First, in case you don't know, scorpions belong in an order of arachnids (spiders and kin), with 2,500 species around the world, on every continent except Antarctica. Scorpions have been around for 435 million years. They mostly live in desert regions, but some are adapted to other environments, including the striped bark scorpion that lives here in Missouri. The first photo is a striped bark scorpion I found under a rock near our home. The second photo is another striped bark scorpion, this one under a blacklight, which emits ultraviolet light. Scorpions glow a vibrant blue color in UV light, which can come from an artificial blacklight or from natural moonlight. But how? And why? Let's figure this out. Interestingly, each time a scorpion sheds its exoskeleton, the scorpion doesn't glow like this until the new exoskeleton hardens. There is a biofluorescent chemical in the exoskeleton that glows, but that chemical doesn't appear there until the shell hardens (which takes about 90 minutes). The chemical could be a by-product of the hardening process, or it could be secreted soon after the shell hardens. We don't know for sure. Anyway, the bioflourescent chemical absorbs UV light, then re-emits it as visible blue light. That's the how. Now let's consider the why. Well, no one is really sure why scorpions glow in UV light. One idea is that it helps scorpions find each other. Another idea is that it might confuse their prey, making it easier for them to hunt. A particularly intriguing idea (my favorite) is that the bioluminescent material makes the scorpion's entire body a kind of eye, to help the animal avoid sunlight. In general, scorpions avoid sunlight and moonlight (which is sunlight reflected off the moon). Scorpions are nocturnal, and they are much less active on moonlit nights. If the scorpion's body detects very much UV light (and therefore glows), this tells the scorpion to stay underground instead of hunting. Photo Credits: - Striped Bark Scorpion (daylight) - Stan C. Smith - Striped Bark Scorpion (blacklight) - DepositPhotos
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Caution: Mind-bending concepts ahead... Perhaps you’ve heard of light sails (or solar sails). These are huge parachute-like sails that can be expanded in space to allow the pressure from light emitted from the sun to propel a spacecraft. The first spacecraft to demonstrate that this actually works was the Japanese craft IKAROS in 2010. Think about how odd this seems—light emitted by the sun can actually push something. This must mean that light must weigh something, right? Well, first it’s important to understand the difference between weight and mass. MASS is the total amount of matter, or stuff, an object contains. WEIGHT is the force of gravity on an object. I typically weigh 190 pounds (86 kg). On Earth, my weight and my mass are the same—190 pounds. But, if I go to the moon, where there is less gravity, my weight and mass are no longer the same. My mass is still 190 pounds, but my weight is only 32 pounds. On Mars, my mass is still 190 pounds, but I weigh 72 pounds. Remember, mass is how much stuff there is in an object, so mass does not change in situations with different gravity. Weight does change. Light is made up of photons, and photons do not have mass. So, a simple answer to this question is NO… light does not have mass, and therefore it does not have weight. But things aren’t that simple. Light actually has momentum (if you’re wondering how something without mass can have momentum, that’s beyond my ability to explain… it has to do with the fact that light also has energy… light is kind of weird). Anyway, light does indeed have momentum, and it can exert pressure on a surface. This is why light sails work. This is why, when I stand in direct sunlight, I weigh slightly more than when I stand in the shade. The sunlight from above pushes me downward with a slight amount of force. On a sunny day, the city of Chicago weighs 140 kilograms more than at night, simply because sunlight is pushing down on it. Here’s a tidbit that blows my mind: If you captured all the sunlight falling on Chicago in any moment and put that sunlight in a box that has perfect mirrors on the inner walls—mirrors that reflect 100% of the light so that the photons are continually reflected back and forth in the box, the box would then weigh 140 kg more than it did before. And in space, where the box has mass but no weight, more force would be required to accelerate the box. So, this seems like light has mass, right? Not exactly. Because it is the energy and momentum of the light that causes this to happen. Instead of saying the light in the box has mass, it is more accurate to say the light in the box contributes to the total mass of the box. What a weird and wonderful universe we live in! (this is a conceptual image of a spaceship with a solar sail) Photo Credits: - Ship with solar sail - Midjourney v. 6.1 Trish and I recently spent a week at the Author Nation conference in Las Vegas. We were so busy learning and being inspired by other authors that we hardly even had time to leave the hotel. However, our room had a great view of the skyline, including the amazing new structure called The Sphere.
