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This is one of those silly questions people ask as a joke, such as “Can you daydream at night?” or “Can a short person talk down to a taller person?” or “Can crop circles be square?” But I think this question is worth considering. Seriously, what happens to sound when you travel at the speed of sound? First, what exactly is the speed of sound? This is how fast sound waves—vibrations, in other words—travel through a particular medium. The speed is different depending on the medium. For example, sound travels 4.4 times faster through water than through air. And with air, the speed depends on the air’s temperature and composition. At 68º F (20º C), sound travels at about 767 miles per hour (1,235 km/hr). So, we’ll use 767 mph as a standard for this discussion. When we hear something, our brain is interpreting compressive waves that hit our eardrums. If you were capable of running away from those waves faster than the waves travel, then you wouldn’t be able to hear any sounds coming from behind you because you would be outrunning them. If you were running into waves coming at you from in front, you would be able to hear those. The thing is, no one can run at 767 mph. In fact, if you were in a jet going that fast and you stuck your head out the window, the effects of the air hitting your head would be devastating. You simply cannot move that fast in the atmosphere without being inside a protective environment like a jet. A streamlined, reinforced jet can withstand the constant impact of all that air. Humans cannot. The air inside of a jet is moving with you, so you can speak to the people around you and hear them normally. This is also true when you are standing in your yard talking to someone—the Earth is orbiting the sun at a speed of 67,000 mph, but you are safely within its bubble of atmosphere, like being in a jet. Interestingly, if your jet is moving faster than the speed of sound, the air in the cabin is moving with the jet, so when you speak toward the front of the jet, your sound waves are moving faster than the speed of sound (but the sound is still only moving at 767 mph relative to the air in the cabin). Weird. If a jet is traveling toward you faster than 767 mph, you cannot hear it approaching because it is outrunning its own sound waves. However, when the jet gets parallel to you, the sound waves will eventually reach your ears. If the jet is high above, it may already be past and out of sight before you hear it because the sound waves also have to travel from the jet’s height all the way to your position on the ground. If the jet is 40,000 feet (7.6 miles) high, the sound takes about 35 seconds to reach you. To answer the original question: a jogger cannot run anywhere near the speed of light. Let’s imagine that you and your jogging partner get in a car that goes faster than sound. No problem—you both are in an enclosed space (like in a jet) and the air inside is moving with you. Okay, let’s imagine that you and your jogging partner get on two motorcycles that can go faster than sound, and you ride beside each other. You would need helmets to protect your heads, of course, and if you tried to yell at your partner, the sound waves would be left behind and your partner would not hear you. However, you could talk using radio headsets inside your helmets because radio waves travel at the speed of light—waaaay faster than 767 mph!  Photo Credit: - Two fast joggers - Midjourney 7
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I'm fascinated by flightless birds... I have a novella titled Blue Arrow (it's connected to the Diffusion series). Weird title, huh? Well, there's a hiking trail, called the Blue Arrow trail, in Queensland, Australia that Trish and I first hiked way back in 1995, then again in 2018. At the time of our first hike, there was an amazing bird that roamed the area of the Blue Arrow trail. The bird, a Cassowary, was known to sometimes chase hikers, and locals had named the bird Blue Arrow. The novella's title refers to this cassowary. Let's learn more about cassowaries. The Eastern Turkey is possibly the most impressive bird you’ll see here in Missouri. When you see one, you think, “Cool, a turkey.” But when you lay eyes on a cassowary, you think, “Holy !$*#!, it’s a dinosaur!” (by the way, birds are now officially classified as dinosaurs... I wrote about this a few months ago) The cassowary is the second heaviest bird (the Ostrich is first), and they live in northern Australia, New Guinea, and the surrounding islands. In 1995, when we hiked the Blue Arrow trail, Trish and I searched for Blue Arrow the bird (without success). On another hike not too far from there, we were lucky enough to see our first cassowary. We recorded some video of it. However, though we were both teachers at the time, we could never show that video to our students because Trish, who was holding the video camera, kept exclaiming, “Oh, Sh**! Oh, sh**! It’s a cassowary!” Yeah, it’s that exciting to see one. The first photo isn't the greatest (I had to scan the original 1995 photo), but I wanted to show you the actual cassowary we saw 30 years ago. It came down from the hills to drink water. Cassowaries, which are about five feet tall and weigh up to 130 pounds, have a reputation for being aggressive (although, as is often the case, people’s