On October 12th, 2017 we learned about

Probing the power of young pigs’ brains

Winnie the Pooh‘s Piglet, between hiding from heffalumps and worrying of woozles, never seems especially bright. Wilbur is reputed to be “some pig,” in Charlotte’s Web, although it’s clear that he’s not exactly the brains behind his rise to fame. On the other hand, Napoleon and Snowball are clever enough manipulate their peers to claim political power in Animal Farm. Looking outside fiction, farmers often consider pigs to be at least as intelligent as a smart dog, but usually in anecdotes instead of consistent signs of cognition. With all these mixed opinions, researchers have been taking steps to try to get a better sense of just how clever pigs really are.

Keeping track of new toys

Starting small, a study tested piglets’ memories and understanding of novelty by seeing how they responded to toys. It had previously been established that piglets did prefer novelty in the form of new toys over old ones, but this experiment wanted to establish what age piglet brains became capable of really judging what was new and what wasn’t. At four weeks old, piglets, especially female piglets, could consistently notice which toys were new to them, and which toys they’d seen two days earlier. Younger piglets wanted novelty too, but at three weeks could be fooled into thinking an familiar toy was new if it was simply presented to the piglet in a new location. Overall, this behavior puts these three- to four-week-old piglets on par with a three- to four-month-old human.

Kunekune pigs closely watch their kin

A study of Kunekune piglets in New Zealand was a bit more demanding of its test subjects. Instead of looking at how well piglets responded to novel stimuli, these piglets were tasked with observing their mother’s behavior, then applying it to their own experiences later on. While many animals can learn to imitate the behavior of their peers, observing then reproducing specific problem solving is a less common feat. In this case, piglets watched their mother or aunts through a partition as the older animal worked on getting food out of a puzzle box that required multiple, specific steps to open.

The piglets that watched an adult did seem to pick up a few pointers. They didn’t mirror the behavior they’d observed perfectly, usually changing the position the adopted for one of the required steps while still achieving the same overall motion. This indicates that they understood the task’s goal and what their motions would do to achieve it, rather than simply reproducing their mother’s actions by rote. Piglets in the control group that didn’t observe an adult took longer to figure the boxes out, as one might expect. However, once they’d invented their own technique, they were able to remember and reproduce their solution up to six months later.

Researchers suspect that the Kunekune pigs may be unusual amongst their porcine kin. The pigs are raised in family groups with space to roam and explore. This seems to provide a more challenging, enriching environment that stimulates social learning and problem solving in a way other pigs miss out on.

Source: Kune Kune Piglets Possess Social Learning Skills And Have An Astonishingly Good Memory, University of Veterinary Medicine, Vienna

On October 12th, 2017 we learned about

Materials and methods that can make a building a bit more fire-proof

With wildfires destroying over 3,500 structures across northern California in the last week, it’s understandable that my kids are feeling concerned about the safety of our own home. Aside from the smoke, we’re well out of harms way, but that hasn’t stopped some age-appropriate brainstorming about fire safety. Maybe force-fields would help? How about everyone using their garden hoses to spray the fires? Why can’t houses just be fire-proof?

Fire-proof, in the 3rd-grade understanding of the term, probably isn’t possible, but houses can be made to be very fire-resistant. Depending on the materials and design of a building, it may be able to withstand up to four hours of intense flames, and even then structural problems might come up before the whole thing actually burns. Basically, the key is to build in materials that can absorb and withstand heat while remaining chemically inert— ie., not actually combusting themselves. From that perspective, the wood frames that hold up so many American homes are sort of a terrible idea, as the wood will both burn and transmit heat to other parts of the structure. Moving away from the idea of a rustic log cabin, we should really all be living in homes made of concrete.

Preventing conflagration with concrete

Concrete frames and walls provide a number of advantages over wood. The limestone, clay and gypsum that go into concrete are very stable, and thus unlikely to react with oxygen and heat during a fire. Instead, a concrete slab can absorb a lot of heat, trapping some of it in internal pockets and pores. This can help isolate the heat from a fire, as well as insulate the building from unpleasant hot and cold temperatures in less dire circumstances. If you want to maximize the impact of your concrete walls, you probably want to install them as insulated concrete forms (ICFs), which are modular systems to further compartmentalize your concrete slabs, keeping the buildup of heat from a fire as isolated as possible.