This beautiful but rather gaudy structure is a wonder of technological achievement, so I thought you might want to know some interesting facts about it. First, The Sphere is the largest spherical building in the world, at 366 feet (111 m) tall and 516 feet (157 m) wide. For reference, the Statue of Liberty (including the statue and the pedestal) is 306 feet tall and could easily fit inside The Sphere. To position the pieces, they used the fourth largest crane in the world, which had to be brought from Belgium for this job. The exterior shell is actually an elaborate spherical video screen, consisting of 1.2 million programmable LEDs. That's 580,000 square feet (53,880 square m) of screen. The videos are clearly visible even in daylight. And, from what we could tell, the videos run 24 hours a day. Of course, Vegas is illuminated by countless other gaudy light displays, so what's another 1.2 million more? Although I haven't seen the inside, it's supposedly just as impressive, if not even more so. The inside is a concert stadium with 18,600 seats, and with standing room for another 20,000 people. Get this... 10,000 of those seats are extra special. They provide an immersive experience, with specialized sound systems, haptic seats that make the guests “feel” sound vibrations, and machines that create wind, temperature, and even scent effects. I'm not even kidding. Yes, there's a concert stage, but the interior screen is the highest resolution screen in the world (268 million video pixels with 16K resolution). Supposedly, this makes it ten times clearer than the best HD TVs on the market today. To make sure the concerts are loud enough, there are 1,586 loudspeakers. So, you might be thinking... Cool, I want to experience it! Or maybe... Yuck, that's too much light and sound! At least now you know more about it. Seriously, who made this town in England the boss of time? And why? Let’s start with some history. Throughout most of human history, the best way humans could keep track of time was to look up at the sun and make an estimate based on its position. Eventually, clocks were invented, dramatically improving punctuality. By the 1800s, clocks and pocket watches were accurate to within less than a second. The problem was, people in different places set their clocks differently, usually based on when the sun would set or rise. The result? Times were different in different places, and when people traveled, they would have to reset their watches whenever they arrived at a destination, to match the local time.
This got to be a serious problem in the 1800s when railroads became a popular way to travel. Imagine trying to run a complex schedule of arrival and departure times when each location had clocks that were slightly out of synch with other locations. A lot of people missed their trains because their own clocks were different from the railways’ clocks. In the 1850s, countries in Europe decided to establish a standard time, such as London time for all of England, and Rouen time for France. However, the USA was so large that, on November 18, 1883, the US adopted four time zones, which were meticulously established by a group of railroad operators. Each time zone had a standard time that everyone could set their clocks to. Well, that’s fine and dandy, but it did not meet the need for a standard global time. So, in 1884, the US held the International Meridian Conference in Washington D.C. Experts from dozens of countries attended, and the group selected the global prime meridian (a prime meridian is an arbitrarily chosen line of longitude defined as zero degrees) as the starting point to measure all time zones. This line of longitude passes through Greenwich, England, so it’s also called the Greenwich Meridian. Why choose the Greenwich Meridian to start all time zones? Because, for centuries, Greenwich was home of the Royal Observatory. The clock there was already being used to set the official London time. At that time, the British Empire had a huge impact on international shipping, and the British had created countless sea charts and schedules based on Greenwich Mean Time that were already used by mariners from many countries. So, it seemed a natural choice for the entire world to set all clocks based on Greenwich Mean Time. Then, of course, people had to go and mess everything up with pesky daylight savings time nonsense. In my previous post, I went down a deep rabbit hole by exploring reports of raining fish and frogs. That really does happen (though always with a plausible scientific explanation). But what about when people say it’s raining cats and dogs? Where did that come from? Has it ever actually rained cats and dogs? Almost certainly not, but I still find the saying to be interesting. The first