Why Don't We Know What Color Dinosaur Skin Was?

Let’s think about how fossils are made. The usual way is for a plant or animal to die and become buried in mud at the bottom of a lake or sea. The dead organism begins to decompose; the soft tissues are broken down fairly quickly, but the bones and other hard structures like teeth can last a very long time (which is why we find more animal than plant fossils, and mostly bones and shells). Meanwhile, the mud around the organism slowly turns to rock, compressed by the weight of the water above. By the time the bones decompose, the rock around them is very hard and does not collapse under the weight of the water. The empty space left by the decomposing bones is filled with particles of mineral that filter in through tiny cracks in the rock. Slowly, the hollow spaces left by the bones are filled with rocks themselves, but these new rocks have the exact shape of the bones from the dead organism!


The thing to remember is that a dinosaur bone fossil is not really a bone at all. It is like those plaster casts of your hand that you brought home to Mom in kindergarten – only made of rock instead of plaster. The original skin of the dinosaur is long gone, and the fossils are the color of the minerals they contain.


Although we may never know if dinosaurs were striped or spotted or all one color, we do know a few things about their skins! Researchers have found several dinosaur fossils with visible skin texture. So far it seems dinosaur skin was more like ostrich skin than crocodile hide.


The discovery of bog mummies – I will write a separate post about them sometime – has given some people hope that somehow a dinosaur will be found preserved in such a way that DNA can be extracted from the remains. But 65 million years is a very, very long time, and it is hard to imagine cells staying intact in any environment for that long. Still, “hard to imagine” is not the same as impossible!

How Can I Stop Hiccuping?

A hiccup (or for all good folks of the British persuasion, a hiccough) is defined by the National Library of Medicine as “an unintentional movement (spasm) of the diaphragm, the muscle at the base of the lungs. The spasm is followed by quick closing of the vocal cords, which produces a distinctive sound.”

Which would make a hiccup an onomatopoeion, too.

Getting hiccups seems to be an integral part of the human experience. There are all kinds of supposed remedies for hiccups, most of them less than satisfactory. If aspirin had the same failure rate as all the different home remedies for hiccups, nobody would buy it anymore. Some people will advise you to drink a glass of water; others will tell you to drink it upside down (hey, if you start choking, maybe the hiccups will go away). One common trick is to hold your breath. Another is to have someone startle you, which usually only works after you have forgotten to expect them to startle you, by which time the hiccups may have stopped on their own. Personally, I have had the best luck emptying my lungs and holding my breath out. Nothing works all the time; some of them may not work for you at all. Still, I would bet that every one of us has been able to beat the hiccups at least sometimes. What is the best way to make them stop?

Going back to the definition of hiccups, we see that they are spasms (or quick involuntary movements) of the diaphragm, which is the large flat muscle dividing the chest cavity from the abdomen, and which we use to force air in and out of the lungs. So hiccups don’t just make it hard to breathe; they do so because they take over the function of the breathing muscle.

The trick to making hiccups go away is to regain breathing control. Any exercise, involving water or not, that helps you control your breath will also help rid you of hiccups. If it doesn’t work immediately, don’t give up. You are taking back control of your own muscle, and it will work if you persist.

Some cases of hiccups have a pathological cause, and need to be treated medically. The Guinness Book of World Records has Charles Osborne as the hiccup champion of all time; he was unfortunate enough to have hiccuped more or less continually for 68 years. There is no record of a cause for this lifelong affliction; but another man, Christopher Sands, suffered from hiccups for over two years due to a brain tumor putting pressure on certain nerves.

One thing makes more sense to me than the rest. The phrenic nerve is connected to the diaphragm, and seems to be involved in hiccuping. Some doctors advise pinching the skin over the deltoid muscle (the deltoid is the big muscle on the outside of the shoulder that looks like a triangle – or the Greek letter delta); a branch of the phrenic nerve passes over this muscle. Even if this doesn’t take care of the hiccups, it always feels nice to get a shoulder massage. I think next time I have hiccups, I will ask for a shoulder rub! If I can hold my breath and drink a glass of water while getting my shoulders rubbed, I think my chances are pretty good.

