On May 20th, 2018 we learned about

Personal relationships inform jackdaws’ responses to warnings about predators

From Chicken Little to The Boy Who Cried Wolf, humans have plenty of lessons about reacting to every alarming bit of news we happen to hear. Even if communal defenses against threats are effective, being completely indiscriminate about when to react to cries of alarm can be exhausting and risky in their own right. While we’ve never heard a bird’s version of Chicken Little, there is some evidence that some species have also figured out this lesson, as they seem to be selective about when they respond to threats reported by their neighbors. In particular, jackdaws (Coloeus monedula), a relative of crows, apparently care more about scolding calls from their closer kin over birds that just happen to be nearby.

A scolding call is a bit like the more common “alarm call” many birds employ to stay safe. However, while an alarm call simply tells birds within earshot that danger is afoot, usually prompting an evacuation, scolding calls are a call to arms. Instead of fleeing, jackdaws responding to such a call will engage in mobbing behavior, diving, harassing or possibly even vomiting on a predator until it is driven from the area. There’s obviously a bit more risk to engage a predator head on, which is probably why jackdaws don’t simply rush out to take on every predator a neighbor might see in the area.

Alarming audio

To test how the birds picked their battles, researchers recorded various scolding calls, then played them back to unsuspecting jackdaws. They found that the relationship between the listener and the bird sounding the alarm was key to a scolding calls’ success. Birds were very responsive to cries from their nest-mates, fairly responsive to members of the larger colony and less concerned about calls from neighboring colonies. Rooks, another species of bird often found near jackdaws, could get some of the jackdaws to respond, but they were clearly less influential than any jackdaw. The only other factor that seemed to shape responses was the sex of the warning bird– females from other colonies were somehow less persuasive than males.

Aside from highlighting the social nature of jackdaw safety measures, this research also demonstrates how well jackdaws keep track of individual relationships. Because the experiment only used audio recordings, the birds were evaluating the cries, and identities, of other birds by voice alone. So like humans, each jackdaw apparently has a distinctive enough voice to be used for quick identification, which can then inform their peers about potentially live and death situations.

Source: Angry birds: Size of jackdaw mobs depends on who calls warning, Phys.org

On May 20th, 2018 we learned about

Corn seedlings use their roots to communicate about possible competition in shared soil

While plants can’t necessarily choose where every seed will sprout, they’re not completely passive about how the interact with their environment. Aside from reacting to possible predators, plants also need ways to deal with competition from other plants. In some species, this can mean pushing resources from growing roots to growing stems and leaves faster in order to stay out of a neighbor’s shadow. Of course, reacting to competition that’s already creating a problem may not be enough, which is likely the reason some plants seem to communicate their stress to their nearby relatives.

To investigate how these kinds of warning might work, scientists planted corn, then tricked it into worrying about competition. Every day, corn seedlings growing on their own had their leaves brushed to simulate contact with a neighbor’s leaves in the breeze. This was known to spur the seedlings to grow taller faster, which was observed as predicted. Once a seedling reacted to its faked competition in this way, the plant was uprooted so a new seedling could take its place in the same soil. Even though that second plant had never been brushed, it started growing taller as if it had experienced signs of competition. Since the two seedlings had never had direct contact with each other, and control plants that were simply transplanted didn’t react this way, researchers suspect that the seedlings are communicating through the soil.

Signals in the soil

While the exact chemical mechanisms remains to be isolated, the assumption is that this system would allow a plant to warn its kin of crowded conditions. Other seedlings nearby would then start growing taller faster, presumably beating out competition from other kinds of plants nearby. It might not be a huge benefit to the initial messenger that sounded the alarm, but it would help that species outpace the competition in the long run.

If humans can isolate this mechanism, we will be able to better understand plants’ health and possibly even coach them into more advantage growth patterns. From a passive standpoint, detecting this kind of chemical communication in soil may help us diagnose stressed ecosystems. More actively, it may help farmers better understand and control the growth rates of their crops, either encouraging more competitive growth rates, or maybe slowing things down to establish stronger root structures.

Source: Plants 'talk to' each other through their roots by Hannah Devlin, The Guardian

On May 17th, 2018 we learned about

Various dimensions of how dinosaurs dealt with being too big to incubate their own eggs

Out of all the challenges a parent faces, at least we don’t have to worry about how to properly sit on our children. As mammals that gestate our young inside their mother’s endothermic bodies, humans can be pretty sure that there’s no upside to perching atop our offspring. It sounds a bit ridiculous, but even warm-blooded birds and dinosaurs had to likely grapple with how to best incubate their eggs at some point in their evolutionary history. In fact, multiple studies have been trying to figure out how and when these occasionally gigantic animals ever managed to incubate their eggs without smushing them in the process.