recorded use of the phrase was in 1651, in a poetry collection by British poet Henry Vaughan. A year after that, the British playwright Richard Brome included this line in one of his comic plays: “It shall rain dogs and polecats.” The phrase didn’t become popular, though, until 1738, when Jonathan Swift wrote a satire in which one of his characters feared it would “rain cats and dogs.” But this doesn’t really explain why this particular phrase became popular. Why specifically cats and dogs? One hypothesis comes from etymologists—people who study the origins of words. The Norse god of storms, Odin, was often depicted alongside dogs and wolves, which at that time were symbols for wind. Also, witches were thought to ride their broomsticks during storms, and they were often depicted with black cats. The black cats therefore became signs of approaching rain for sailors. So, “raining cats and dogs” may have been a way to refer to a storm with wind (dogs) and heavy rain (cats). In my opinion, though, a more likely origin of the phrase might be indicated by something else that Jonathan Swift wrote. In 1710, he wrote a poem called “City Shower.” Many cities had poor drainage in those days, and the poem describes the flooding that would occur after heavy rains, and how the flooding left dead animals in the streets. So, I’m going with the explanation that these dead animals led people to describe the storm as “raining cats and dogs.” Okay, I'm now satisfied I have fully explored the weird notion of animals raining from the heavens. I shall pontificate on this matter no further. Image credit: Midjourney 6.1 I went down a rabbit hole with this one, so bear with me... it'll be worth the time it takes to read it.
All the way back to ancient civilizations, people have reported seeing frogs and fish rain from the sky. And other animals, like rats, iguanas, bats, and spiders. I’ve always wanted to know why people would make such an obviously outrageous claim. I mean, even if I saw it happening, I would think twice about going around telling people what I saw. They would think I was crazy. So, why have people made these claims throughout history? One explanation, at least with frogs, is that, after emerging from their houses after a heavy storm and seeing frogs everywhere, people made the assumption the frogs fell from the sky during the storm. The 1999 movie Magnolia (considered by many to be a cinematic masterpiece) has a famous—and rather graphic—scene where thousands of large frogs fall from the sky. To most viewers, it was confusing, but the movie critics claimed it was the perfect ending. Go figure. Anyway, the movie was obviously fiction. Here are some things we know for real. Ernest Agee from Purdue University said, “A tornadic waterspout is merely a tornado that forms over land and travels over the water. I’ve seen small ponds literally emptied of their water by a passing tornado. So, it wouldn’t be unreasonable for frogs (or other living things) to ‘rain’ from the skies.” So, waterspouts are likely to be the source of some of the reports of such things. In 1873, it actually rained frogs in Kansas City, and a Scientific American article concluded it was likely due to a tornado. In 1882, in Dubuque, Iowa, there was a frog hail storm, in which frozen frogs fell from the sky during a storm. Scientists concluded a powerful updraft must have carried frogs high into the atmosphere, where they turned into frogcicles and eventually fell onto the heads of puzzled Dubuque residents. In 1947, a biologist from the Louisiana Department of Wildlife was eating at a restaurant in Marksville, Louisiana. A waitress came up to him and said fish were falling from the sky. Later, he wrote: “There were spots on Main Street, in the vicinity of the bank, averaging one fish per square yard. Automobiles and trucks were running over them. Fish also fell on the roofs of houses… I personally collected from Main Street and several yards on Monroe Street, a large jar of perfect specimens and preserved them in formalin, in order to distribute them among various museums.” Keep in mind this was actually a biologist saying this. In 2005, thousands of frogs rained on a small town in northwestern Serbia. Almost laughably, a local climatologist, named Slavisa Ignjatovic, described the phenomenon as “not very unusual.” Why? Because, as he explained, the strong winds that accompanied the storm could have easily picked up the frogs. In 2010, the people of the small Australian town of Lajamanu witnessed hundreds of spangled perch falling from the sky. Christine Balmer, who was walking home when the rain and fish started falling, said, “These fish fell in their hundreds and hundreds all over the place. The locals were running around everywhere