Good luck fighting the hiccups!

Of Honor And Motor Oil

I want to tell you about the best automotive service center in Texas. It’s Kwik Kar in Irving, on the corner of Esters Road and Pioneer Drive. Every location is independently owned, so I can’t vouch for the others, but that one is the best. By the way, this is not a paid advertisement. The folks at Kwik Kar have no idea I’m writing this. It is the result of gratitude.

The first time I went to Kwik Kar for an oil change, I went reluctantly. I usually change my own oil; it’s not hard, doesn’t take much time. I am the kind of guy who likes to do things myself if I can (and ever so often, when it might have been better to hire a professional). I enjoy fixing things, enjoy the feeling of having left something better than when I found it. Some people who know me well might say I am a bit of a perfectionist, a nit-picker, even a tough customer. They would be right. I demand a lot of myself, and no less of someone providing goods or services.

That weekend was a tough one. I had planned on changing the oil in my car – after changing the A/C compressor and power steering belts. This is usually a piece of cake – very simple. I had changed plenty of belts before. Famous last words!

After a couple of hours, I began to realize that my car had been designed by a team of highly skilled engineers whose main design objective was to keep me from changing the power steering belt. The other belt, the one for the A/C, was as easy as I had expected. But the power steering belt was a different story altogether. They had placed the tensioner bolt – the piece that needs to be loosened before removing a belt from a pulley – about a foot up from the bottom of the engine, right between the engine block and another very large part, in a crack barely wide enough to fit a butter knife. The thing is as close to the exact center of the entire motor assembly as anyone could wish it weren’t.

In the end I had to get a special tool made up of a very stubby socket for tight spaces, and a long flat handle about the thickness of a butter knife. Apparently I am not the only one who has had this type of problem. It still didn’t work. At this point I started to feel frustrated. I was tired, my back and arms were stiff and sore, and I had removed all the skin from my knuckles. So I went to Kwik Kar. After the oil change, I asked the mechanic if he had had trouble with the belt. “No,” he said, “It doesn’t need to be changed.”

“The other one was cracked,” I told him.

“This one wasn’t,” he replied. It was a $75 job, twice the price of the oil change. I thanked him, paid for the oil change, and left.

It is nice to find a business that provides good service at a fair price. When it is staffed by pleasant people, so much the better. The hard thing is to find all this, and the kind of old-fashioned ethic that truly puts the customer first, even ahead of legitimate profit.

Like anyone else, I have had repair shops try to take me for all they could. My wife once paid for an oil change, after which I found the same filter as I had put on her car the last time. That is one of the reasons I like to do things myself. Honesty is, unfortunately, something of an unexpected bonus these days.

The mechanic at Kwik Kar would have been perfectly justified in changing the belt on my car. I asked him for the service. He checked the belt, found it still good, and even put the little splash shield back in place that goes on the inside of the fender. Not only did he go out of his way to serve a customer, he did so in the process of saving the customer money at no profit to himself. That goes beyond honesty. That is something truly rare: honor.

I think I might just keep going back to Kwik Kar for oil changes. You should too.

Will We Ever Find A Dinosaur Frozen In A Block Of Ice?

I love the “Ice Age” movies. Who doesn’t? Granted, they kind of go downhill after the first one, but it’s a gentle slope, and making a sequel better than the original is arguably impossible. Don’t get me started on Star Wars.

One of my favorite scenes from “Ice Age” is the one where the oblivious Sid, lost in the ice cave and peering at the walls with his natural curiosity, is startled by a frozen fish with large needle-sharp teeth. He turns quickly away, only to be confronted with a much larger, much scarier specimen: a Tyrannosaurus Rex, razor jaws gaping, frozen into the icy wall. Sid continues past a row of frozen fossils in phylogenetic order; all share features in common with Sid. As he reached the end, he stops, completing a tableau of his own evolutionary history.