Rigid pelvises requiring petite eggs

A modern bird’s pelvis is flexible enough to allow the passage of a relatively large egg. This larger egg allows for incubating babies to be as large and robust as possible when the egg is first laid, giving them a bit of a head-start on their development. It also allows for a larger, stronger egg, which raises questions about avian dinosaurs long ago.

A study of various species’ fossils found that ancient pelvis bones were fused together more tightly than their younger counterparts. This would limit the size of an egg that could be laid, forcing creatures like Archaeopteryx to have a much daintier clutch of eggs than more modern birds of the same size. These eggs would likely be more fragile as well, possibly to the point where the relative bulk of their mother would be dangerous. If true, this suggests that birds couldn’t really sit and warm their nests before birds’ pelvises evolved to allow for relatively larger eggs, around 100 million years ago.

Leaving space for large moms to sit

A second study looked at maternal bulk from a different angle, starting with the clutches of eggs themselves, rather than mothers’ pelvises. There’s some evidence that oviraptor dinosaurs would sit on their nests for warm or at least some kind of protection, so researchers started comparing nests to see how these creatures managed their eggs. While modern bird eggs are reliably strong enough to handle their mother’s weight, some species of oviraptor grew to be at least 3,300 pounds, heavier than any egg could be expected to handle.

Looking across eggs from multiple species of oviraptor, a general strategy started to become apparent. The ostrich-like dinosaurs arranged their eggs in a circle, with each oblong-egg arranged to “point” outwards from a central point. The eggs were fairly precisely arranged, always leaving an empty space in the center of their circle. The size of that empty space was found to be disproportionately larger in larger species of oviraptor, which researchers believe was intentional. It would have allowed a heavier mother to sit and place the bulk of her weight on the ground in the middle of her eggs, allowing the perimeter of her feathered body and arms to actually cover the eggs. Smaller species could apparently rest more directly on their clutch, as the empty space in the nest was significantly smaller, even for a smaller mother.

Bury the eggs if you’re too big

So if a larger oviraptor likely left room for her body between her eggs, how did multi-ton behemoths like Argentinosaurus deal with its eggs? There’s evidence that they employed a less attentive approach to nesting, which meant digging holes with their back legs, then burying eggs in those holes. Clutches of sauropod eggs have even been found in extended lines, meaning each egg was left to its own devices (and a bit of insulating dirt.) This may sound neglectful when compared to the efforts most modern birds put into parenting, but there are some modern birds like the malleefowl that rely on elaborate mounds of dirt to incubate eggs while the parents leave the nest behind. In those cases, it’s not even that the parent bird is too heavy to incubate a clutch of eggs. The advantage is that a parent is then left to move on and find food and more mates for the future, leaving their offspring to figure out their temperature and nutritional needs for themselves.

Source: How 3,000-Pound Dinosaurs Sat on Eggs But Didn't Crush Them by Laura Geggel, Live Science

On May 17th, 2018 we learned about

Narrowing down the reasons some people have a harder time with rules and requests

My son is currently in a difficult place, as he has decided to care deeply about being “the boss” while also being five years old. So as much as he’d like to dictate the terms of bedtime or timing of dinner, there are many moments when we can’t agree with the demands and judgments of a pre-schooler. There are signs that, as he grows older, he’s becoming a bit more understanding about when it’s appropriate to cede control to the adults around him, but there’s also a chance that he may be a naturally control-averse person. It’s a mindset that everyone’s encountered from time to time, as we all have moments where expressing defiance is somehow more important than solving the problem at hand, and yet we don’t really know much about how it manifests in our brains. Researchers are getting closer, but pinning down what makes some people have a harder time following “the rules” is proving to be a difficult task.

When being asked for something backfires

If you ask people to share their thoughts on freedom, rules and autonomy, you won’t actually get very far. Most of us, from age five to age fifty, generally feel like making our own choices is a pretty good idea, even if we don’t back those opinions up in our behavior. To come up with a more objective definition of control-averse behavior, researchers had volunteers play a money-trading game in an fMRI, observing brain activity while also looking for patterns in the way people conducted themselves when they weren’t explicitly thinking about if they were “the boss” or not.

