Category: Answered Questions

Did This Bird Go Extinct and Re-Evolve? I Doubt It.

A flightless Railbird on the Aldabra atoll in the Indian Ocean (click for credit)

Over the past few days, several people have sent me articles like this one, which makes a rather fantastic claim:

The Aldabra white-throated rail bird was declared extinct, a victim of rising sea levels almost 100,000 years ago.

However, the flightless brown bird has recently been spotted – leaving scientists scratching their heads as to how – and why – the species has come back to life.

What do you conclude from reading that? The article seems to be saying that no one had ever seen this bird before; it was only known from the fossil record. Now, however, living versions of it have been seen, and how they came back from extinction is a mystery. Unfortunately, like many “science news” stories, this one distorts the science to the point that it is deceptive and misleading.

The science that is being distorted comes from a study published last year. A responsible article that describes the study can be found here. While the study and the responsible article don’t distort the science, I do think the conclusion that they draw is not the only one consistent with the data.

Let’s start with the bird that is being discussed. It’s the Aldabra white-throated rail, whose scientific name is Dryolimnas [cuvieri] aldabranus. It lives on the Aldabra atoll in the Indian Ocean and is nearly identical to white-throated rails (Dryolimnas cuvieri) found in other parts of the world, like Madagascar. However, the ones on the Aldabra atoll cannot fly, while the others can. As a result, the flightless birds on the atoll are considered a subspecies of the version that can fly.

While we cannot say for sure, the generally-accepted origin story for the Aldabra white-throated rail is that normal white-throated rails landed on the atoll, and since there were no predators there, they stayed. Since they didn’t need to fly anymore, they evolved into flightless birds over several generations. This makes sense, because when a population of organisms doesn’t need a particular biological trait, mutations can degrade those traits without affecting survivability. In addition, DNA is so incredibly well-designed that over the course of generations, it can “turn off” genes that are no longer used in order to save energy. As a result, it makes sense that these flightless birds are descendants from birds that could originally fly.

Why do these articles discuss the birds being extinct at one point? Because the authors of the scientific study looked at the fossil record of the atoll. Using scientifically-irresponisble dating methods, they came to the conclusion that the atoll was completely underwater about 140,000 years ago. When they looked at fossils they interpreted to be older than 140,000 years, they found two bones that seem identical to the corresponding bones in the Aldabra white-throated rails that currently live on the atoll. Thus, they conclude that these flightless birds lived on the atoll before it went completely underwater.

Well, since the birds couldn’t fly, the authors assume that they all died when the atoll was underwater. However, in fossils that they interpret as being deposited after ocean levels decreased and the atoll was no longer underwater, they found another bone that looks similar to the corresponding bones in white-throated rails that can fly. However, it is heavier and more robust than what is found in those birds, but still lighter than what is found in the flightless Aldabra white-throated rails. In other words, it seems to be “in between” the bone of a normal white-throated rail and a flightless white-throated rail. To them, that gives “irrefutable evidence” (their words) that the Aldabra white-throated rails evolved twice: once before the atoll went underwater, and once after.

While their interpretation of the evidence makes sense and is consistent with all the known data, their case is certainly not “irrefutable.” First, you have to assume that they are interpreting the fossil record correctly. There is a lot of evidence to indicate the earth isn’t anywhere close to 140,000 years old, and if that evidence is correct, then their entire explanation is wrong. Also, even if the earth is as old as these scientists want to believe, the authors’ explanation is not the only one consistent with the data. We know that flightless animals can move from place to place on floating mats of vegetation. This is called “rafting,” and it is used by both evolutionists and creationists to explain the worldwide distribution of certain animals. If the atoll flooded like the authors think, the flightless birds could have survived by rafting. What about that one bone that is “in between” the two subspecies? There are natural variations in all bones. A “more robust” bone from a normal white-throated rail can be explained by natural variation within a population of normal white-throated rails.

The main reason I am writing about this is not to argue with the authors. It’s to point out the deceptiveness of articles like the one I quoted at the beginning of the post. As I have said many times before, do not believe the things you read in the popular press when it comes to science. Most “science journalists” are profoundly ill-equipped to understand science, and usually quite poor journalists as well.