If a building isn’t concrete, there are other options to up its fire-resistance. Bricks, having been created in kilns, hold up to heat quite well. In a fire, they can absorb heat without being damaged, with the point of failure usually being the mortar that holds a wall together. Gypsum board used in drywall can absorb a fair amount of heat without burning as well, with Type X gypsum boards being packed with calcium sulfate and water vapor inside. When exposed to fire, the water vapor can help suck up a lot of heat before the gypsum has to get cooked too much, all of which will hopefully provide time for the fire to be dealt with. On the outside of your building, common stucco usually has cement, sand and lime as ingredients, which again are inert enough to absorb heat without burning themselves.

Bad and best practices

Even with concrete or brick walls, many buildings still have weaknesses that can make them susceptible to fires. Vinyl siding and framing around windows melts pretty easily, exposing any wood framing underneath. Single pane windows that get broken allow both heat and oxygen to pass into or out of a burning building. If the source of flames is from an external wildfire, roofs are often a point of combustion. Loose shingles or semi-open tile work, can provide openings burning embers to get into a house’s attic. Overhangs are another place where fire-resistant materials are likely to be joined to more combustible wood, exposing the roof to danger even if the walls are otherwise unscathed.

So what should my kids’ theoretical fire-proof house look like then? Starting with the yard, no trees or brush should be too close to the house itself. Instead of a wooden deck, a stone or concrete patio would act as a firebreak, protecting the concrete walls. Tempered glass windows, or maybe glass bricks with an internal wire matrix to avoid cracking, would be further protected by roll-down metal fire doors that could deploy automatically in response to extreme heat. A steeply pitched roof would encourage burning embers to fall to the ground, rather than sitting and burning on the building. Internal walls would be brick or concrete, maybe with gypsum boards if you needed a softer material for some surfaces. It might start to feel a little bit like a fortress, as long as no lava (“Or asteroids!” “Or monsters!”) show up, it should be one of the cozier places to be after a wildfire.

Source: Why is concrete fire resistant? by Colleen Cancio, How Stuff Works

On October 11th, 2017 we learned about

Three repulsive reasons to keep houseflies from coming in contact with your food

So you probably weren’t about to invite a fly to land on your food, or even your body, but were you sure about why you had that instinct? Sure, it’s a good rule to not want any creature to sit in the food you’re about to eat, but houseflies quite literally bring a few extra-gross features to the table. Amazingly, the most concerning of a housefly’s activity isn’t their vomit or possibly even their feces, because the nastiest stuff tends to be stuck to their feet.

Puking on your food

Houseflies (Musca domestica), like other insects, can’t chew like you can. Like tiny, more irritating babies, they need their food to be soft and mushy, but without teeth or even jaws they have to liquefy things chemically instead of mechanically. To soften up a blob of food, they barf up a droplet of “regurgitate,” which is basically digestive enzymes that less revolting creatures would keep inside their bodies, or at least some kind of stabby mouth part. Housefly mouths are only good for lapping and sponging up liquids, so they either leave a bit of enzyme hanging off their tongue to help get at softer food, or spew a bigger dose on food that needs more time to break down.

Pooping on your food

Once the food is soft enough, the fly can then lap it up where it will be further digested in the insect’s midgut. Fly digestion, like yours, produces waste, and flies are likely to poop once they’ve gotten stripped their liquefied meals of their nutritional value. This does not mean, however, that they poop every time they land. They poop frequently enough to create what can look like splatter patterns if you know what to look for, but they’re not defecating every time they touch down on you or your food.

Pathogens on your food

As icky as vomit and feces may be, they’re not the most concerning part of a fly landing on your food. Fly feet and bodies are actually much more likely to carry and spread pathogens like, including bacteria that can cause cholera, dysentery and typhoid. A brief touchdown probably isn’t a huge reason to worry, as not enough bacteria will be transferred to necessarily kick off an infection. However, if a fly has had time to really wander around on your dinner, you might want to eat something else, especially if you’re in the countryside.