Most participants were fairly generous with their partner when playing the game. Likewise, most participants didn’t like their generosity being questioned. During some rounds of “trading,” people’s partners would request a minimum amount of money to be handed over. Almost every participant balked at these requests, complying but handing over less money than if they hadn’t been asked. So for example, if a test subject would have normally shared $15, a request for $10 would spur the subject to share less, maybe only giving $10 or $11 that round. The more control-averse someone was, the more they were likely to reduce their generosity. When asked further questions about their motivations, people who were more control-averse also reported that they were more bothered by the implied lack of trust in their partner’s request as well as a general distrust if they didn’t understand why their partner would ask for a minimum amount. More than ideas about freedom, it seemed that the issue was in understanding the partner’s motivations.

A confusing basis in the brain

Since these behavior patterns were operating on a spectrum, with some people having more pronounced reactions to minimum requests than others, it still wasn’t enough to really define control-aversion. Fortunately, the data from the fMRI scans of participants’ brains helped find a more tangible clue, as control-averse people also showed pronounced activity in the inferior parietal lobule and dorsolateral prefrontal cortex. Those brain regions don’t explain everything at this point, as they linked to everything from math to moral decision-making, but they at least offer a more objective metric than asking for people’s opinions. As researchers look into these particular bits of anatomy further, there’s speculation that the activity seen in this study is the result of a person coming to terms with their own motivations and outside stimuli that they perceive as being in conflict with their goals, even if they’re just a minimum request.

It’s worth noting that as much as control-aversion sounds like a negative (and feels negative when its coming from a tired five-year-old), it’s not necessarily a bad trait to have. There are times when questioning authority or dogma can provide important leadership, helping the rule-breaker and everyone around them. However, in some contexts it obviously causes problems, leading people do to the clash with rules or laws for what seems like a very unnecessary reason.

Source: Why Some People Just Can't Have a Boss: Study Reveals Brain Differences by Bahar Gholipour, Live Science

On May 15th, 2018 we learned about

Kim the regal jumping spider surpasses robotic mimics’ movement by leaps and bounds

As every Mario player knows, if you want to make a short, low jump, you just tap the A button. To get across a larger gap, you need to combine a running start with holding the A button for a longer amount of time. It’s a simple enough system, and yet it’s somehow not good enough for engineers trying to build tiny jumping robots. Real world complications, like physics and efficiency, pushed them to draw inspiration from some of the world’s real masters of platforming-jumping spiders.

Regal jumping spiders (Phidippus regius) are quick, tiny arachnids that can launch themselves across relatively large gaps to find safety and hunt down prey. Spiders like a regal jumping spider actually move so quickly it’s hard to tell exactly what goes into their amazing leaps, some of which can span over five-times the spider’s body length. It’s been established that spider legs move with a mix of muscle strength and changing in body fluid pressures, but to find out more researchers needed to carefully record a spider’s movement in action.

Effort and efficiency

A single spider, named Kim, was recruited to demonstrate her athletic prowess in front of a set of high-speed cameras. Kim was repeatedly prompted to jump between two adjustable platforms, almost like a gentle, tiny obstacle course. Once researchers could really see how the spider moved, they saw that Kim clearly put some thought into each jump— longer jumps were made at the most efficient angle possible, maximizing distance while minimizing effort. Shorter leaps showed an emphasis on speed, as Kim would often move in a flatter arc that would minimize distance and flight time, even if it required more of a push with her back legs to get airborne. Oddly, they also found that Kim prepped for each jump by attaching a piece of silk to the platform she was jumping off of, although researchers aren’t sure how that helped her. The silk may help provide course-correction on longer jumps, or just act as a safety harness in case the spider misses its target.

The deployed silk and distance-sensitive movements present a few challenges for engineers who would like to replicate the spiders’ jumps. While they were able to build a device that could spring across a gap, researchers concede that building in sensors, processors and other machinery to control a leap may be difficult feat in a device the size of a fingernail. They hope that some gains can be made from further study of exact mechanics of the spider’s legs. While spiders like Kim certainly use hydraulic pressure to help flex their limbs, calculations suggest that their muscles alone would be able to handle the movement observed in this study. As such, the role of the fluid pressure in each leg remains unclear. Maybe it just provides extra strength to hold the B button?