More Thoughts on the New Coronavirus

An infographic adapted from one produced by the CDC (click for larger version)

A few readers have sent me questions regarding the coronavirus that is spreading across the world, so I thought I would make a post answering those questions and providing some resources you can use to deal with the issue. Please note, however, that I am neither a medical doctor nor a biologist. As a result, I don’t claim any expertise on the matter. However, there are some misconceptions about the virus that are easily cleared up, and there are some facts that anyone who can understand the scientific literature should share.

First, a few facts. The term “coronavirus” refers to a very large group of viruses that circulate mostly among mammals and birds. However, some are able to infect people. Most coronaviruses that infect people produce mild illnesses, but some (like this one) produce potentially fatal ones. The coronavirus that is in the news right now is one that has not been seen before. This is not unusual. When an animal is infected with two different versions of the coronavirus, they can mix together, producing a new (usually called “novel”) coronavirus. This particular novel coronavirus has been charmingly named SARS-CoV-2, and it causes the disease referred to as COVID-19. Because of that, it is sometimes referred to as the “COVID-19 virus.”

The reason it has been given the name SARS-CoV-2 is that its genetic sequences indicate it is very similar to the virus that caused the SARS outbreak of 2003. Based on that sequence, it is thought that the virus originated in bats, but it might have passed through another animal (possibly a scaly anteater) before infecting people. Most importantly, there is strong evidence against the idea that it was genetically engineered. This is because the way it infects people is quite different from what would have been predicted given our current knowledge about these viruses. In other words, it is very hard to believe that anyone knowledgable enough to engineer a virus would purposefully make the genetic sequences that end up allowing the virus to be so good at infecting people.

The illness caused by this virus is flu-like, but it is much more serious than the flu. The death rate caused by the flu changes from year-to-year, depending on the strains that circulate. However, on average, the flu has a death rate of about 0.1%. That means for every 1,000 people who get the flu, 1 will die. Even though that is a low death rate, a lot of people get the flu. As a result, millions of people die from the flu every year. We don’t know the death rate for this new virus, since we don’t really know how many people have actually been infected, but the best estimate so far is that the death rate is about 2%. That means this virus is thought to be 20 times more deadly than the flu virus.

Second, the resources. The infographic above has been adapted from one that was produced by the CDC. The university at which I teach has asked all its professors to post this electronically as well as wherever students might be found. It is basic, but nevertheless, it does contain some helpful information. This link will take you to the latest information regarding where the virus has been detected, how many people have been infected, and how many people have died.

In general, the best way to avoid being infected by this virus is to avoid other people and avoid going to places where it has been found. The virus spreads most effectively when an infected person is within a few feet of an uninfected person. However, it might also be transferred by surfaces. If someone sneezes on a surface and someone else touches that surface, the virus can be transferred to the hand. Then, if that person touches his or her mouth, nose, or eyes, it is possible for the virus to begin an infection. Thus, you need to wash your hands a lot and avoid touching your eyes, nose, and mouth in between washings.

The most important thing to remember is that while the illness caused by this virus has a death rate that is thought to be about 2% on average, it is significantly higher for elderly people, people who are already sick with something else, and people with weakened immune systems. Thus, if you show any of the signs of the illness (fever, cough, shortness of breath) and think you might have been in contact with someone who has the virus, you should seek medical help.

While there are several groups working on a vaccine to prevent the spread of the virus, the earliest a vaccine could possibly be ready would be at least a year from now. My guess, given that I am anything but an expert about these things, is that it will not be needed. The disease seems to have already plateaued in China, and I expect other countries to be a bit better at reducing the spread. Thus, I expect that the spread of the disease will slow down significantly before a vaccine can be approved for use. I could easily be wrong about that, however.

How Can a Planet Orbit Two Stars?

An artist’s interpretation of the planet TOI 1338b, which orbits a binary star system. The planet is on the left. The two stars are the two white spheres. (NASA image)

If you haven’t seen it, there is a viral story about a high school student, Wolf Cukier, who made a significant discovery. During a summer internship, he was looking through data that had already been flagged as coming from binary star systems. In these systems, two stars orbit one another. While this may sound unusual, most stars in the universe (as far as we can tell, anyway) are a part of a system in which two or more stars orbit one another. Solitary stars like our sun are the exception, not the rule.