The last time I saw the movie, someone asked if a dinosaur had ever been discovered frozen in the ice. I said that we haven’t, which prompted the question whether we ever would make such a discovery. What a find that would be! Much as I love the idea, it is very unlikely. I don’t like to say “impossible” – too many things once considered impossible have already become reality – but in this case, it might not be too strong a word.

The frozen dinosaur in the movie was buried deep in a glacier. Glaciers are frozen rivers; they flow downhill towards the ocean just like any other river, but much more slowly. As the bottom of the glacier melts, the top is being formed out of snow that falls high in the mountains where the glacier begins.

For an animal to become trapped in a glacier, it would have to die high up in the snowy mountains where glaciers form. The animal would be covered over with snow that would slowly turn to ice as it built up over centuries. After some thousands of years, it might be found deep inside a glacier like the frozen dinosaur in “Ice Age”.

As far as I know, nobody has ever found an animal frozen inside a glacier. It may have happened, but I doubt it. Animals need food, and there is nothing to eat high up in the eternal snows where glaciers begin. Humans are the only things that climb around glaciers on purpose. If an animal got lost in the mountains, it would die long before it could reach the source of a glacier.

We have learned many things about dinosaurs since I was a child. Some scientists think that certain dinosaurs may even have been partly warm-blooded, like some fish are. But no one is suggesting that dinosaurs were able to live in icy Arctic conditions. There may have been mountains with glaciers during the Triassic, Jurassic, and Cretaceous Periods when dinosaurs were alive, but the dinosaurs would never have been anywhere near the tops of those mountains.

It is a pretty sure thing that no animal, much less a dinosaur, will be found preserved inside a glacier. But I still love the movie.

The Little-Known History Of Teddy Bears

Last time I went shopping for a child’s birthday gift, I was struck by how usual it seemed to be in a toy store the size of a big-box discount mart. When I was a child, the only real mega-size toy store in the world was Hamleys in London (still the world’s biggest!) For those of us not fortunate enough to live within pilgrimage range of Hamleys, the toy store was a small shop on the street, or a section in a department store. It has been many years now since I have seen a small toy store – I don’t even remember having seen a toy section in a department store recently. Come to think of it, since we have been back in the USA, I can’t remember having seen any toy stores at all except for the one big chain. I hope it’s my lack of attention and not an actual monopoly. The big retailer has a mind-boggling selection, more variety than I ever imagined as a child, but it just doesn’t feel like a toy store to me. Getting old, I guess.

I like the old toys, the ones I remember from childhood. The wooden train set, the LEGOs, the teddy bear. You know, the toys that have been around forever. Or have they? (Cue dramatic music.)

Of all the classic (or old-fashioned, depending on your point of view) pre-electronic toys, teddy bears are among the newest. They were first manufactured for sale in 1902 (LEGO goes back to 1934). There is no doubt that teddy bears had existed before 1902 – people have made stuffed toys for their own children for centuries, and dolls go back to the dawn of civilization – but nobody can verify dates for unique, home-made toys from hundreds of years ago, so toy history has to deal with factory-made toys available for sale to the public.

Of all toys, the teddy bear has the coolest legend behind its origin. President Theodore “Teddy” Roosevelt is usually credited with being the inspiration for the creation of the teddy bear. Unfortunately, this turns out to be not quite true. I can already hear the angry howls of outrage from Teddy Roosevelt fans everywhere. Slow down and give me another minute. The legend is true; it’s the connection to teddy bears that doesn’t quite hold water.

For those readers who don’t know what the fuss is about, the legend – which, I repeat, is completely true – goes like this:

President Teddy Roosevelt was an avid outdoorsman – a genuine tough guy who loved big-game hunting. His physical fortitude was matched by his strength of character, which fact explains his continuing stature in American history as one of our great leaders. In November of 1902, President Roosevelt was invited on a bear hunt by the governor of Mississippi. After a long, exhausting day of hunting, Roosevelt still had not bagged a bear. He may have been in a bad mood at that point – hard work with no results will do that to most of us – and some of the staffers hunting with him thought it would be a good idea to make sure the President got a bear. In the end, hunting guide Holt Collier, aged 56, went out and brought a large black bear back alive – an incredible feat for a single hunter before tranquilizer darts. The bear was exhausted and hurt; the staffers tied it to a tree, brought the President, and told him he could shoot the bear. To his credit, Teddy Roosevelt was disgusted. No self-respecting hunter would shoot an animal that way. He refused, to the surprise of lesser men present. People talked; the word spread. The ground was laid for the legend of the Teddy Bear.