Source: Scientists train spider to jump on demand to discover secrets of animal movement by University of Manchester, Science Daily

On May 15th, 2018 we learned about

Researchers use RNA to move memories between snails’ brains

On a practical level, our brains require experience to learn and remember new information. As far as scientists can tell, that information is encoded in a network of synapses, or the connections between brain cells, in various combinations. This structural aspect of memory seems to require that brain cells construct synapses themselves, negating any chance of having new memories being imprinted or injected into the brain all at once. However, researchers are investigating other forms of information found in the brain, focusing on RNA molecules inside brain cells, instead of the connections between those cells. This has opened up some intriguing possibilities, including the ability to transfer memories from one brain to another.

Purposes beyond building proteins

RNA is a complex protein structure that plays a number of roles in cell functionality. It’s most commonly associated with transferring instructions from a cell’s DNA to actual protein production, but researchers are realizing that that is only one of its jobs in the body. To see if it can carry information about an individual animal’s experiences, researchers tried gently scaring some snails to see if RNA could hold information from a memory as well.

The experiment started with marine snails called California sea hares (Aplysia californica) which were given small electric shocks. As the research lead Prof David Glanzman, made a point to specify, the shocks weren’t strong enough to cause harm the snails, and were really only meant to get them to feel the need to retreat from a physical stimulus. After a bit of “training,” zapped snails would retreat from a gentle poke for as long as 40 seconds, while untrained snails would pull back only for a moment.

Injecting information

Once that experience-dependent behavior was established, researchers extracted RNA from brain cells of both groups of snails. The RNA was then injected into the brains of a third batch of snails who had yet to be poked one way or the other. Snails receiving “unzapped” RNA didn’t really change their behavior, reacting only briefly to gentle pokes from researchers. Snails who received RNA from a zapped snail had a bigger response, retreating from physical stimuli as if they had been trained to avoid shocks themselves. The difference in the RNA donors’ experience seemed to control how the recipient snail reacted as if they’d formed a memory on their own.

This seems like a big step towards injectable knowledge, but nobody is about to pick up a new skill in moments quite yet. Other neuroscientists point out that while this study suggests a role for RNA in memory, it doesn’t rule out the importance of synapses. Also, since snails only have 20,000 brain cells, there’s a good chance that the cognitive demand of retreating from a shock isn’t exactly on par with how our brains’ 100 billion brain cells handle new data. Still, it seems that some kind of information was shared via neurons’ RNA, demonstrating a need for further investigation.

My third-grader-asked: Did the first snail that got zapped then forget it got zapped when they took out its RNA?

This wasn’t mentioned, although memory removal would certainly be an interesting wrinkle in a world of injectable information. However, since researchers probably weren’t targeting a single brain cell in the snail’s brain, some memory of being zapped would be left behind in other copies of that RNA memory, assuming that’s how this was all working in the first place.

There also didn’t seem to be a problem with choosing which cells should recieve the RNA injection in the recipient snails, indicating that the “memory” didn’t need to be added to one cell in particular. That may be thanks to the relative simplicity of a snail brain, or that RNA memories are rather general in scope. Maybe they actually trigger physiological responses more than encode details of a specific moment in a snail’s life?

Source: 'Memory transplant' achieved in snails by Shivani Dave, BBC News

On May 13th, 2018 we learned about

Bigger relative body sizes provide a big boost to female fish’s fertility

For years, fishing regulations have demanded that anglers only keep fish over a certain size. Smaller fish were most likely younger, might not have had a chance to breed, and thus shouldn’t be removed from their ecosystem. By waiting until those fish grew bigger, they would have a chance to reproduce and keep their species’ population stable. This is a good idea, but we now know that it overlooks a very important aspect of fish reproduction– the bigger fish we were targeting are responsible for an out-sized proportion of new offspring.

This may seem like a funny concept from our perspective, since the number of offspring doesn’t really depend on a mammal mother’s size, assuming she’s healthy enough to reproduce. For at least 342 species of fish though, the mother’s size made enormous impact on how many eggs could be laid. Instead of scaling up egg production in a linear ratio to the mother’s size, larger females ramped up their egg production on a nearly exponential scale. So a two-pound fish would actually produce more than twice the number of eggs as a one-pound fish, making her size a much bigger factor in population levels. If the sheer number of eggs weren’t enough, the offspring from those eggs were often larger and more robust as well, showing that for bigger really is better when it comes to female fish.

Size but not safety

Everyone who would like to catch and eat any of these fish would generally prefer if there were more fish to catch, but the size issue complicates things. Both humans and marine mammals like orcas often target the biggest individual fish we can find since they’ll offer the most calories for a single catch. Too much of this targeting has probably contributed to fish species actually reducing their average body size, since long life spans promise less reproductive success if you’re more likely to be snatched up and eaten as a result. Compounding things further, fish gills have a harder time collecting enough oxygen as ocean temperatures rise, so climate change may be another compounding factor against any fish really reaching her full potential as a mother.