In most binary star systems, one star is much brighter than the other. As a result, if earth’s orbit is aligned with the orbital paths of the two stars in a binary star system, when the dimmer star passes between earth and the brighter star, the light we get from that star system gets dimmer. This is called an eclipsing binary. The data that Wolf Cukier was studying had already been noted as representing eclipsing binaries, but Wolf noticed another periodic dimming in the light coming from a binary star system charmingly named “TOI 1338.” The dimming was weaker than the dimming seen from the eclipsing binary, but it was regular. It was determined that this weak dimming was the result of a planet coming between earth and the brighter star in the binary system. In other words, this young man had found a planet orbiting two stars! Such planets are rare, but not unheard of. There were seven such planets confirmed before this one, but this is the first one discovered using this particular telescope, which is called TESS.

If you can’t quite visualize what is going on here, NASA has made a helpful animation, which I have included below. As you can see from the animation, when the dimmer star in the system passes between earth and the brighter star, the amount of light earth receives from the system decreases a lot. When the planet comes between earth and the brighter star, it dims a little.

The student and several scientists have co-authored a paper that has been submitted for publication. Years ago, I had a high school student co-author a scientific paper with me because of a discovery she made under my supervision, and it was very exciting. I hope that their paper gets published as well!

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When Is a Person Actually Dead?

A student recently sent me an article from Live Science that reports on a man who was declared dead by three doctors. Four hours later, as he was being prepped for an autopsy (the marks to guide the autopsy had already been put on him), he started snoring! As of the time the article was written, he was alive and in the intensive care unit of a hospital. The student asked how such a thing could happen. Was it incompetence on the part of the doctors, or is it difficult to tell whether or not a person is dead? I told the student that while I couldn’t address the details of this particular case since I wasn’t involved, I could tell him that there have been cases over the years where the experts were convinced that a person was dead when, in fact, that person wasn’t.

I first heard this kind of story when I was preparing for a talk about miracles. I ran across the case of Emma Brady. She had been declared dead after exhibiting no vital signs. She was placed in a body bag and taken to the morgue. When her children arrived about an hour later to say their goodbyes, they found her gasping for air. The administrator of the hospital said that after the family told a nurse about what they had seen:

Miraculously, the patient exhibited vital signs that were absent previously.

Over the years, I have kept my eye out for stories like this, and while they are rare, they are most certainly not unheard of.

Consider, for example, the story of Steven Thorpe. At age 17, he was in a tragic accident that killed one of the other occupants of the automobile. He was put in a medically-induced coma, and a team of four physicians told his parents that he was brain dead. They suggested that his organs be donated to help others. However, the parents brought in an additional doctor (a neurologist), who demonstrated faint brain activity. The doctors at the hospital agreed to bring him out of the medically-induced coma, and Thorpe recovered. He left the hospital five days later and at the time the article was published, he was alive and well.

Once again, while these stories seem rare, they are not unheard of. In 2008, Zack Dunlap was in an automobile accident and was declared dead 36 hours later. However, he wasn’t dead. In fact, he says that he actually heard his doctors saying that he was dead. The hospital made plans to harvest his organs, since his driver’s license said that he was an organ donor. However, as his family was saying goodbye, one of his cousins (a nurse) decided to pull out his pocket knife, hold Zack’s foot, and scrape the knife against it. Zack pulled his own foot out of his cousin’s hand. The family took it as a sign of life, and they argued that the hospital should treat Zack as if he were alive. He ended up making a full recovery.

The bottom line is that while we have amazing technology and a lot of knowledge about human anatomy and physiology, there are limits to what we can detect and what we can conclude. While it is sometimes very obvious that someone is dead, there are other times when even the experts can be fooled. That’s something all of us need to keep in mind when we deal with life and death issues.

No, It’s Not a Picture of an Atom

When I wrote the first edition of my high school chemistry textbook (back in 1994), I discussed the impossibility of seeing atoms. Atoms aren’t just small; they are simply too small to be seen, even with the most powerful microscope. That’s because in order for us to see something, light must bounce off it and enter our eyes. Cells on our retina detect that light, send nerve signals to our brain, and our brain interprets the signals to form an image. Since atoms are roughly 1,000 times smaller than the smallest wavelength of visible light, there is no way for light to bounce off a single atom. As a result, we will never be able to see individual atoms, no matter how powerful a microscope we use.