On November 16, 1902, the Washington Post published a drawing by political cartoonist Clifford Berryman. The cartoon showed President Roosevelt refusing to shoot a captive bear. Most readers paid more attention to the picture than to the caption: “Drawing the Line in Mississippi.” Berryman was using the hunting incident as a metaphor for President Roosevelt’s attitude towards racism in the South (and Mississippi in particular). The President had openly criticized the Mississippi state government for failing to stop lynchings of black citizens. He had also made a friend of his hunting guide Holt Collier, which was only an issue because Collier was black. The icing on the cake, though, came when President Roosevelt invited Booker T. Washington to dinner at the White House. Washington, the great black orator, activist, and political advisor, had been at the White House before, but always on business. This was different; this was a social occasion. Racists were furious at such a public statement of race equality. Berryman’s cartoon was an acknowledgement of Theodore Roosevelt’s contribution to civil rights in America. But it was 1902; sixty years too early for civil rights. The cartoon inspired a Brooklyn shopkeeping couple, Rose and Morris Michtom, to make and sell small stuffed bears – called “Teddy bears”, of course. The toys became immensely popular almost overnight. Teddy bears became the most popular toys in the world; they still are today, after an 111-year run.

So where is the legend wrong? The problem is that, although President Teddy Roosevelt did indeed inspire the Michtoms to make toy bears, and although Berryman’s cartoon was directly responsible for the popularity of the teddy bear, the first factory-made teddy bears were made in Germany by Richard Steiff. There are at least two important facts supporting Steiff as the creator of the modern teddy bear, rather than Michtom:

First, Michtom’s toy bear was directly inspired by the Nov. 16, 1902 cartoon referring to the Roosevelt hunting incident. Even if the Michtoms could have gone from the idea stage to production of the first prototype bears, and sold them before Christmas, this places the origin of the toy bear in America at the very end of 1902. The Michtoms’ son Benjamin remembered a letter from February 1903 from his mother to the President, requesting permission to use the name “Teddy” to market the bears. This letter has never been produced, but it is reasonable to date the beginning of teddy bear production in America to the beginning of 1903.

Second, the Steiff factory did begin production of toy bears in 1902, although they were not called “teddy bears” until after the Michtom bears became popular by that name.

Third, the likelihood of Steiff producing toy bears before Michtom is increased by the fact that Steiff was an established toy factory that had been making stuffed animals since 1880. The bear was a new addition to a number of stuffed animal toys, the first of which was an elephant. The Michtoms’ business was stationery, not toys; the bears were made by Rose Michtom as a personal response to the Roosevelt hunting story.

So, although the legend of the Teddy Bear remains intact, it was responsible for the name and the popularity of the toy, not for the stuffed bear itself. It will always be a good story, and even more so if we remember the character and the values of the man who gave his name to a stuffed bear.


Why Is Our Clock So Messed Up?

One of my pet peeves – which, unfortunately, will almost certainly never change – is our system of counting time.

The standard number system for everything else in the world is the decimal system, or base-10. Place value in the decimal system is ten times greater to the left and ten times less to the right. For example, “333” means three ones, three tens, and three hundreds; “3.33” means three ones, three tenths, and three hundredths. Since five is half of ten, one half is written “0.5”. One fourth (half of one half) is “0.25”. Anyone who can read a price tag at the store can use the decimal system. It is beautifully simple to use; if you think I am exaggerating, try doing some long division with Roman numerals, or add up some groceries in binary (if you really enjoy suffering, use hexadecimal).