As things stand, we’re not about to solve climate change or convince orcas to give up their favorite salmon in the near future. However, we can change how humans approach fishing so that we’re not catching as many as the large female fish that enable us to keep eating seafood. Providing sanctuaries to these fish are a good start, as the fish in marine protected areas generally live longer and grow larger, giving them a better chance to spawn bigger families than we previously appreciated.

Source: The Bigger The Mother Fish, The More Babies She Has by Christopher Joyce, The Salt

On May 13th, 2018 we learned about

The Mars 2020 rover will have help scouting its surroundings from a tiny robotic helicopter

When the next rover to arrives on Mars in early 2021, it will have a sidekick along for the ride. For the first time ever, NASA will be sending a small aircraft to Mars to help scout the terrain for potential points of interest on behalf of the slower-moving rover. Consisting of a small cube, four flexible landing feet and two high-speed rotors, the device looks a bit like a remote controlled helicopter you might find at a toy store. Of course, since it will have to fly in an environment with hardly any air, there’s a bit more to this particular aircraft than anything you’d find flying around this planet.

For a helicopter to take flight, it needs a sufficient amount of air to push against in order to create lift. On Earth, those conditions exist until you reach an altitude of around 40,000 feet, at which point the atmosphere is too thin to support a helicopter’s weight. The Martian atmosphere is even thinner, approximating flying on Earth at about 100,000 feet. To get off the surface of Mars, a number of engineering feats had to be achieved, from reducing the weight of the Mars helicopter to four pounds to designing dual rotors that can spin at around 3,000 rpm. Fortunately, tests in vacuum chambers suggest that this helicopter should manage to be the first robot to lift off the surface of the Red Planet.

Sight-seeing for science

As satisfying a milestone as that represents, scientists are hoping that the Mars Helicopter will make some important contributions to the rover’s work, starting planning routes. The Curiosity rover has been working for close to six years, but has yet to travel a full 12 miles across Mars. We have spacecraft orbiting Mars, but researchers are hoping that the Helicopter can give us a more practical bird’s-eye-view of the rover’s surroundings. Even flying a few hundred feet will help mission controllers pick where to send the rover, making it’s time more efficient. This work won’t be strictly necessary, but even 30 days of modest flights would likely add to the impact of the rover’s investigations.

Since the Mars Helicopter is solar powered, there’s a chance it will be able to do more than its five scheduled test flights. Each trip will help prove that this kind of reconnaissance is viable for future missions, documenting details that may be hard to pick up from orbiting instruments like the ExoMars Orbiter or ground-based rovers and landers.

Source: Mars Helicopter to Fly on NASA's Next Red Planet Rover Mission, Jet Propulsion Laboratory News

On May 10th, 2018 we learned about

Fossilized femur suggests that spinosaurs started wading in the water early on in their family history

It’s a weird situation when half of a femur can reshape what we know about a whole family of dinosaurs. A fossilized thigh bone isn’t nearly as eye-catching as a well-preserved skull, feather imprints or mummified skin, but thanks a scarcity of fossils from spinosaur dinosaurs, even a single femur can be significant. The bone in question hasn’t even been assigned to a specific species, but its location and age are still adding to our understanding of how these semi-aquatic apex predators evolved in the Early Cretaceous Period.

Living among lakes

The as-yet-unnamed femur was found in the Araripe Basin in what is now Brazil. At the time of this spinosaur’s life, the region would have been marked by a series of shallow lakes that stretched into what is now Africa. Eventually, South America and Africa would obviously separate, but in the early Cretaceous they were close enough to allow spinosaurs to move and specialize in both continents.

Spinosaurs in both South America and Africa appeared to be formidable predators. They all possessed long, crocodile-like mouths loaded with thin, pointed teeth that were primed for eating fish, although we have some evidence that they weren’t so picky that they wouldn’t much on something like a pterosaur if given the chance. Most species probably hunted from the shores of the aforementioned lakes, moving about on their hind legs like other predatory theropods. However, Spinosaurus specifically may have spent more time in the water, as some of the skeletal fragments that have been found look like they came from a more horizontally-oriented swimmer, although that’s still a matter of some debate among researchers.

