agencies has deleted references of climate change from reports, and withheld studies on the effects of climate change. Said Rosenthal:

"We have a lot of stuff to add, which is good for the Tracker, but obviously, is bad."

Science articles written by scientists perform as well as those written by journalists

Scientists are helping to fill a critical void and bringing unique perspectives to science communication

Amy R Nippert


University of Minnesota

Can scientists fill the void in science journalism? A new study posted on bioRxiv asked this exact question, and found that in terms of article engagement, scientists and journalists engage audiences at roughly equivalent rates. The researchers, led by PhD student Yael Baren-Ben David from the Technion-Israel Institute of Technology, looked at views, clicks, comments and time spent on the page as metrics of engagement, and compared equivalent articles written by scientists and professional journalists. For the two major Israeli online news sites that they studied, the audiences literally and figuratively “liked”  articles equivalently no matter who wrote them. 

As the number of professional science journalists has declined, scientists have fulfilled the important task of communicating science to the public. As a scientist writing for Massive, it’s reassuring to me to see data confirming that scientists can write in a way that engages the general public, and that the public responds positively. 

The study authors note that while scientists can inform and share science news, they are not independent outsiders and have other limitations on their time and knowledge. Increasing the number of scientists writing articles may accelerate the decline of science journalists, and increase reliance on unpaid, outside sources. Despite these caveats, scientists can still play an important role in science communication. It only benefits society to hear their unique points of view.

Snails are turning yellow to adapt to climate change

Science-loving citizens helped researchers look at how urban environments affect snails

Sruthi Sanjeev Balakrishnan

Cell Biology

National Centre for Biological Sciences

Simply owning a smartphone takes you one step closer to becoming a scientist. They're sometimes the instrument of choice for evolutionary biologists. By submitting pictures of snails through an app, science-loving citizens helped researchers look at how urban environments affect snails.

Human activity makes cities warmer than their surroundings. Snails are sensitive to such temperature changes, so having paler shells keeps them cool by reflecting sunlight. The snails studied here, Cepaea nemoralis i.e. a grove snail, can have pink, yellow or brown shells, with up to five dark stripes on them. They are also found both in cities and forests. If shell patterns are actually adaptations to different temperatures, are there more light-patterned snails in cities?

Grove snail - yellow outer shell - bark, tree, nature

 The grove snail or brown-lipped snail (Cepaea nemoralis) on a branch.

By Mad Max 

Menno Schilthuizen’s research group at Leiden University tried to answer this question by studying snail pictures from across the Netherlands. Schilthuizen’s lab built an app  — SnailSnap  — that could be downloaded by anyone with a smartphone. The app had instructions on the kind of snails to take pictures of, which were uploaded to a server and analyzed by an algorithm.

The algorithm classified pictures in three ways: shell color, number of stripes, and environment. After sorting through nearly 8,000 images, it showed that yellow shells were more common in urban areas. This made sense as yellow reflects more sunlight than other colors. 

Strangely, it was not snails with the least number of stripes, but ones with an intermediate number that were more populous in cities. This observation directly clashed with the “lighter is better” notion, as stripes are dark bands and having them reduces the shell’s capacity to reflect light. The researchers think they may have stumbled upon a novel way of regulating temperatures, where the snails use a combination of light and dark patterns to adjust heat radiation. 

The scientists now plan to expand their project and analyze feather patterns in urban birds, once again enlisting the help of citizens in research. So next time you snap a picture of a pigeon, consider turning it in to these Dutch scientists.

We need to talk about our current global antimicrobial resistance crisis — in a more effective manner

Antimicrobial resistance has been declared a global health threat, but we're running into barriers when it comes to communication

Luyi Cheng

Molecular Biology and Structural Biology

Northwestern University

Antimicrobial resistance has been declared a global health threat by the World Health Organization and a quick Google search can easily lead you to many other reports and awareness efforts. These resources, in addition to explaining the current issue of antimicrobial resistance, also detail methods to manage and prevent the further spread of drug-resistant microorganisms. But all of this evidence will remain hidden — unless we effectively communicate the contents of these reports to achieve widespread public understanding and support.

Recently, to fill this gap, the Wellcome Trust released a report on how to communicate about antimicrobial resistance.