to pick them up.” In June of 2022, in San Francisco, anchovies rained from above. In this case, the weather was clear, and the falling fish appeared to have been chewed on. Scientists concluded this phenomenon was a result of an unusually productive year for the anchovy population, and sea birds were catching them and accidentally dropping some while flying. A similar incident happened in Texarkana, Texas in 2021, but in this case a large flock of cormorants were disgorging their recent meal of shad while flying. The yacked-up shad were on the ground over an area of nine square miles. So, there we have it. It does occasionally rain frogs and fish, and we have reasonable scientific explanations for almost every event. Below is a woodcut from a book titled Prodigiorum ac Ostentorum Chronicon, published in 1557, one of the first books specifically about strange phenomena. The woodcut depicts a reported raining of frogs that took place in Scandanavia. Many of the leaves have fallen now, but a few weeks ago, when Trish and I were sitting on our deck, I was staring at the leaves at the top of a nearby oak tree. Then I stared at the leaves at the bottom, then again I stared at the top. This is when I had an epiphany—in the category of Stan-discovers-something-all-true-botanists-probably-already-know. What did I discover? The leaves at the top of the tree are skinnier (less surface area) than those at the bottom of the tree. The difference is striking. So, I took two photos of leaves on the same tree. This first photo is leaves at the top. ![]() And this second photos is leaves at the bottom of the same tree: ![]() See what I mean? What's up with that?
Well, although I was proud of myself for making this acute observation, this was already a well-known phenomenon. There are several reasons the top leaves of tall plants have less surface area than the bottom leaves. The leaves at the top are in direct sunlight, whereas those at the bottom are shaded by the upper leaves. With smaller leaves at the top, more sunshine can get to the leaves at the bottom. And the larger leaves at the bottom can grab more of the light filtering through the top leaves. It's an equity issue, you see. The lower leaves can do their share of photosynthesis this way. There's another reason too. The top leaves are exposed to more direct sun and more wind, so they evaporate away more water. By having less surface area, they lose less of the precious water the tree needs to survive. At the bottom of the tree, the leaves are shaded, there is less wind, and the air is more humid. So, those leaves can be larger without evaporating away too much water. These kinds of adaptations always fascinate me, even if I'm late to the party. Several day ago, I was hiking in the forest near our property and I came upon this old fallen branch covered in what looked like ants... but many of them had wings and were flying away as more continued emerging from inside the dead branch. What's up with that?
Well, with some types of ants (as well as termites), the queen produces winged offspring at certain times of the year, and the winged individuals emerge and take off all at once, often thousands at a time. The question is, are these ants or termites? Let's start with a bit of background information. Both ants and termites have what is called their annual nuptial flight. Basically, this is when some of the ants (or termites) take off flying to find a mate. Ants and termites live in colonies, with a queen and a large army of non-reproductive female workers. During most of the season, the non-flying, non-reproductive female workers forage for food to feed themselves and the numerous larvae produced by the queen. This part of the year is for growing the colony. However, at certain times of the season, the queen changes her job. She stops laying eggs that hatch more non-reproductive female workers, and she starts laying eggs that hatch females that could become queens, as well as males that could mate with these females. These potential queens, and the males that could mate with them, have wings. They all emerge from the colony at once and take to the air, swarming about and mating (yes, they mate while swarming in the air... the little multitaskers). Once a winged female mates with a winged male, the male loses its wings and dies (bummer), and the female goes off to become the queen of her own new colony (yay for the queen!). As it turns out, the insects in the photo are ants. How do you tell if they are ants or termites? The easiest way is the body shape and the wing length. Zooming in on the photo, I could see a distinct constriction behind the head (a narrow neck). And with some of the winged individuals, you can see how the second pair of wings are