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Rama via Wikimedia Commons // CC BY-SA 2.0

Mouse Gut Microbes May Be Messing With Study Results

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Rama via Wikimedia Commons // CC BY-SA 2.0

Microbiota—the ecosystems of bacteria, fungi, and other microbes in humans’ and other animals’ guts, genitals, mouths, and elsewhere—are astoundingly powerful organisms. They can make us sick or help keep us well. They can even influence our behavior. And now, scientists are realizing, they’re probably altering the outcomes of our experiments.

In recent years, the scientific community has wrestled with what some have called a “crisis of reproducibility”—the realization that the bulk of published experiments cannot be successfully replicated by other researchers. One of the most likely culprits is human error, or, more specifically, the very human inability to notice and consider variables that could affect an experiment’s results. And when it comes to animal studies, there are a lot of variables to consider. One experiment found that a parasite changed a commonly studied behavior in zebrafish, while another noted that uncomfortable temperatures in the lab can make mice more susceptible to cancer. Now the rodents’ belly bacteria are under the microscope.

Because as powerful as our microbes are, they’re also incredibly sensitive. Studies have shown that the communities in our bodies can be affected by the company we keep, whether or not we use deodorant, and even by what our grandparents ate. They’re essentially a variable stuffed with other variables. And when they change, so do we.

Michigan State University physiology researcher Laura McCabe learned this firsthand when she decided to repeat one of her own successful mouse experiments. “I was thinking, ‘Hey, great! Let’s repeat it one more time to be certain,’” McCabe told Kelly Servick in Science. But she couldn’t. McCabe and her team tried to reproduce their results in a new set of mice, to no avail. They tried a second time and failed again. At a loss, they decided to take a look at the rodents’ gut bacteria. They took poop samples from the control groups of all three experiments. There, under the microscope, they saw the difference: Tthe three groups had very different microbiota even before the experiments began.

McCabe and her colleagues are in good company. Last year, experts at the National Institutes of Health’s Mutant Mouse Resource and Research Center (MMRRC) set out to determine what a healthy, normal mouse microbiome looked like. They took poop samples from mice from two major scientific mouse suppliers, looking for a consensus. They found some overlap, but also some significant differences. One vendor’s mice were missing important immune-boosting microbes called segmented filamentous bacteria. Without them, the mice were more likely to fall ill.

Today, researchers concerned with matching their mouse guts can send samples of their mouse poop to the MMRRC for analysis. Some scientists predict that within the next two decades, published papers will have to include microbiome analysis. Until then, it’s up to researchers to keep track of the little things.

[h/t Science]

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Land Cover CCI, ESA
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European Space Agency Releases First High-Res Land Cover Map of Africa
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Land Cover CCI, ESA

This isn’t just any image of Africa. It represents the first of its kind: a high-resolution map of the different types of land cover that are found on the continent, released by The European Space Agency, as Travel + Leisure reports.

Land cover maps depict the different physical materials that cover the Earth, whether that material is vegetation, wetlands, concrete, or sand. They can be used to track the growth of cities, assess flooding, keep tabs on environmental issues like deforestation or desertification, and more.

The newly released land cover map of Africa shows the continent at an extremely detailed resolution. Each pixel represents just 65.6 feet (20 meters) on the ground. It’s designed to help researchers model the extent of climate change across Africa, study biodiversity and natural resources, and see how land use is changing, among other applications.

Developed as part of the Climate Change Initiative (CCI) Land Cover project, the space agency gathered a full year’s worth of data from its Sentinel-2A satellite to create the map. In total, the image is made from 90 terabytes of data—180,000 images—taken between December 2015 and December 2016.

The map is so large and detailed that the space agency created its own online viewer for it. You can dive further into the image here.

And keep watch: A better map might be close at hand. In March, the ESA launched the Sentinal-2B satellite, which it says will make a global map at a 32.8 feet-per-pixel (10 meters) resolution possible.

[h/t Travel + Leisure]

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iStock
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Scientists May Have Found the Real Cause of Dyslexia—And a Way to Treat It
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iStock

Dyslexia is often described as trying to read letters as they jump around the page. Because of its connections to reading difficulties and trouble in school, the condition is often blamed on the brain. But according to a new study published in Proceedings of the Royal Society B, the so-called learning disability may actually start in the eyes.

As The Guardian reports, a team of French scientists say they've discovered a key physiological difference between the eyes of those with dyslexia and those without it. Our eyes have tiny light-receptor cells called rods and cones. The center of a region called the fovea is dominated by cones, which are also responsible for color perception.

Just as most of us have a dominant hand, most have a dominant eye too, which has more neural connections to the brain. The study of 60 people, divided evenly between those with dyslexia and those without, found that in the eyes of non-dyslexic people, the arrangement of the cones is asymmetrical: The dominant eye has a round, cone-free hole, while the other eye has an unevenly shaped hole. However, in people with dyslexia, both eyes have the same round hole. So when they're looking at something in front of them, such as a page in a book, their eyes perceive exact mirror images, which end up fighting for visual domination in the brain. This could explain why it's sometimes impossible for a dyslexic person to distinguish a "b" from a "d" or an "E" from a "3".

These results challenge previous research that connects dyslexia to cognitive abilities. In a study published earlier this year, people with the condition were found to have a harder time remembering musical notes, faces, and spoken words. In light of the new findings, it's unclear whether this is at the root of dyslexia or if growing up with vision-related reading difficulties affects brain plasticity.

If dyslexia does come down to some misarranged light-receptors in the eye, diagnosing the disorder could be as simple as giving an eye exam. The explanation could also make it easy to treat without invasive surgery. In the study, the authors describe using an LED lamp that blinks faster than the human eye can perceive to "cancel out" one of the mirror images perceived by dyslexic readers, leaving only one true image. The volunteers who read with it called it a "magic lamp." The researchers hope to further experiment with it to see see if it's a viable treatment option for the millions of people living with dyslexia.

[h/t The Guardian]

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