The decimal system is great. So why don’t we use it to measure time? An hour and a half is 1.5 hours, but when we write it in hours and minutes, it comes out 1:30 instead. This makes it difficult to calculate the cost of something per hour, because minutes are sixtieths of an hour instead of hundredths. If I rent a boat for $6.50 per hour, and I want it for three hours and fifteen minutes, I might try to multiply 6.5 times 3.15; I will end up owing money. Three hours and fifteen minutes equals 3.25 hours, not 3.15.

Here’s a simpler example. Imagine that I pay my son minimum wage – $7.25 per hour – to mow the lawn. When he finishes, the timer reads 0:35, or 35 minutes. To pay him, I have to divide $7.25 by 60 and multiply by 35. This is no fun.

What if there were 100 minutes in an hour instead of 60? Then I could just multiply $7.25 by 0.35 – a single operation instead of two.

If we divided the day (from sunrise to sunrise, or midnight to midnight) into 10 hours, each hour into 100 minutes, and each minute into 100 seconds, our timekeeping would be much easier. Of course, the minutes and seconds would be a little longer than they are now, but not that much. It would be far easier to teach children to tell time without all the twelves and sixties. Everything would be better!

So how did our clock get messed up? Why do we use a 12-base clock when everything else is 10-base?

The answer goes all the way back to the beginning of clocks. The first clocks we know of were sundials in ancient Egypt. Sundials are great when the sun is shining, but less so when it is cloudy, and not at all during the night. Ancient Egyptians divided the daylight into ten hours (sensible people!) but added a twilight hour at the beginning and another at the end of the day. Since their sundials did not work at night, this gave them twelve hours. Much later, after inventing ways to keep time during the night, people doubled the daylight hours for the nighttime. From sunrise one day until sunrise the next day, there were 24 hours (and still are today).

The number 12 works well with another number system, 60-base, which was used by ancient Babylonians (who were very good astronomers despite having a horribly clunky number system). The ancient people of India and Sri Lanka were also great astronomers and used 60-base systems; our word “hour” comes from the Indic word “hora”.

No matter how good ancient people were at astronomy, I think we would be better off with a decimal time system. But that is not likely to happen, because all the systems used all over the world by 7 billion people use the 12-base clock. Oh well!

If You Fell Through a Black Hole, Where Would You Go?

Black holes are definitely some of the most mysterious things in the universe. A hole that looks the same from all sides is quite a puzzle!

If I were to go up into the attic and saw a circular hole around me, I would fall down into the living room. Likewise, if there were a hole in my living room floor, I might keep falling down into the basement. This is easy to imagine. It is not too much harder to picture gravity reversing, so that I would fall up from the basement through the hole in the living room floor, ending up back on the couch where I started. In each of the three places I had been – the living room, the attic, and the basement – I could look through (or fall through) a hole to another space.

Before I start talking about black holes, I should say that everything we know about them is based on math. Until 1971, there was no observed evidence that they even existed. Today, there are many known black holes, but we will never see one of them directly, so all our knowledge of black holes is based on measurements of things happening in space that cannot be explained without the math model of a black hole. Most of my readers are not math professors, so you may be wondering what I mean by “math model”. If I tell you that I am thinking of an object that is 5 cm long, 5 cm wide, and 5 cm tall, you could guess that it is a cube. But what if it is a sphere? All you really know is how big it is. Now, if I tell you that the object has six square sides, you know it is a cube. You can picture it in your mind. There is no real cube, but your image of it is based on numbers I gave you. The cube in your mind is a math model.

Remember the holes in my ceiling and floor? Now imagine a hole in the middle of empty space. It is not a hole in a wall or anything else; it is a hole in space. You might be able to see the hole if you got close enough, but you would not be able to see through it. If you moved in a big circle around the hole, it would look the same from any angle! If you were to throw an object – like a marshmallow – through a hole in a wall, you could look over the wall (or through the hole) and see the marshmallow on the other side. But if you threw a marshmallow into a black hole, there is no other side. It is gone forever!

How can this be? About 250 years ago, a scientist named John Michell imagined a thing nobody had thought of before.