opinions about this are sometimes exaggerated). When we hiked in areas where cassowaries lived, warning signs were posted at trailheads, and brochures about them were readily available. When Australians describe the dangers of cassowaries, they are fond of using the word “disembowel.” An unpleasant word, by any measure, but a cassowary has very sharp claws on its three dinosaur toes that are capable of doing some serious damage (see the second photo). Especially notice the claw on the right. You should also know this foot is at least at large as my hand. Cassowaries have a large, bony helmet, or casque, growing from the top of the head, but no one is quite sure of its function. Researchers have suggested it is used as a battering ram to protect the head as the bird runs through the thick tropical forest at up to 31 mph (50 kph). However, it seems more likely the casque is used in communication, perhaps as an amplifier or receiver of the cassowary's low-frequency vocalizations. Also, the casque may serve to dissipate body heat in hot weather. Cassowaries can jump 7 feet straight up, and they can swim wide rivers. Impressive birds, huh? During our return trip to northeast Australia in 2018, a hen cassowary and her chick wandered into the courtyard of one of the lodges we stayed at (third photo).    In March, before everything turned green around here, I hiked to the nearest cove to take some photos of bald eagles, which are fairly common around Truman Lake. The first photo is a juvenile (or subadult) bald eagle. I would guess this eagle is two to three years old. How can I tell? Because the eagle is starting to get white spots on its chest and head. In their first year, bald eagles are almost completely dark, with very little white specks. Gradually, they start showing more and more white spots. It isn't until the end of their FIFTH year that they finally display the classic "bald eagle look," with a completely white head and dark body. The second and third photos show an almost mature bald eagle that landed next to the water to get a drink. It's probably in its fifth year... notice it still has some dark feathers on its head and some white feathers on its body. By next year, this eagle will have a completely white head and dark body. The fourth photo is a mature (more than five years old) eagle in its nest, probably already with eggs that were getting ready to hatch at the time (March)—in Missouri, bald eagles often hatch out in April. This eagle was watching me carefully, making sure I kept my distance.     Photo credit: Bald eagles - Stan C. Smith A few days ago, Trish and I were driving home on one of the roads near our property when I spotted a snake crossing in front of us. It was stretched out in the center of our lane, and I managed to drive directly over it without touching it with the tires. Just before passing over it, I recognized the yellow dots over its black background color. Excited, I shouted, "That's a speckled kingsnake!" I slammed on the brakes, pulled over, and jumped out. By this time, the snake was in the grass beside the road, and I was able to get some photos with my phone. Why was I so excited? The speckled kingsnake is one of my favorite snake species, and I haven't seen one in the wild for a decade or more. They are beautiful snakes, with exactly one yellow dot on each shiny black scale. Although these snakes act rather feisty when you first approach them, if you pick them up, they quickly calm down and rarely bite. Kingsnakes are NOT venomous. Kingsnakes are constrictors, meaning they grab their prey, wrap around it, and squeeze. This does not crush the prey. Instead, it simply constrict's the prey animal's chest so that it cannot breathe, and the animal suffocates. Then the snake will swallow the prey animal whole. If you look closely, notice this kingsnake seems to be missing its right eye, whereas its left eye is fine. This type of injury is surprisingly common in snakes that eat rodents. Mice and rats are tough critters, and they tend to fight back, often getting in a bite or two before being overwhelmed and suffocated by the snake. Interestingly, kingsnakes, including the speckled kingsnake, regularly prey on other snakes. This includes venomous snakes, and they seem particularly fond of copperheads. This appetite for rodents and venomous snakes makes the kingsnake a friend to many farmers and other rural folks. Personally, I think they're awesome!   In the 1978 movie, Superman: The Movie, Superman appears to fly around the earth so fast that the earth stops spinning, then it starts spinning in reverse, thus turning back time so he could save Lois Lane. Well… true Superman fans will say, “Hey! What really happened was that particular Superman—the Silver Age Superman from the comic books—could travel back in time under his own power, and the movie showed the earth reversing its rotation simply to show that time was backing up. But I digress. Back to the question: What would happen if the world really did stop turning? First of all, this is unlikely to happen abruptly. Why? Because of the immense momentum involved in Earth’s rotation. Scientists estimate this planet has a mass of 5,974,000,000,000,000,000,000,000 kilograms (otherwise known as six ronnagrams). At the equator, the surface is spinning at 1,037 miles per hour (1,670 km per hour). The amount of