The reason locales matter is they can influence just how dirty a fly’s feet are likely to be. Flies love things like feces, decaying corpses and rotting vegetable matter, as they provide both food and places to lay eggs. Contact with these items is where the flies pick up bacteria that they can carry back to you, and in general flies in urban areas have fewer encounters with dead animals and feces, unless your neighbor can’t pick up after their dog. You’ve probably seen a fly vigorously cleaning its eyes, wings and body, but until you can get them to use soapy water, that cleaning won’t eliminate the pathogens that you don’t want to eat.

Source: Cough it Up – Fly Vomit by Nancy Miorelli, Ask an Entomologist

On October 11th, 2017 we learned about

What makes smoke from wildfires so bad to breathe in?

My neighborhood, while thankfully a safe distance from being actually immolated in the fires spread across northern California, is starting to look a little scary. The skies are darkened with the red tint of smoke, and trees just two blocks away are starting to be obscured by the thickening particulate. My third grader is… not taking it well. She’s nervously asking how close we are to the fires, if her aunt further north is safe, and if she should start expecting ash to start falling out of the sky, a scenario she only knows from stories about when a baby in southern California. Parental instinct leads me to try and calm her, but with at least 160,000 acres burned this week, how worried should we be about all this smoke?

Byproducts of burning plants

The smoke from forest fires has a lot of different ingredients. Trees’ and other plants’ exact combinations of cellulose, tannins, oils, waxes and more can create a wide range of chemical byproducts of a fire. Smoke from a burning forest is likely to contain carbon dioxide, carbon monoxide, water vapor, hydrocarbons, nitrogen oxides, benzene, formaldehyde, trace minerals and other particulate matter. While that may sound like a big scary list, your body can bounce back from the bigger molecules it inhales pretty well, with only temporary irritation to sensitive tissues in the eyes and respiratory tract. The items that are more worrisome are the tiny particles less than 2.5 micrometers in diameter, around 30 times thinner than a human hair. These minuscule particles can get lodged deep in your lungs, where they can cause more lasting damage to cells.

Avoiding inhalation

There are, unfortunately, a lot of health concerns with breathing in too much smoke. Older people, people with compromised hearts or lungs, and of course, growing kids, are all considered to be especially at risk when the air is too polluted. Kids with asthma are probably at the most risk, as irritation can cause their airways to close enough to completely restrict breathing, but anyone who’s lungs are either sensitive or still growing should really avoid breathing hard outdoors if at all possible. Breathing in some particulate is unavoidable— the goal is just to minimize exposure and impact.

Some folks wear dust or surgeons’ masks to try to stay safe, but most of those masks aren’t designed to block the tiny particulate that is of the most concern. Even if you do have an N-95 or P-100 respirator, it needs to fit against your face without gaps, otherwise you’ll end up sucking in particulate you were trying to filter out. Staying inside is probably a safer bet, using air conditioners to help filter the air. If that’s not an option, you may want to look for Clean Air shelters, or even climate controlled malls and businesses, as a way to avoid sucking in too much smoke.

Hazards from flaming houses

The fact that 3,500 buildings have burned down in these wildfires complicates things a bit. Houses these days are packed with a lot of plastics, which burn hot and fast, releasing more toxic and corrosive gasses like hydrogen chloride, phosgene and even hydrochloric acid. Thankfully, most of these won’t be released in high enough concentrations to affect the surrounding areas, and are more commonly issues for firefighters entering burning buildings. In those scenarios, the to big worries are carbon monoxide and cyanide, both of which are odorless, colorless and most dangerous in hot areas with restricted airflows, like a structure fire. Both chemicals restrict your body’s access and use of oxygen, and can be lethal in under ten minutes’ exposure. Again, this isn’t something you need to worry about in a smokey neighborhood downwind of a fire because concentrations each compound will probably be too low to cause that much harm, but it’s something to consider if you’re ever asked to evacuate, as staying in your home may put you and firefighters in much more risk if you need rescuing later on.

Extended influence

If all this weren’t enough, there’s a chance that wildfires are affecting you even if you can’t see the smoke. Global surveys of air quality have found that large forest fires release enough smoke to be detectable on a large scale, even beyond areas where the smoke is visible. In some cases, there are things that can be done to try to mitigate the impact of forest fires, from direct prevention to reducing carbon emissions that raise the world’s temperatures and make fires more likely in the first place.