I said that every year to every general chemistry class I taught at the university level, and no one ever questioned my assertion. But homeschoolers think more critically than most students, so the very first year my chemistry course was published, I got a FAX (yes, a FAX) from a student questioning my statement. The student showed me an image like the one below, which was taken with a scanning tunneling electron microscope at IBM. She asked if it wasn’t a picture of individual atoms:

An image of the surface of nickel, as produced by a scanning tunneling electron microscope (click for source)

While the image is generally presented as a “picture” of nickel atoms, it is not. It is a graph that represents data that have been processed through a series of equations which govern the behavior of electrons traveling at high speeds. The equations depend on multiple theories, including special relativity and quantum mechanics. I am pretty confident that those theories are mostly true, so I am pretty confident that this is a realistic representation of atoms on the surface of a nickel foil. However, it is not a picture. Light was not used (high-energy electrons were used), and the image is not a direct representation of the nickel surface. It is a direct representation of data that have been processed through mathematical equations that come from several theories.

Recently, I got a question from a teacher who is using my new chemistry course. A student brought him an article that says scientists have been able to take a picture of a single strontium atom. I told the teacher why it is not a picture of a strontium atom, and then over the weekend, I got the same question on my Facebook page. As a result, I decided to write a quick article (well, as quick an article as I can write) about it.

This is definitely a picture, as it is the result of directly detecting light. And, that light is coming from a single atom. That’s the remarkable aspect of the photograph. Because atoms are so small, it is very hard to isolate a single one, but the experimenter who took the picture was able to do just that. However, it is not a picture of the atom. It is a picture of the visible light that the atom is emitting as a result of being excited. When atoms are excited, they must get rid of that excess energy, and one way they can do that is to emit light. The strontium atom is emitting visible light, which is why a picture of it could be taken.

Once again, however, this is not a picture of the atom; it is a picture of visible light being emitted by the atom. After all, the picture shows that the light is purple. If this were a picture of a strontium atom, it would mean that strontium atoms are purple. However, atoms have no color, because they are smaller than the smallest wavelength of visible light.

If you think I am just being pedantic here, consider the picture below:

Tubes of neon atoms emitting light as a result of being excited by electricity. (click for credit)

Each tube in the picture contains neon gas, and electricity is being passed through the gas, giving the atoms extra energy. To release that energy, they emit light, and the visible wavelengths that are emitted produce the orange color that you see in the picture. Are you seeing all the individual neon atoms in those tubes? Of course not. You are seeing the light that those excited neon atoms are emitting.

The “picture” of the strontium atom is the same thing, except that there is only one atom emitting light, while there are roughly 100,000,000,000,000,000,000,000 neon atoms emitting light in the picture above.

Why Do I Include God in My Science Texts?

13th-century illumination from the French Bible Moralisée, depicting Christ (who is God) creating the World.
I was asked that question a couple of days ago, but it wasn’t the first time. Over the years, several people have asked me why I write about God in my science textbooks. After all, science is about facts, while belief in God is about faith. Science doesn’t belong in religious texts, and God doesn’t belong in science texts. That may sound reasonable in today’s world, but it is simply dead wrong. In addition, it demonstrates a shocking level of ignorance about the history of science. Nevertheless, it is a good question, and it deserves a detailed answer.

First, there is an obvious philosophical reason: God is the source of all that science studies, so it only makes sense to discuss Him in the context of studying His creation. Consider, for example, teaching a course on U.S. Law. Would you try to teach it without referring to the U.S. Constitution? Perhaps. Maybe there are law professors who do just that, but for me, I can’t imagine discussing U.S. law without discussing the source from which it comes. In the same way, I find it pointless to discuss science without discussing its source.

Second, there are practical reasons to discuss God while teaching students about science. If we emphasize the fact that the things we study as scientists are designed, we give students a superior way in which to view the natural world. Those who want to reject the idea of a Creator God will try to convince students that this world was “thrown together” by random chance. As a result, students get the idea that creation is full of shabby constructions. Of course, nothing could be further from the truth. The designs found in the natural world make our best technology look like garbage. This has led one desperate atheist to write:1

Biology is the study of complicated things that give the appearance of having been designed for a purpose.

Of course, a more reasonable evaluation of the data leads us to the conclusion that biology is the study of things that have been designed for a purpose.