force it would take to suddenly stop this spin is almost incomprehensible. And, to be honest, the entire planet would probably break apart in the process. But, for the sake of curiosity, let’s say that somehow Earth suddenly stopped spinning without the planet self-destructing (maybe because of magic? I don’t know… let’s just run with it). If that happened, the result is… death and destruction. Here are a few of the many reasons. First, the earth’s surface is spinning at 1,037 miles per hour (although somewhat slower as you get farther from the equator). If the spin somehow abruptly stopped, everything on the earth, including people, would continue flying east at hundreds of miles per hour, slamming into trees, or each other, or whatever. If you jump out of a car going 60 mph, you probably won’t survive. Now imagine jumping from a car going a thousand miles per hour. Only at the north or south pole (where there is almost no eastward motion) would you survive. But not for long… We can assume the water of the oceans would be thrown eastward with just as much speed, resulting in massive tsunamis. We can also assume the atmosphere will continue eastward, producing winds faster than the shockwave of a nuclear explosion. Winds this fast would destroy everything, leaving the surface as smooth as a billiard ball. Okay… for fun, let’s say that everything stops when the earth stops, including people, water, and air, and we are all still alive (more magic). But, with the earth no longer spinning, half of the planet would constantly face the sun and become really hot. The other half would be in constant darkness and would freeze. The only moderate area would be a narrow strip around the border between the light and dark side. Unfortunately, that won’t be safe either… The iron core of the earth would stop spinning also, which means the planet would lose its protective magnetic field. Radiation then would kill whatever is left. I just thought you might want something to think about during those nights when you can't sleep. You're welcome.  Image Credit: Destroyed Earth - Midjourney 6.1 On a recent hike to the nearest cove of the lake, I photographed a pair of white pelicans swimming about and hunting for fish. White pelicans don't breed in Missouri, but they pass through in the spring on their way to their breeding grounds in the northern US and Canada, and again in the fall as they move to their wintering grounds in the southern US and Mexico. They often take a resting break from their migration, and we sometimes see hundreds of them at a time. White pelicans are one of the largest birds seen in Missouri, weighing up to twenty pounds. Astoundingly, their wings stretch nine feet from wingtip to wingtip. In the spring, as breeding time approaches, adults grow a vertical flat plate on the top of their bill (look closely at the two birds in the first photo, and the second photo shows the plate more clearly). They use these plates for courtship and in conflicts to establish their territories. Interestingly, after the eggs are laid, the adults lose these plates. So, the pelicans we see migrating south in the fall do not have these plates. A very strange bird is the pelican. His beak can hold more than his belly can. He can hold in his beak Enough food for a week. And I'm damned if I know how the hell he can.   Photo credit: White pelicans - Stan C. Smith Often touted as an impossible conundrum, this question is actually easier to answer than you might think. The answer is, quite clearly, the egg. We simply need to go back in time to examine things. The first eggs with waterproof shells that could be laid on land appeared about 312 million years ago. Most biologists agree that domestic chickens came from a tropical bird that still exists today in the forests of Southeast Asia, called the red junglefowl (Gallus gallus). Humans began domesticating red junglefowls about 10,000 years ago, eventually creating a new bird subspecies (Gallus gallus domesticus… aka the chicken). As you know, humans eventually spread domestic chickens around the world. So, in one respect, eggs obviously predated chickens by hundreds of millions of years. But this is an oversimplification of the question. Let’s consider the very first chicken—the very first individual that had the genetic characteristics that made it a new subspecies. Well, genetic variation comes about through a process called mutation. This is true whether we’re talking about life forms that live wild, or those that humans breed for certain desirable characteristics. The genetic variation comes from the same phenomenon—mutations. These mutations cause new physical traits, and these traits are selected, either by the forces of nature (natural selection) or by humans (artificial selection). Sometimes the mutations cause changes that are significant enough that the new individual is considered a new subspecies or even a new species (this usually occurs incrementally over time, but sometimes it can happen relatively quickly). Anyway, long ago, there was a time when a male red junglefowl mated with a female red junglefowl, and a mutation occurred in the process of the male’s sperm cell fertilizing the female’s egg cell. The mutation resulted in the very first bird that could be considered a chicken (Gallus gallus domesticus). This fertilized egg formed a chicken egg, with the embryo developing inside the egg. The very first chicken hatched out of that egg. So… the first chicken egg came before the first chicken. Mystery solved, right? But wait! If you think about it, that very first chicken came from an egg that developed inside a female red junglefowl. That means the egg was a red junglefowl egg. And the first chicken egg didn’t exist until that first chicken grew up and laid her own chicken egg. Which means the chicken came before the egg! Now I’m just confused.  