Bones as ballast

This new femur then adds a new wrinkle to spinosaur ecology. The bone came from a large animal, estimated to be around 33 feet long when it died, but young enough to probably still be growing. This fits with spinosaurs’ general position as apex predators in their ecosystems, no matter if they were swimming or just wading along the shore. Most importantly, the femur was very dense and heavy, contrasting most other dinosaurs’ evolutionary paths towards lighter, more hollowed-out skeletons. The most likely advantage of that extra weight would come in the water— living animals from penguins to manatees have unusually heavy bones that help them sink in the water. This in turn saves them energy, as they don’t have to work so hard to remain submerged, a handy trick if you’re trying to ambush prey. This trait is also present in the African, more-aquatic Spinosaurus, but this new femur predates that species by ten million years, suggesting that an earlier shared ancestor was using its bones as ballast even further in the past. Perhaps being bogged-down in a lake was more widely spread among spinosaurs than previously understood.

Scant supply of skeletons

This may sound like a lot of speculation for some rather eye-catching dinosaurs, but many of the aforementioned animals are only known from a small number of bones. Spinosaurus has a famously rough past, with our conception of the creature’s anatomy likely being cobbled together from multiple specimens, and possibly multiple species. In Brazil, the fossil record seems to practically be trolling paleontologists— a spinosaur named Irritator challengeri is known from a skull missing it’s snout, while Angaturama limai is known only from a piece of snout. To top it off, those two species may actually be from a single lineage, with the bones actually representing a single species at two different ages. Fossils aren’t easy to come by, but it’s odd that a large, thick-boned predator that spent a lot of time near underwater sediment wasn’t preserved more often, but for now, even the broken bones count for a lot. Researchers are hoping that the Araripe Basin will eventually yield some more complete specimens, possibly to answer questions about these dinosaurs’ posture, ecology and if all that time spent half-submerged in the water helped them grow to be the biggest predator to ever live on land.

Source: Brazilian sail-backed dinosaur swam long before by Franz Anthony & Julio Lacerda, Earth Archives

On May 10th, 2018 we learned about

Evidence related to the early days of our solar system found in an out-of-place asteroid

Found: Lost asteroid, spotted in the Kuiper belt, past Pluto

No collar or leash, but answers to the name 2004 EW95, and spots of  ferric oxides and phyllosilicates seem to be from asteroid belt near Mars. Please contact the Astrophysics Research Centre at the Queen’s University Belfast, UK if it’s yours.

Identifying an errant asteroid

Obviously, nobody is likely to respond to the above, because among other factors, nobody knew this asteroid was missing. When astronomers found the carbon-rich rock in the darkness of the Kuiper belt, they weren’t even sure of what they were seeing, as very little light can really be reflected off an 186-mile-long object 2,788,674,218 miles from the Sun. Still, it a wider range of light than its neighboring pieces of ice and rock, which is why researchers started to suspect that it wasn’t originally from that part of the solar system.

Most asteroids in the Kuiper belt are rather dull to look at. They don’t offer much variation in the frequencies of light they reflect off their surfaces. 2004 EW95, on the other hand, reflected light spectra consistent with  ferric oxides and phyllosilicates, minerals that would have originated closer to the Sun when our solar system was forming. Subsequent observations and careful analysis eventually confirmed this composition, strongly indicating that 2004 EW95 had been formed in the asteroid belt, not the Kuiper belt.

Launched by planets on the loose

This then raises the question of how this particular asteroid would have ended up so far from home, although that’s a question astronomers are happy to answer. Multiple models of the formation of our solar system include a period of time when the gas giant planets, like Saturn and Jupiter, were not in stable orbits around the Sun. The extreme mass and therefore gravity of these planets would have shoved and smashed smaller objects around them, possibly even clearing the inner solar system of many of the asteroids that were once closer to the Sun. If these models were true, it would be likely that some objects would have been launched by the gas giants’ gravity into deeper space. So the likely relocation of 2004 EW95 in the Kuiper belt is the first direct evidence to support these models.

Since Jupiter, Saturn and Uranus now have more stable orbits, 2004 EW95 probably won’t get pulled back to the asteroid belt any time soon. However, it may not be too lonely (do asteroids get lonely?) as astronomers have spotted other rocks that probably immigrated to the Kuiper belt before. However, the size, distance and darkness make confirming an asteroid’s composition difficult, which is why 2004 EW95 is the first time we’ve been able to more thoroughly vet what one of these lost rocks was made of.

Source: Exiled asteroid discovered in outer reaches of solar system, EurekAlert!