(Scientists of his time already knew that objects had to reach a certain speed to escape the gravity of any planet or star; this speed is called the “escape velocity”. The more massive a planet or star is, the faster an object has to move to escape out into space. This is why a rocket can get to the moon, but a bullet from a gun cannot. It is not fast enough. A rocket fast enough to escape the Earth’s gravity would still not be able to escape the Sun, because the Sun is so much more massive than the Earth. You would need a much faster rocket. On the other hand, if you have seen pictures of the Apollo missions to the Moon, the rocket they used to get off the Moon was not very fast at all. It didn’t have to be; the Moon is much less massive than the Earth, so its gravity is much weaker.)

John Michell imagined a star so massive that even light would not have enough speed to escape its gravity. If the light from the star could not escape out into space, then nobody would be able to see it! John Michell called his imaginary star a “dark star”. Later scientists, including Albert Einstein and Karl Schwarzschild, made math models of dark stars to describe the behavior of light and of objects that got close to them. It was a scary but fascinating idea! In 1964, a journalist named Ann Ewing wrote a report about these math models. The report was called “Black Holes In Space”. Since then, people have been calling them “black holes”.

Even though many scientists made lots of math models of black holes, nobody had ever seen one. They are, after all, invisible! Between 1971 and 1973, a team of astronomers watched a giant star far out in space. It behaved unlike any other star. By 1973, they knew from their measurements that the star had a black hole next to it, just like you knew (after getting enough information) that the object I was describing was a cube. The star system fit the math model: it could only be a black hole!

That first observed black hole is called Cygnus X-1. Since then, we have observed many other black holes. Although they are invisible, we know they are black holes from observing what happens around them. If it fits the math model, it must be a black hole.

So what is the answer to the question we started with? If you fell into a black hole, where would you go? By now, you know that black holes are not really holes at all. They are objects with such strong gravity that nothing, not even light, can escape them, which is why they are perfectly dark. Because its gravity is so strong, anything that falls into a black hole is crushed into zero volume. Since one of the properties of matter is that it takes up space, objects falling into a black hole would really not even be objects anymore. The center of a black hole is called a “singularity”, and the math model for a singularity seems to break the rules for what we know about the universe.

Black holes may always be one of the universe’s mysteries!

How Do Baby Turtles Know To Crawl Towards the Water?

There is a beautiful park a couple of blocks from my house. Groves of big shady trees line the shores of the lake; the footpath winds through the trees, over bridges and around an open field perfect for flying kites. It is a nice place to go for a walk, or a bicycle ride, although the summer here is too hot to be outdoors except early in the morning or after sundown.

Yesterday we rose early and rode our bicycles down to the park. The air was still cool in the shade, but the sun was up and it would be hot before long. As we turned onto the path, I spotted a large turtle, a red-eared slider, in the grass near the path. It was a good fifteen meters from the water, which was strange; when the turtles pull themselves up onto the bank to bask in the sun, they usually stay right at the water’s edge, ready to slide back into the lake at the first sign of someone approaching. Why was this turtle so far from the safety of its habitat?


I stopped and signaled the boys to come slowly and quietly. As we watched, the red-eared slider dug into the ground with its hind legs and began laying a clutch of eggs! Slowly it began to scrape the soil back into the hole to cover them up.

Turtles, like all reptiles, are exothermic (or “cold-blooded”); they depend on the environment to warm or cool their bodies. If a turtle lying on the shore gets too hot, it goes back into the water to cool its body. But this turtle was a long way from the water (at least, for a turtle!) As I watched the turtle covering its eggs, I began to worry that it would overheat. The spot it had picked to dig its nest had been in the shade when it began digging, but now the sun beat down directly on the turtle’s shell. I wondered how long it would take for the turtle to finish covering its eggs and drag itself back down to the lake.

I need not have worried. A few minutes later, the nest covered and nearly invisible, Mother Red-Ear was on her way back to the cool water. She stopped in the shade of a hackberry tree to rest beside a fallen branch. Soon she was back in the water.