This is very important, because when we understand that biology is the study of designed things, we don’t fall prey to misconceptions that hold back the progress of science. How many lives have been wasted because scientists looked at the primary cilium as a evolutionary vestige rather than an antenna designed to receive signals? How long did scientists delay a more detailed understanding of genetics because of the nonsensical notion of “junk DNA”? How many people needlessly suffer relapses of intestinal bacterial infections because of the silly idea that the appendix is a vestigial organ? A scientist who understands that the natural world is designed is simply better able to interpret what he or she is studying, since it is the more realistic view.

Finally, there is a spiritual reason to include God in science. As Nobel laureate Dr. Arthur Leonard Schawlow once put it:2

But the context of religion is a great background for doing science. In the words of Psalm 19, “The heavens declare the glory of God and the firmament showeth his handiwork.” Thus scientific research is a worshipful act, in that it reveals more of the wonders of God’s creation.

Ever since I became a Christian, science has been a worshipful act for me. There is no way I could write about this worshipful act without including the One who is being worshipped!

REFERENCES

1. Dawkins, R., The Blind Watchmaker, W.W. Norton & Company, New York, USA, p. 1, 1986.
Return to Text

2. Cosmos, Bios, Theos, Henry Margenau and Roy Abraham Varghese, ed., Open Court Publishing 1992, p. 106.
Return to Text

Large Study Indicates Genetics Has Little Influence on Sexual Orientation

I don’t normally write on topics like this, because studying human behavior is a tricky subject. There are all sorts of different explanations for a given behavioral characteristic in people, and trying to isolate a specific cause is difficult, to say the least. However, there has been a lot of news about the recent study that concluded there is “no gay gene,” and I have gotten several questions about it. As a result, I decided to read the study and share my thoughts.

First of all, it’s not surprising that there is no gay gene. In fact, researchers have said that for years. If there were a single gene that heavily influenced whether or not a person is homosexual, it would have been easy to find and discovered years ago. Also, even something as simple as the color of your eyes is governed by at least eight different genes. Thus, to think that something as complex as sexual behavior is governed by one gene is naive at best. So that specific result of the study is not even interesting, much less newsworthy. What makes the study newsworthy is its size, its scope, and the fact that its conclusions are very weak.

The study is massive in two ways. First, the main study looked at 477,522 individuals, but then it repeated the study using three smaller datasets that were composed of 15,142 individuals. Whenever you study people, the more people you have, the less uncertain your results will be. Thus, the sheer number of individuals in the study makes it important. Second, the study compared the entire genomes of the individuals. In other words, they looked at all the DNA found in the nucleus of the individuals’ cells. That’s a massive amount of data for a massive number of people!

What it tried to do is compare single nucleotide polymorphisms (SNPs) among the individuals to see if they could be correlated with sexual behavior. If you aren’t familiar with the term, SNPs are the most common variation between sets of human DNA. Genetic information comes in sequences of DNA building blocks called nucleotide bases. There are roughly three billion nucleotide bases in one strand of human DNA. An SNP is a change in one of those nucleotide bases.

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There Is Nothing Unusual About the Fires in the Amazon

Fire in the Stanislaus National Forest (not the Amazon region) in 2013 (click for credit)

I had another blog post planned for today, but I decided to put it off because over the weekend, I got three questions regarding the fires in the Amazon. People are concerned, mostly because of irresponsible articles like this one:

Brazil’s Amazon rainforest is burning at a record rate, research center says

It’s the classic example of a story that is technically true but absurdly misleading. Indeed, the National Institute for Space Research has never seen the number of forest fires that it is currently seeing in the Amazon. However, as the article notes, that research program started in 2013. So yes, over the past six years, this is the worst year yet. However, if you just broaden your scope a bit, you will see that there is nothing unusual about this year.

While the National Institute for Space Research has only been collecting data about forest fires since 2013, researchers at the Global Fire Emissions Database have been studying them since 2003. That’s almost three times as long. What do their data tell us? Well, all you have to do is go here. It gives you a handy graph that shows you the total count of fires in the Amazon region by year.

To make it stand out, I thickened the green line, which represents this year. As you can see, this year is pretty much dead center compared to the past 16 years. If you go to the link itself, you can put your cursor over the year listed under the graph, and you can see each year clearly. If you do that, you will see that 2003-2007 were all worse than this year, with 2005 setting the record. The data are actually more detailed than this. You can click on areas of the Amazon region on the left part of the website and see data for each region. If you click on “Amazonas,” for example, you will see that a few days in 2019 did set the record in that region.