The report first summarizes current barriers to successful communication. These barriers include how we use multiple terms for antimicrobial resistance (for example antimicrobial versus antibiotic), which doesn’t help to connect different messages into one unifying issue. Media coverage often focuses on specific outbreaks, which also makes it hard for audiences to connect broad causes to resulting events.

In response, the report recommends five principles for effectively communicating about microbial resistance, based on desk research, media analysis, interviews, and public message testing. One suggestion is to frame antimicrobial medicine as undermining all of modern medicine and negatively affecting treatment across several diseases, rather than treating it as a singular health issue, like tuberculosis or MRSA. Additionally, using ‘apocalyptic’ messaging can lack credibility and lead to skepticism with audiences. Instead, the report suggests showing that antimicrobial resistance is not only an issue we are facing in the upcoming future but as an everyday issue in our lives right now. Usng this messaging encourages immediate action.

To me, this report is valuable for addressing the particular global issue of antimicrobial resistance and also more. It is part of a growing body evidence-backed resources for communicating current scientific issues that is incredibly valuable for bridging gaps in sharing knowledge in our communities. 

Catch Mercury crossing in front of the Sun, or wait 'til 2032 for your next chance

From about 7:35AM to 1PM EST, a tiny dot will chug across the Sun

Every year there are special astronomical events. This one only happens a handful of times a century. A tiny, tiny, small, smol dot, the planet Mercury, will transit across the Sun the morning of November 11th, like an eclipse in miniature. Look up (with proper eye protection), or wait until 2032 for your next chance to see it. The picture above is of the last transit in 2016 (here's a fun, dramatically-scored video of it, just for fun). 

Check out more info from NASA Jet Propulsion Lab here.

By tracking star "pollution," scientists have found exoplanets similar to Earth's structure

Using oxygen pressure as a measure, scientists examined the structural properties of white dwarfs

Rebecca Dzombak


University of Michigan

Humans have been wondering whether we truly are alone in the universe for millennia. Part of our quest to understand our place has involved searching for other planets like Earth in the Solar System and beyond — but that's much easier said than done. Space, as it turns out, is big, and other planets are far, far away. Studying them in detail, then, is tricky.

A new study in Science gets around this roadblock by studying white dwarfs, which are not an obscure fantasy reference but are actually the remnants of low and medium mass stars. By studying the "pollution" in these white dwarfs, which occurs when rocky bodies crash into the stars earlier in their lives, Doyle and colleagues were able to estimate the rocks' geochemical and geophysical properties — specifically, what was are they made of and what their structures involve.

To estimate these properties, Doyle and colleagues relied on a key geochemical indicator: oxygen fugacity, which is a measure of the partial pressure of oxygen in rocks as they form. They measured six elements as oxides, including magnesium, silicon, aluminium, calcium and iron. As these oxides must have been in thermodynamic equilibrium with oxygen during formation, their abundances can be used to estimate an overall oxidation state. That estimate can then be linked to atmospheric composition, the geochemistry of its crust and mantle, and even the size of its core.

Ultimately, Doyle and colleagues determined that these rocky exoplanets were similar to Earth and Mars in terms of both composition and structure. So there are some exoplanets like ours in the universe...and this brings us one step closer to knowing how we fit in the universe. 

Mice need microbes to forget their fears

Germ-free and antibiotic-treated mice have impaired fear extinction

Claudia Lopez-Lloreda


University of Pennsylvania

Halloween can be a fearful time for many. Ghosts, ghouls and goblins run around on Halloween night, spooking children and adults alike. But once we get used to them and realize that they do not pose a threat, the brain can get rid of, or extinguish, that fear memory. Now that it's November, you've probably forgotten all about any Halloween frights. 

Neuroscientists have long been interested in the processes that allow the brain to eliminate fear memories, since problems with "fear extinction" are linked to post-traumatic stress disorder and other anxiety disorders. Now, a new study sheds more light on how the billions of tiny microbes in the body may play an important role in getting rid of fear. 


The "microbiota" encompasses all the microorganisms that live on and in your body. The recent study looks at how getting rid of the microbiota affects fear extinction in mice. The researchers exposed mice to a tone paired with a shock, which after many exposures, leads the mice to create a "fear memory" and freeze in response to the tone. Fear extinction then happens when the mice are repeatedly exposed to the tone without the shock and eventually forget the fear memory. To examine the role the microbiota play in fear extinction, researchers treated adult mice with antibiotics to reduce their microbiota or used mice that had been microbe-free since birth. Although antibiotic-treated and microbe-free mice created a fear memory as well as the control mice, they continued freezing even during extinction, meaning they were not able to get rid of the fear memory. 