For now, everyone’s rubbing their eyes, doing a bit more sneezing, and hoping that the fires can be contained before things get too much worse. If waiting things out feels too passive,  making donations to the people whose lives have been more directly uprooted by the fires has felt helpful as well.

Source: Wildfire Smoke: A Guide for Public Health Officials by Harriet Ammann, Robert Blaisdell, Michael Lipsett, et al., Environmental Protection Agency

On October 10th, 2017 we learned about

Isolating the impact of individual personalities on fish schooling performance

Anyone who’s worked on a group project has probably enjoyed the… complexities, shall we say, of trying to coordinate with people who aren’t in sync with the team. They’re not on the same page as everyone else, and don’t seem to care much either. When writing a report, this can feel very disruptive, but it looks like this kind of behavior may be helpful in some situations, like when a school of fish is hunting for food.

Sticking too close together

Researchers defined a few personality traits they thought might affect schooling behavior in stickleback fish. These included things like how closely one fish would want to sync its speed to its neighbor, or how often they would swim stray from the group. Once fish were sorted by these traits, they were allowed to explore an environment in more homogeneous groups, such as a group of fish that all prioritized social cohesion and synchronization.

It turned out that when every fish was prone to stick together, the school was unsurprisingly cohesive, but at a cost. With every fish happily doing their best to stay in the middle of the group, they barely went anywhere. Beyond that, they stuck together, but weren’t actually well coordinated in doing so, possibly because each individual was more interested in following each other than moving in a single direction. The test environment was seeded with food for the fish to discover, and schools composed of highly-cohesive fish simply weren’t as efficient at finding anything to eat. Schooling also provides protection from predators picking a single target to prey on, but checking on how safe this slow-moving school was wasn’t part of the experiment.

Simulating asymmetric schools

Building on these tests, researchers also ran simulations of schools composed of different personality types. They found that the introduction of a few fish that are less interested in sticking with their neighbors actually reshaped the whole group for the better. Even a couple of fish that were simply swimming a bit faster than a neighbor helped make the school more coordinated, probably by providing a course for slower swimmers to follow.

It’s probably too early to call the behavior of the faster, more exploratory fish leadership, since that would imply a lot of intent that this research wasn’t testing. However, it also shows how intent may not be strictly necessary, and that even minor variations in behavior can make a big difference in the school’s outcomes. This might not make your next group project easier, but it will likely inform our understanding of group dynamics as a whole, from flocking birds to the designs of swarming robots.

Source: Individuality Drives Collective Behavior Of Schooling Fish, Scienmag

On October 10th, 2017 we learned about

Baryons confirmed to constitute a considerable portion of the universes’ invisible material

We call it outer space, but that really paints the wrong picture of just how much stuff is really out there. Yes, the distances between objects are usually bigger than we can truly comprehend. Sure, there’s a lot of cosmic territory that look empty, neither reflecting or emitting any kind of detectable energy, from light to heat. However, the movement of the things we can see indicates that there’s a lot more matter in the universe, even it’s not directly visible. Researchers have long trusted that gravity hasn’t been fooling us, and now two teams have finally found some of that imperceptible stuff that scattered throughout space.

Deciphering the dark

When we look out at the universe with our eyes, telescopes, microwave detectors and more, we really only see about 20 percent of what we know must be out there. The 80 percent that we can’t directly observe is referred to as dark matter, since it never shows up as a source of light or other energy when we look. However, the behavior of planets and stars would only make sense if they were being influenced by the gravity of a lot unseen material. As confident as astrophysicists are about the gravitational forces that should be shaping the universe, it’s always good to try to validate one’s models, even if it’s just to confirm what was mostly already known.

Cranking up the contrast

In this case, two teams of researchers have independently imaged clouds of tiny particles called baryons. Baryons are smaller than a proton, consisting of only three quarks. That size reduces their chances of interacting with something like visible light, which is part of why we don’t see the huge swaths of them floating around space. To make things even trickier, they’re distributed in diffuse clouds between galaxies, making whatever traces they’d leave on their surroundings even harder to detect.