I recently shared images of some hooded mergansers, showing the striking differences between the drakes and the hens. Another species I saw a few weeks ago (most of them have moved on north by now) is the common goldeneye. The first photo is a drake, the second photo shows a drake and a hen. Common goldeneyes are diving ducks, which means they dive all the way underwater to search for food. They are primarily predators, eating small fish and aquatic invertebrates like crayfish. They also eat plant material, but plants make up less than 25% of their diet. It's fun watching them feed because they synchronize their dives... the group (sometimes up to twenty) will disappear underwater all at once, which I suppose helps confuse the prey animals, making them easier to catch. They stay underwater for as long as a minute, then they all pop back up to the surface. Like the hooded merganser (and the wood duck), common goldeneyes nest in cavities in trees. They breed in northern Canada and Alaska. I also included a couple photos of a drake mallard that was feeding close to the shore. Mallards are dabbling ducks, rather than diving ducks. Instead of diving all the way under, they just tip their body and submerge their head in shallow water to feed on plants and seeds (though they also eat small animals to get more protein during the breeding season). There you go... another dose of quacky facts.     Photo credit: Goldeneyes and mallard - Stan C. Smith A few days ago, I was walking along the shore of the lake cove about a half mile from our house when I came upon a stone half buried in the mud. Seeing it had an unusually smooth shape, I pulled it out. This is what I found.   I'm not a serious collector of stone artifacts, and I honestly don't know much about them, so I sent photos to my son Ryan, who posted them to a Missouri artifacts Facebook group. Based on its shape and large size, the consensus seemed to be that it is likely an adze. Or possible an axe. Both of these are tools that were often used for woodcutting (and cutting many other things). For shaping canoes, tool handles, and anything else made of wood. Also used for digging. So, what's the difference between an adze and an axe? They have similar uses, but an adze has the blade positioned perpendicular (at a 90° angle) to the length of the handle (see the tool on the right below in the third photo). An axe, on the other hand, has the blade positioned parallel the handle (the tool on the left). If my artifact is an axe or adze, maybe it was positioned on the handle in such a way that both sharp ends could be used... one end with a flat, chisel-like tip, the other end with a more rounded tip. A dual-use tool. It's also possible this artifact is a spear tip. But most spear tips have a sharper point than this, which is why the consensus was a woodworking tool. How old is it? That's a much harder question to answer. Some of the oldest artifacts in Missouri are from the Clovis culture. The Clovis people were nomadic hunter-gatherers that were in the area of Missouri from about 13,000 years ago (maybe more) to about 10,000 ago. Their stone points are distinct in shape, different from the one I found. So, I can assume it was likely made in the last 10,000 years. But my limited knowledge ends here. I simply don't know. Still, I find it fascinating to imagine the person who made this tool. What was he (or she) like? What kinds of animals did this person see that are now long extinct? Did this person stand in the exact spot where I was standing when I found the artifact? Did the person think about love and joy and beauty? I wish I knew.  I recently hiked to the nearest cove of the lake to photograph wildlife. Several hooded mergansers were there, swimming about and diving underwater to hunt. In my opinion, hooded mergansers are among our most beautiful ducks. This first photo is a drake (a male) I saw:  Mergansers are mainly fish eaters, and they dive underwater to catch small fish, crayfish, and other aquatic animals with their long, narrow bill, which has sharp serrations to grip their prey. Hooded mergansers nest in cavities in trees rather than on the ground like many other ducks do. Only one day after hatching, all 7 to 15 of the tiny ducklings leap from the cavity all the way to the forest floor. Then the mother merganser leads them to the nearest body of water. In order for this to work, all the eggs must hatch on the same day. So, the mother waits until she has laid all of her eggs before she starts incubating them. This results in synchronous hatching. Like many ducks, hooded mergansers have extreme sexual dimorphism—the males and females look very different. In this photo, you can see the differences between two females and one male. Cool, huh?  Photo credits: Hooded mergansers - Stan C. Smith |
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