When researchers looked at the brains of the antibiotic-treated mice, they found that there were significant differences in the expression of genes and of neural activity in the cells of the medial prefrontal cortex, a brain area critical for fear extinction. Among other changes, researchers found that changing the microbiota led to alterations in microglia, the immune cells of the brain. Microglia eat up dendritic spines, which are small protrusions off of neurons that receive input from other neurons. The researchers identified that there was more spine elimination in the antibiotic-treated mice, suggesting that learning might be affected by an imbalance in spine elimination due to microglia alterations. 

When researchers analyzed the brain fluid of these mice, they found that there were four chemicals that were decreased in the microbiota-less mice. Researchers think that these chemicals might be an important way that microbes influence brain function. These findings shed new light on the ways that the microbiota can extinguish fear. 

TikToks are teaching Generation Z about science

Yes, you can share funny clips on TikTok, but what about communicating science on this platform?

Rebecca Muir


University College London

Teenagers across the world use the short video-sharing app TikTok to escape their schoolwork. Or, that's what teachers thought. Surprise! Creators on the app are now using it to teach Gen Z-ers everything science — ranging from genetics, to squid biology, and even science policy.

TikToks are easily digestible, 15 second videos which are accompanied by a song or audio-clip. The platform is geared towards entertaining middle and high schoolers. Nearly half of users are 10-20 years old, and the average user spends 53 minutes on the app every day. Scientists have spotted a niche in the TikTok market, and are starting to build science communities around the app, such as the Let’s TikTok about Science Twitter account.

What sort of videos have creators made so far? Here are a few examples.

Darrion is a Research Technician at Baylor College of Medicine, and uses a Nicki Minaj meme to explain gene expression:

Sarah McAnulty is a squid biologist and assistant research professor at the University of Connecticut, and in this video, uses Willow Smiths' dulcet tones to soundtrack a sea cucumber.

Megan McCuller specializes in non-molluscan invertebrates at a natural history museum, 1001 jars, and shows something which defies explanation.

Dr. Robert Lepenies is a research scientist in Berlin specializing in policy, environment, ethics, who wants to show other scientists what they are missing.

Reddit's r/science community is one of science writing's biggest outlets, with the stats to prove it

At ASHG 2019, Jennifer (Piper) Below shares the numbers behind r/science's global reach

Farah Qaiser

Molecular Genetics

University of Toronto

When scientists look to sharing their newly published research, they often turn to media outlets with large audiences. But at the American Society of Human Genetics (ASHG) 2019 conference in October, I realized that Reddit's r/science community is the front page we may all be missing out on.

In case you haven't already stumbled on to the site, Reddit – “read and edit” – is a news aggregation social media platform which is often referred to as the front page of the internet. It's composed of over a million subreddits (communities), where the 13-year-old r/science is “a place to share and discuss new scientific research." Fun fact: r/science has over 22.6 million subscribers, making it the fifth largest subreddit on the site.

Jennifer (Piper) Below is an Assistant Professor of at Vanderbilt University Medical Center – and is also one of the 1,500+ moderators on Reddit's r/science community. At ASHG’s communications workshop, Below shared that in September 2019 alone, the r/science community “averaged 5.6 million unique users and 29 million page views” – which happens to be a larger circulation than all top ten US newspapers' weekday circulation (including USA Today, The New York Times, and the Wall Street Journal).

At r/science, Below says that there are three goals: to normalize interactions with scientists, to illuminate the processes of science (rather than only the results) and to promote disintermediation (i.e. skipping news outlets to go straight to the scientists). Below says that r/science does this in three ways: user-submitted links to research, hosting a monthly science discussion series (replacing the old Ask-Me-Anything format) and by verifying users.

newspaper bundle


By AbsolutVision on Unsplash 

Below says that “presenting your work in an r/science discussion is likely the largest audience you will ever have in your career” and hopes that science discussions on Reddit will become a culturally expected next step for scientists once they publish an “important” paper. For example, r/science has hosted discussion series on climate change, concussion injuries right after the 2019 Super Bowl and a conversation with the research group of Frances Arnold – the 2018 Nobel Prize in Chemistry winner, where the climate change science discussion had around ten million impressions and over 183k views.