To make these baryon clouds more obvious, both teams used a technique which essentially upped the contrast on our readings of two galaxies that had been observed by the Planck satellite in 2015. Both groups overlaid the observed data on itself over a quarter-million times, making the clustered baryons more obvious to detection, although even then they weren’t directly visible. Instead, researchers had to rely on the Sunyaev-Zel’dovich effect, which is when light from the big bang itself is scattered by passing hot gas. So in the end, the teams were only able to see strands of scattered light connecting two galaxies, but that was enough to confirm the presence of otherwise invisible matter.

This doesn’t solve all of our dark matter mysteries, but it does account for a significant chunk of what was otherwise unconfirmed sources of gravity. There are hypothesis about what other kinds of particles are helping fill the cosmic void, but for now it’s nice knowing that we’ve been on the right track with our understanding of gravity so far, and that only half the universe’s mass can’t be explained. Yet.

Source: Half the universe’s missing matter has just been finally found by Leah Crane, New Scientist

On October 9th, 2017 we learned about

White-tailed deer’s dietary preferences inadvertently encourage invasive plant species

White-tailed deer are picky eaters, which poses bigger problems than your usual worries about dietary health. The North American ruminants now live in such dense populations that they make a big impact on whatever plants they choose to eat. Those preferences do shift seasonally, but with millions of deer now living in the United States, that basically means that almost every plant gets a turn to be over-foraged. Experiments have found a key exception to this pattern though, and it’s one conservationists wish the deer didn’t make.

Making space for the wrong species

White-tailed deer (Odocoileus virginianus) have long been known to devour whatever they can reach, but ecologists noticed a possible preference for native species of plants. To test just how choosy deer were, 23 plots of land in various white-tail habitats were fenced off so that the plants living there could be measured and compared. Some plots allowed deer to enter and eat, while others kept the deer out. Scientists were then able to quantify just how much of an impact the deer made on each plant species in a plot, revealing which plants they preferred and which they passed over.

Somewhat unsurprisingly, the deer liked what their ancestors liked. Probably thanks to a genetic predisposition for certain plants that were safe and healthy to eat, the deer ate more native plants than species that were imported or invasive. Importantly, this didn’t change the overall amount of plant growth in a plot, just the composition of those plants. So while a plot may have started out with 50 percent native plants and 50 percent invasive plants, the deer were essentially clearing out the native plants allowing the invasive species to claim the rest of the space. This isn’t just a problem for the native plant species, since the deer were inadvertently promoting the spread of plants that they don’t want to eat, possibly upending their dietary preferences in the future.

Population problems

While the white-tailed deer seem to be making bad situations worse, it’s not entirely their fault. Invasive garlic mustard (Alliaria petiolata), for example, was imported to North America by people as an herb in cooking, but now dominates eastern forests without many natural predators. The deer themselves followed a similar pattern. While they were once hunted to dangerously low levels, conservation laws have helped white-tailed deer populations rebound in the 20th century. However, the deer’s predators like wolves and bears haven’t been so lucky, leaving the deer to multiply unchecked. People now hunt and try to curb deer populations to a degree, but we’re not quite as good at managing their numbers as balanced food-web would be. Since the deer are on course to eat their favorite foods out from under themselves, it appears that the deer aren’t good at managing their populations either.

Source: Deer prefer native plants leaving lasting damage on forests by Lindsey Hadlock, Cornell University Media Relations

On October 9th, 2017 we learned about

The history of waffles, from the Stone Age to street food to your local supermarket

Humanity’s first shot at waffles was probably cooked on a rock. They weren’t a happy discovery made during a camping trip, but were probably some cutting-edge cuisine back in the Neolithic, or Stone Age over four thousand years ago. These proto-waffles certainly lacked refinements like an indented grid or maple syrup, but the core of what’s now a favorite breakfast food was still there— a cereal-based batter that was cooked not baked or fried, but seared on both sides. Like many cultural inventions, it seems safe to say that we’ve improved on this recipe over time, but clearly our ancestors knew they were on to something big, even before they could slather their dish in whipped cream and strawberries.