It’s probably worth noting that many of these fires are caused by people…deliberately. Natural forest fires don’t happen in the Amazon region very often. Most of the fires are being set to clear land for agriculture, and most of them are not in the heavily-forested regions. Also, while you might be worried about deforestation in general, you needn’t be. The latest research indicates the earth has been getting greener since 1982.

UPDATE (08/27/2019): It does seem that there is something unusual happening in the Amazon right now. According to this source:

…the fires were at average levels through to mid August, and then there was a huge uptick.

Why was that? Seems that it started when the farmers in the state of Para declared a “‘dia do fogo,'” or “day of fire” on August 10th. They said they did this in order to show to Bolsonaro that they want to work and that the only way to clear pastures for them to work was with fire (report in Portuguese here), This was spectacularly “successful” and there was an immediate increase in fires which continued through the following weeks.

So there is unusual fire activity right now – more than the standard land-clearing fires for agricultural use. The added fires are the result of political protests.

How I Address the Age of the Earth in My Courses

My publisher has been getting several questions about how I address the age of the earth in my science courses. This probably stems from the fact that there is a lot of misinformation going through the homeschooling community regarding my position on the issue. I thought I would try to clear things up with a post.

First, my position on the age of the earth hasn’t changed in more than thirty years. I turned from atheism to Christianity in my late high school years, and at that time, I was happy to believe what my teachers told me about the age of the earth. It was more than four billion years old. I was told that we knew this because of radiometric dating methods, which involved studying the relative amounts of radioactive atoms in rocks and fossils. This “fact” of science was later reinforced when I went to university, so I was still happy to believe it.

Then I started my Ph.D. program in nuclear chemistry. I learned about radioactive decay in detail and started doing experiments with nuclear reactions. Most of my work was done at the University of Rochester Nuclear Structure Research Lab, which also had a group that did radiometric dating. I never did any of that work myself, but I watched them do their experiments, asked them questions, listened to their presentations at the lab, etc. Based on what I learned there, I decided that I couldn’t put much faith in the ages given by radiometric dating.

This caused me to question the age of the earth from a scientific perspective. Theologically, I wasn’t committed to any age for the earth. Certainly the most straightforward interpretation of Genesis is that the universe and all it contains was created in six solar days, and that leads to a young-earth view. At the same time, however, there were early church Fathers (as well as ancient Jewish theologians) who didn’t interpret the days in Genesis that way. So I attempted to investigate the subject with an open mind. I found that in my view, science makes a lot more sense if the earth is thousands of years old rather than billions of years old, so I started believing in a young earth. The more I have studied science, the more convinced I have become that the earth is only thousands of years old.

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What Is the Function of a Narwhal’s Tusk?

Three Narwhals swimming close to the surface of the ocean. The lead narwhal’s tusk is easy to see.
(credit: Dr. Kristin Laidre, Polar Science Center, UW NOAA/OAR/OER)

Back in April, I spoke at the Ohio Homeschool Convention. It is part of the Great Homeschool Conventions, at which I have been fortunate to be a regular speaker. This year, the convention graciously allowed me to do my favorite kind of presentation: A Question/Answer Session. I have done them at other conventions (see here, here, and here), and I always enjoy them, usually because I learn something. I open these sessions by simply asking for questions, and I tell the audience that the questions can be about anything. If I can’t answer a question, I am happy say the three words any scientist should be totally comfortable saying, “I don’t know.” I also tell them that if I have to say those words, I will try to find the answer later and post it on my blog.

That’s what happened at the Ohio Homeschool convention. One of the audience members asked me what a narwhal (Monodon monoceros) does with its horn. I had to tell him that I don’t know. I did tell him that it isn’t really a horn. In fact, it is an elongated tooth. I speculated about a couple of possibilities, but I couldn’t say anything for sure. That was a few weeks ago, and I have been pretty busy since then. However, I have wrapped up both the Thermodynamics course I was teaching at Anderson University, and the online classes I have been teaching this year, so I finally got around to investigating narwhals.

The short answer is that we still don’t know what a narwhal does with its tusk. The long answer, however, is much more interesting.

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