Submissions requirements and comment rules help keep r/science conversations polite and scientific. In fact, by verifying their expertise and displaying an educational flair (e.g. “Grad Student | Physics”), Below says that Reddit users can help provide the context behind research, including methodology and statistics. Of r/science's 5,000+ verified users, 31% have a Bachelor of Science degree, where an additional 4% and 24% identify as professors and graduate students. Biology (19%) is the largest verified field, followed closely by engineering (16%) and medicine (12%). Journalists, writers and university press relations can also request flairs.

Interested in exploring r/science? Below recommends creating a Reddit account – and to consider adding an educational flair to your account or hosting a discussion series. After all, if you truly want to communicate your science with the public, why not head directly to the front page of the internet?

Human disturbance is drying out forests

Thinning out the canopy impacts the water cycle within a forest, causing more moisture to be lost to the atmosphere

Rebecca Dzombak


University of Michigan

New research from northern Michigan shows that when a forest's canopy structure is disturbed — when leaves and branches thin out and provide less coverage — it's not just the view that's affected. The forest's water cycle is affected, too. 

Researchers studied two areas of the forest at the University of Michigan's Biological Station. One area had been intentionally disturbed a decade ago by killing certain species of trees to thin out the canopy. One area was an undisturbed control area. Researchers found daily and seasonal differences in the movement of water in these different areas of forest. The strongest differences in water cycling occurred during the summer when evapotranspiration rates were highest. Forest areas with more open canopies showed more mixing between the air above the forest and the air within the forest, suggesting a greater degree of connectivity between the land, forest, and atmosphere. This meant that the air within the forest was drier. Canopy structure, then, serves as a sort of regulating mechanism for moisture release to the atmosphere, with dense treetops holding moisture closer Earth's surface.

 Photo by Casey Horner on Unsplash 

Water stress is already a substantial problem in many areas of the world, and the problem is likely to get much worse in the coming decades. Since changes to canopies can be driven by both humans (forest management and logging) and climate change (ecological succession), is it important to understand how changes in the canopy structure impact the water cycle in a forest, and, in turn, how this affects regional water stress.

Kristen Vogt Veggeberg

Science Education

University of Illinois at Chicago

Ed: All this week Massive is marking Halloween with stories of scary, witchy, and downright ghastly stories from nature

If you walk around an old cemetery, you might notice tombstones that have sunk into the dirt, tilted to the side, or even appeared to move across the ground since they (and their owners) were first placed. This is because these gravemarkers are heavy and the dirt under our feet is often unstable over long time periods. The tread marks left behind have inspired spooky urban legends.     

Unfortunately for those that love ghost stories, there’s a scientific explanation behind the phenomenon of moving tombstones. It’s  got the wonderfully spooky name of "downhill creep" (or soil creep), and also explains natural phenomena such as bending trees on a hillside or depressions in mountainsides. 

There is even a physics formula that explains downhill creep. Called diffusional sediment flux, this is calculated as the product of hill-slope and a value called the diffusion constant. Those values multiplied together yields the speed at which a given tombstone (or any physical object on a hill) moves over time. In addition to just modeling tombstone movement, this formula has also recently been used to calculate how erosion rates change with precipitation

So if we calculated this value for the average tombstone on a hill, it is pretty clear that it will always be gently moving, tombstone owner beneath be damned.  

Just in time for Halloween, the spookiest primate tricks the world with a hidden thumb

The aye-aye has been hiding a secret all this time: a sixth pseudodigit

Darcy Shapiro

Evolutionary Anthropology

Rutgers University


The aye-aye (Daubentonia madagascariensis) is an incredibly specialized primate. For one thing, it's the only living representative of its family of lemurs. It also has rodent-like ever-growing incisors and bat-like ears that it uses in combination with an extra-long third digit to tap on trees, listen for the grubs inside, and then extract them with that spindly finger. 

And these features make it look pretty creepy. So creepy, in fact, that seeing it is traditionally considered a bad omen or a direct cause of bad luck in its native country, Madagascar. 

Given the aye-aye's specialized hand anatomy, it seems like anthropologists would have already investigated that structure pretty thoroughly. But it turns out the aye-aye's hand has been hiding a secret - a sixth pseudodigit! 