Once people started mastering metal in the Iron Age, rocks were traded out for metal plates, often held at the end of sticks to more easily reach into ovens. These early griddles basically sandwiched the batter as it was placed in heat, allowing it to be cooked in half the time. This concept would be picked up by the ancient Greeks, who called the resulting flat cakes obleios, or wafers. Like wafers you find in stores today, obleios weren’t especially cake-like, instead being cooked to a flatter, crispier consistency. They also flavored them as a savory food, using cheese and herbs instead of sugar and syrups. Europeans continued munching wafer-styled waffles well through the Middle Ages, with the only major innovations being to make them larger and sell them from street vendors.

Standing out with indented sqaures

The 13th century ushered in a new era of two-sided flat-cake cuisine, with waffles finally gaining their signature grid patterning, plus the name that we know today. A blacksmith enhanced the traditional iron griddle plates, hinging them together and putting in raised patterning that would increase the cakes’ surface area, allowing for more efficient heat distribution. More importantly, the indented squares that now marked waffles added a fun design element that caught people’s imaginations, earning the name wafel as a reference to a section of a bee’s honeycomb or woven webs. Other designs have been created since then, including coats of arms and even landscapes, but none are as iconic as the square pits we now associate with waffles.

Waffles’ popularity continued to grow throughout Europe. In the late 1500s, France’s King Charles IX even had to issue regulations concerning how close waffle vendors could cluster together to cut down on the number of fights in the streets. Recipes showed some divergence as well, with lower classes eating flatter, crispier waffles made from flour and water, while upper classes added more cake-like textures to their waffles with milk and eggs in the mix. This interest in softer, puffier waffles eventually grows into what we now think of as a Belgian waffle, which generally includes yeast to complete the effect. As popular as this concept seems now, it was certainly not part of the original flat cake recipe.

Sweeter, slower, faster and frozen in America

Waffles were brought to North America first with Pilgrims, and then again with Thomas Jefferson after a trip to France. Maple syrup finally found its home among the square divots in the 1800s, which alongside molasses, pushes waffles closer to the sweet side of the flavor spectrum. In 1869, Cornelius Swarthout of New York made his contribution to waffle history, patenting yet another improvement on the waffle griddle concept. Obviously the squares had to stay, but Swarthout’s design allowed waffles to be cooked over a stove top as long as the chef was willing to slow the process down, flipping the new waffle iron over to cook both sides. In a way, it was a step backwards from earlier technology that aimed to cook waffles faster, but it made waffle-cooking accessible in a new way, earning the date of the patent it’s own holiday in the form of National Waffle Day on August 24th of each year.

Waffles’ ties to technology meant that they kept changing over the 20th century. 1904 saw the invention of the waffle cone for ice cream, although considering waffles’ origins as flat, crispy wafers, you might not call this a major innovation. Alongside many other domestic objects, waffle irons were electrified in 1911, removing the need for the stove top, but often retaining the need for flipping. “Froffles” made frozen waffles available to consumers in 1953, although their egg-heavy flavor would eventually see them renamed as today’s Eggo products that are now part of a $211 million market in the United States. Finally, Americans got a proper introduction to Belgian waffles in 1964, although originally as “Brussels waffles.” Again, marketing concerns lead to a new name, and the vanilla and yeast-infused recipe was eventually circulated simply as Belgian waffles.

Blueberry, gluten-free, fried-chicken flat cakes

Today it seems that we have a huge range of waffle variations to choose from. Waffles can be found with fruit, whole wheat, chocolate, ice cream, pumpkin and of course, fried chicken. It seems that throughout this grand history, we’ve really only given up two aspects of previous waffles— the speed of cooking both sides at once, and the opportunity to buy waffles on the street from a horde of competing waferers when walking about town.

Source: Waffle History Page 1: The Origin & Evolution Of Waffles, The Nibble

On October 8th, 2017 we learned about

Sea birds’ sense of direction seems to hinge on their sense of smell

Not that we should start trusting breakfast cereal mascots all the time, but it turns out that Toucan Sam was onto something when claiming that we should “follow his nose.” It seems that while keel-billed toucans probably don’t smell much of anything with their large beaks, other birds are turning up with some considerable uses of olfactory information in their daily lives. Studying birds’ sense of smell isn’t always easy, but a recent look at Scopoli’s shearwaters suggests that these birds aren’t using their noses to find anything like Froot Loops, but instead use them to find their way back to shore when flying over the sea.