Andres asked, “When the baby turtles hatch, how will they find the lake? What if they go up onto the road instead, or get lost in the park?”

The short answer is that aquatic turtles hatch with the instinct to go straight for the water. They don’t know where the water is, or even what it is; they have no experience at all, yet they all head for the water as quickly as a baby turtle can (which is quite a bit faster than the adults, on land anyway). Instinct drives them; they can’t help it. The reason for this instinct is obvious: the ones, long ago, who went in any direction other than the water failed to survive, and never grew up to pass that trait on to their offspring. Today, all aquatic turtles are descended from turtles who survived by seeking the water as soon as they hatched, and so all aquatic turtles have that instinct.

So turtles go to water because of survival instinct. But what makes a hatchling turtle move in the right direction? There must be something a baby turtle can sense in order to trigger the instinct. Since gravity makes water lie in the lowest part of any area, it makes sense to think that newly hatched turtles would follow the slope of a beach or lakeshore down to the water. Another possibility is that the mother turtle leaves a scent trail for the hatchlings to follow, but since the eggs take two to three months to hatch, it seems unlikely that there would be much of a scent left to detect. Finally, researchers have observed that baby sea turtles can become confused by electric lights near the beach, becoming attracted to the lights instead of the water. On a beach with no electric lights, the brightest place is the water because it reflects moonlight or starlight from the sky. Maybe turtle hatchlings find their way by the difference in brightness between land and water.


Our turtle’s eggs should hatch towards the end of summer. We will be watching for the baby turtles to crawl down to the lake. One way or another, they will find the way!

Happy Earth Day!

Elsa asks: Is the Earth alive?

That kind of depends upon what you mean by “alive”!

Our planet is not itself an organism like a plant or an animal. But it had a beginning (about 4..5 billion years ago by our best estimate), and since then it has been active and changing, both inside and on the surface. Earth’s core generates its own heat, and the motion of the boiling rock in the mantle (the middle layer of the Earth) is what causes the continents to shift and move across the surface of the planet. Landmasses rise above the ocean and sink again; mountain ranges are thrust towards the sky and worn slowly down by the weathering effects of wind and water. Glaciers advance and retreat, and the balance of gases in the atmosphere responds to the changes in plant and animal life. Planet Earth is a complex and dynamic system that changes over time, which certainly sounds more like life than otherwise.

One characteristic of living things is that they reproduce. What would you call it if we sent a colony of humans with Earth plants, animals, fungi, and bacteria to other worlds, to grow and live like we do on Earth? There will be such a colony on Mars within a few decades at most; more distant worlds will be harder to reach, but consider: only seventy years ago, most respected scientists believed it was impossible to send people to the moon. They were not only wrong, they themselves lived to see it happen. “Hard to reach” only makes humans jump higher. When Earth organisms have spread to other planets, is that not a kind of reproduction for our own planet Earth?

Someday there will be an end for Earth. In about 5 billion years, the Sun will grow into a red giant star and swallow up the inner planets (including Earth). So you could say that Earth has a lifespan, like other living things. That brings us to the reason I wanted to answer Elsa’s question on Earth Day.

Some people say that we are destroying our planet with the pollution from our factories, vehicles, and power plants. This is not really true. We can pollute the Earth so badly that it will become toxic and unable to sustain human life. That would be the end of us humans. But it would not be the end of Earth – some form of life would survive, just like it always has. When we care for the Earth, we are caring for ourselves first!

The first Earth Day was on April 22, 1970; today is the 44th Earth Day! Since 1970, we have been celebrating Earth as something that we should respect and treat with care. As a result, our air is cleaner than it was 44 years ago. We have passed laws that make individuals and corporations more responsible than before. There is still much to be done; many people still do not understand that keeping the environment healthy and clean is more than just the right thing to do: it is a matter of our own survival.

We can make a difference every day, not only once a year. By conserving resources, recycling, and always trying to find ways to work smarter and cleaner, we can help return our Planet Earth to the beautiful place it was before we started to change it. Future generations will thank us.

Happy Earth Day!