An aye-aye, a strange nocturnal primate that only lives in Madagascar

Frank Vassen on Flickr

In a new study published in the American Journal of Physical Anthropology, a group of researchers investigated the hand anatomy in one immature and six adult aye-ayes using traditional dissection digital imaging techniques. Like the famous "thumb" of the giant panda, the aye-aye also has a radial sesamoid bone in its wrist that seems to help it compensate for the grasping ability the aye-aye lost when its third digit became specialized for probing out insect larva. Sesamoid bones form within tendons, typically where they cross joints, and the aye-aye's is both enlarged and has muscles attached to it to help it function like a faux-thumb. 

This is the first accessory digit found in a primate. By understanding how these different structures integrate in the aye-aye's hand, we may gain further insights into the evolutionary history of the pseudothumb - and the fascinating and endangered aye-aye species.

Climate change threatens bats⁠ — and tequila

Climate change could destroy the delicate partnership between agave plants and the bats that pollinate them

Kelly Franklin

Conservation Biology

Temple University


Changes in temperature and precipitation associated with climate change alter the habitable ranges for many species. This becomes especially problematic for species that depend on mutualisms — relationships where both species benefit — for existence. Not only are plant-pollinator mutualisms vital for survival of the species involved, they also provide us with numerous economic and cultural services to boot. 

We often hear about how climate change threatens bees, our most iconic pollinators, but rarely do we think about the pollinators of the night — bats. Mexican long-nosed bats pollinate the agave plant during their migration from central Mexico to the Southwestern United States every spring — following the blooms of their primary food source. By pollinating the agave, these bats provide us with sweeteners, biofuels, building materials, and most notably tequila

Photo by Francisco Galarza on Unsplash

Mexican long-nosed bats are currently listed on IUCN Red List as endangered due to habitat loss, agricultural practices, and human disturbance. But a recent study published in Scientific Reports shows that climate change also poses a threat to the already perilous existence of the Mexican long-nosed bat. Researchers found that climate change is poised to reduce the overlap in the suitable range of the agave and the Mexican long-nosed bat by at least 75%, putting this already fragile partnership at risk of disappearance.  

As the range for the agave plant shifts to higher elevations and cooler temperatures, this primary food source sustaining the bats during migration will vanish from their route. Maintaining the bats’ migration corridor is key to the preservation of both the partnership between these species and the species themselves; for the tequila and bat lovers out there, it’s non-negotiable.

Neurotoxins in the water supply worsen the impact of Zika virus

A neurotoxin produced by cyanobacteria may help explain patterns of Zika-associated microcephaly in Brazil

Zika virus is transmitted by Aedes aegypti — a mosquito that also transmits dengue and yellow fever. In some people, the virus causes symptoms that are very mild. Other cases, however, are dramatic — fetuses that are infected inside the womb can develop microcephaly, a condition in which the baby's head is much smaller than expected. Unfortunately, many cases were reported in Brazil during the recent outbreak of the disease.

The situation motivated Brazilian researchers to search for answers. Some were found quickly: in 2016, a paper described how the virus affects the development of brain organoids. But a big question remained unsolved: why were the microcephaly cases concentrated in northeast Brazil when Zika was spread throughout the country?

Various hypotheses were on the table: folic acid deficiency in pregnant women in northeastern Brazil, coinfection with other mosquito-transmitted viruses, extreme poverty, or even the use of pesticides in agriculture. But nothing seemed to explain why there were so many cases of microcephaly in this particular region.

An interdisciplinary team lead by neuroscientist Stevens Rehen, from the Federal University of Rio de Janeiro, recently published a preprint that adds one more piece to that puzzle. The group investigated how environmental factors can influence the development of microcephaly.

Northeastern Brazil suffers from drought periods, which can lead to blooms of cyanobacteria. Those microorganisms often produce toxins that can be harmful to human and animal health.

Cyanobacteria bloom

NASA Goddard Space Flight Center

The new hypothesis to explain the microcephaly boom in northeast Brazil involved saxitoxin, a neurotoxin produced by the freshwater cyanobacteria Raphidiopsis raciborskii. Perhaps because of a severe drought in the region from 2012 to 2016, there was a higher saxitoxin occurrence in the drinking water supply of northeast Brazil compared to the rest of the country.