Staying oriented over the ocean

Scopoli’s shearwaters (Calonectris diomedea) resemble oversized gulls, complete with slightly hooked beaks for snatching up seafood. Their diet is largely based around grabbing squid from just under the surface of the water, but they can dive as deep as 50 feet under the water if need be. Depths aside, their foraging often covers a lot of lateral territory, with birds easily traversing over 100 miles in a single trip. A journey like that is only possible if one has confidence in their navigation, which is why researchers tracked some birds after plugging up their noses.

To test how Scolopi’s shearwaters are using smell to navigate, 32 birds were divided into three groups. The control group was left untouched, but the other two had their suspected navigation systems disrupted. In one case, that meant attaching magnets to their beak, supposedly to disrupt the birds’ sensitivity to the Earth’s magnetic field. The last group had their olfactory abilities disabled, using zinc sulfate to block smells but not airflow for breathing.

Following fragrances

The birds were electronically tracked, revealing that the zinc sulfate disrupted the birds’ sense of direction more than anything. When flying home, the aroma-blind birds still flew a straight course, but they did so along he wrong trajectory. As they continued, they never really course-corrected, making scientists suspect that they were missing the scents of odorous landmarks that they normally used as reference points. It’s suspected that these smells may originate from algae and phytoplankton under the water, but at this point we can’t be sure what the birds are smelling to make their mental maps.

Bird navigation has been the subject of a lot of research, albeit without the emphasis on odors. With many species making epic migrations, sometimes around the world, researchers have been trying to figure out what birds are using for their internal GPS systems. Despite the efforts of the Froot Loops’ marketing department, birds’ sense of smell hasn’t previously been seen as a likely navigational tool. This study suggests that, at least for some species, a lot of navigation is sensed through the nose.

Source: Experiment Shows That Birds Can Use Smell to Navigate in the Air by AFP, Seeker

On October 8th, 2017 we learned about

A dearth of debris around Pluto hopefully means less danger for New Horizons’ future fly-bys

There are times when NASA really looks forward to finding nothing. It’s not that anyone was getting tired of seeing new planets, or that a null result would somehow save anyone the trouble of writing up their findings, especially considering the fact that scientists actually wrote 38 pages about how much nothing they found in the space around Pluto. Pluto of course has a sizable moon in Charon and a thin atmosphere, but importantly, when the New Horizons flew by in 2015, the spacecraft didn’t have to worry about dodging icy debris floating near the dwarf planet.

Hunting for hazards

We’ve never seen evidence that Pluto had rings of debris, but we never really got close enough to see all that much detail in before New Horizons arrived to give us a better look at. The large gas giants in the outer solar system, like Saturn and Neptune, all have rings made of rock and ice, suggesting a lot of loose objects are either floating through space or being created near those planets. If Pluto followed this trend, it could have meant that New Horizons would have been flying into a very dangerous situation, since even a small pebble could rip through the spacecraft at the relative speed of 36 thousand miles-per-hour. Just to be on the safe side, a mission control team nicknamed the “Crow’s Nest” was tasked with examining every new view of Pluto for any flicker of light in New Horizon’s path that might lead to trouble.

While flying over Pluto, scientists noticed that something else was relatively absent. The dwarf planet didn’t have nearly the number of impact craters that you might expect for an object that size. As the spacecraft passed over Pluto, teams kept looking for signs of debris that would now be silhouetted against light from the Sun. With that search also coming up empty handed, it suggests that the outer solar system is relatively empty, or at least consolidated in a way that you don’t find around our other planets.

Scanning for MU69’s scraps

Aside from hinting at larger trends about the composition of our solar system, there are practical reasons that this is good news for New Horizons. On January 1, 2019, the spacecraft will fly by its next target, an 18-mile-long object called 2014 MU69. With the clear skies found over Pluto, NASA hopes that there won’t be much to run into as New Horizons travels deeper into the Kuiper Belt. However, there’s a chance that MU69 might be actually be two objects in a tight orbit around each other, to the point of making physical contact. With this possible source of debris drawing closer, the Crow’s Nest team is back at work, looking out for tiny hazards before they become big problems.

Source: Why it’s good news that Pluto doesn’t have rings by Lisa Grossman, Science News