shorter. Trish and I saw several other mammals in Panama besides the monkeys and sloths I’ve already posted. As you can probably imagine, mammals are often MUCH harder to spot than birds, which means photographing them can be a challenge. Names and descriptions are provided above each photo. Kinkajou. These tropical tree-climbing mammals are related to raccoons and coatis. Found in southern Mexico, Central America, and South America, they are difficult to see because they are nocturnal. I took this photo as this kinkajou was feeding on a banana outside a window of the Canopy Tower. Northern Tamandua. This is actually a tree-climbing anteater. This anteater specializes in raiding ant, termite, and bee nests high in the trees. Like other anteaters, it has no teeth, but it has strong claws for tearing into insect nests, and a long, sticky tongue for slurping up its prey. This is the only one we saw, and photographing it was a challenge, as it was high in a tree and very busy looking for food. Coati. Also known as the coatimundi. Related to the raccoon and kinkajou—one of the other mammals included in this post. Whereas kinkajous are usually seen climbing trees (they have a prehensile tail), coatis are usually on the ground (with a more raccoon-like tail), although they are also good climbers. Coatis often forage in groups, and they hold their long tails up high, which helps the others in the group stay together in thick vegetation. This one was on the move, refusing to pose for good photos. Central American Agouti. Fairly common in Panama, agoutis are rodents that can grow to almost ten pounds. They are often seen in gardens, as well as in the rainforest. Agoutis are active during the day, and they form monogamous mating pairs, sometimes for life. They have a rather odd courtship ritual. When the male is in the mood, he sprays the female with urine. If his timing is right, this will send the female into an excited dance. This, in turn, prompts the male to give her a few more nice urine squirts. You can guess what happens next. Proboscis Bats. These tiny bats were hanging around on the lower side of the trunk of a leaning tree. They usually live in colonies with as many as 45 individuals, roosting together like this during the day and hunting for insects at night. Most colonies have between 5 and 11 bats. These bats usually feed while flying just above a body of water (without actually touching the water), and this particular tree was actually leaning out over a portion of the large lake that is part of the Panama Canal (we were in a boat when we found them). Photo credits: All mammal photos - Stan C. Smith Everyone loves sloths, right? We were lucky enough to see and photograph a number of them. Mostly the BROWN-THROATED THREE-TOED SLOTH. I have to tell you a story about the sloth in the first photo. As we were just starting a hike, we saw this sloth high in a cecropia tree, hanging upside down and slowly scratching itself. I got some good photos, and we continued onward. When we came back down the same trail about two hours later, the sloth was still hanging there, and was STILL scratching itself. A good scratch cannot be rushed, I suppose. Why are sloths so slow? This question has puzzled biologists for centuries. Way back in 1749, when sloths were first described in scientific literature (by Georges Buffon), he referred to them as: "the lowest form of existence." This is obviously incorrect because sloths have thrived for 64 million years. They are very well adapted for their lifestyle. First, sloths are completely colorblind, due to a genetic condition that showed up in their ancestors millions of years ago. They see poorly in dim light, and hardly at all in bright daylight. Very few tree-climbing animals are colorblind, and this condition requires that they move slowly and cautiously. But that's not all. Sloths have extremely slow metabolism. In fact, their metabolism is so slow that they are unable to regulate their body temperature internally, like other mammals can. They regulate their temperature behaviorally, like a cold-blooded animal does, by basking in the sun when they are cool and moving to the shade when hot. Unlike other mammals, a sloth's internal body temperature can fluctuate as much as 20 degrees F during the day (this would be fatal to a human). These factors, among others, result in an extremely slow-moving animal. But this isn't a bad thing—it's simply a different way of surviving. Sloths are very good at what they do! The last photo is a HOFFMANN'S TWO-TOED SLOTH, which we saw in a sloth sanctuary. We only saw one of these in the wild, and it was not in position for good photos. Photo Credits: All sloth photos - Stan C. Smith |
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