In the lab, the team showed that the presence of saxitoxin doubled the cell death rates in progenitor areas of human brain organoids infected by Zika virus. Scientists now believe that this might explain why microcephaly was worse in the northeast region.

Due to the complexity of the Zika outbreak in Brazil, the scientific community had to exercise true detective skills. Scientists had to go beyond their own lab walls and connect different knowledge areas to solve the puzzle. Hopefully, these new findings will help to prevent future cases of Zika-associated microcephaly.

A parasitic flatworm is one of nature's spookiest creatures

Leucochloridium paradoxum is a parasitic flatworm that uses both mind control and mimicry to trick birds into eating it

Monica Javidnia


University of Rochester


Larval Leucochloridium paradoxum, more commonly known as the green-banded broodsac, is a parasitic flatworm ingested by snails feeding on bird feces. As the parasite grows, it comes to take over the snail's tentacles, leading to one to two appendages resembling wriggling caterpillars or maggots  — known as mimicry. 

Mimicry is an umbrella term used to describe when organisms look like other things. For example, insects can look like twigs or leaves to blend in with their surroundings, anglerfish attract prey by wiggling their esca (an adapted spine) to resemble a smaller fish, and some flowers are shaped like female insects to attract males for pollination. L. paradoxum takes mimicry a step further by drawing the snail out into the open to increase its chances of getting gobbled up by a bird.

Land snail Succinea putris with Leucochloridium paradoxum inside its left eye stalk

A land snail with Leucochloridium paradoxum inside its left eye stalk.

By Thomas Hahmann.

Researchers have also found snails infected by L. paradoxum tend to stay in open, better-lit places and on higher vegetation, making them an irresistible snack for birds. Once in the bird, the parasites continue their life cycle, turning into adults, reproducing, and laying eggs. These eggs are released through bird droppings, and the cycle continues!

But the green-banded broodsac is not the only parasite that uses sinister mind control or mimicry to make its way through life. Toxoplasma gondii causes behavioral changes in mice to make cats eat them, and Myrmeconema neotropicum infects worker ants, causing a berry-like blob that will attract birds. 

The worst mimicry of all? Raisin cookies that trick me into thinking they're chocolate chip.

Ed again: The views shared by the author in this article do not reflect the cookie-related positions of Massive. We support oatmeal raisin cookies.

Have you ever wondered why it's harder to maintain your weight as you get older?

New research shows that as you age, the rate at which lipids are removed from your fat tissue decreases

Daniela Helena


Università della Svizzera Italiana

Have you ever wondered why athletes often cannot maintain their weight as they get older? Could the culprit be their newly discovered passion for binge-watching while eating fast food? Or could it be that they changed…nothing at all? Interestingly, new research shows that as you get older, the rate at which lipids are removed from your fat tissue decreases, which may explain why maintaining weight is harder as you grow older. 

Our white adipose tissue, the main fat-storing tissue in human adults, is one of the main targets when tackling obesity or weight changes. Its size is determined by a phenomenon called lipid turnover – the balance between how much energy your body stores as fat and how much it burns of the stored fat.

food salad chocolate diet

This means that, as you age, if you keep that exact same (now not-so-perfect) diet, your lipid uptake will get higher than your lipid removal and you will gain weight. 

By Brenda Godinez on Unsplash 

Imagine you have a high lipid turnover. Then, the average time lipids spend in your adipose tissue is low. Now imagine you have matched that with the perfect diet. As long as your lipid turnover doesn’t change, your weight will stay the same. The caveat comes with your ever increasing age.

The researchers had been following adults for up to 16 years and continued to measure the lipid turnover of their subcutaneous fat. They discovered that, irrespective of long-term changes in body weight, initial age or even level of exercise, the rate of lipid removal from their fatty tissue was decreasing with age. This means that, as you age, if you keep that exact same (now not-so-perfect) diet, your lipid uptake will get higher than your lipid removal and you will gain weight. In fact, participants who didn’t change their diet during the study period saw their weight increase.

How can you cope with this? To put it simply, the fat that gets stored in your body mainly reflects the amount of food you eat (and not only extra fat, but also extra sugar, gets stored as fat!). Although other factors, such as exercise or the composition of your diet, may eventually also influence fat deposition, this will not alter your rate of lipid removal. So, until other therapeutic approaches come out, we may have to accept that, as we age, we may need to lighten our diets if we want to avoid those extra pounds.

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