Another Failed Evolutionary Prediction

A common fruit fly, Drosophila melanogaster (click for credit)

The acid test of a scientific theory is whether or not it can make testable predictions about things that are not known. If it can’t, it isn’t really a scientific theory. If it can, those predictions should be tested by observation or experiment. If the results of the test confirm the predictions, you can have more faith in the theory. If they do not, you must either alter your theory or abandon it. One of the main reasons I am a creationist is that creationism has made many testable predictions, and many of those predictions have been confirmed. In fact, creationism has a much better track record when it comes to confirmed predictions than does evolution (see here and here).

Recently, I ran across another study that demonstrates another failed prediction of evolutionary theory. It studied the alcohol dehydrogenase protein (ADH) as made by fruit flies. Fruit flies often consume alcohol because they feed on rotting materials, and the ADH they make allows them to do that. How do they make ADH? They have a gene that gives the necessary instructions to the cell. That gene is, in effect, a “recipe” for ADH.

Studies have already shown that the common fruit fly (Drosophila melanogaster) tends to feed on alcohol-rich things (like rotting fruit) more than a similar fruit fly, Drosophila simulans. The evolutionary explanation that has always been given for this fact is that these two fruit flies had a common ancestor, and that ancestor had a gene that made less efficient ADH. As a result, the common ancestor didn’t eat alcohol-rich things.

The evolutionary line that led to the common fruit fly experienced mutations in the ADH gene, and those mutations ended up making the ADH more efficient. Natural selection then caused those fruit flies to survive, because they could now survive by eating a lot of rotting fruit, while the other flies could eat only a little rotting fruit. That process continued over time, eventually leading to the common fruit fly we see today, which eats a lot of rotting fruit. In evolutionary biology lingo, we would say that the common fruit fly underwent “positive selection” in its ADH gene, while the other fruit fly did not.

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The “Axis of Evil” in Astrophysics

The European Space Agency’s image illustrating two things that seem to falsify the cosmological principle. (click for credit)

A couple of days ago, I had a fun conversation with a student regarding astrophysics. He seemed very well-informed on the subject, so I begin using some physics “slang” to help move the conversation along. The student picked up on most of the references, but then we began discussing the cosmological principle, which is an assumption upon which the Big Bang model (and many other models of the universe) depends. It essentially states:

Viewed on a large enough scale, the properties of the universe are the same no matter where you are

The student was aware that most observations have never supported the cosmological principle, but he brought up the Cosmic Microwave Background (CMB), which he seemed to think supports it. I countered by mentioning the “Axis of Evil,” and he seemed to think I was joking. I was surprised that he didn’t get the reference, so I explained it to him. He was shocked that he hadn’t heard of it before, so he suggested that I write a blog post about it.

To understand the “Axis of Evil,” you first have to understand the CMB. When astrophysicists were working on the Big Bang model of the universe, which essentially says that the universe “exploded” into being from nothing, they realized that such an “explosion” would leave behind a signature: microwaves that appear from everywhere in the universe. The predicted details of these microwaves varied from paper to paper, but regardless of the details, everyone agreed that if the Big Bang happened, there should be a “background” of microwaves found everywhere in the universe. That’s what became known as the CMB.

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Does Anybody Really Know How Hot It Is?

Comparison of raw temperature data to the adjusted data for seven stations in New Zealand
(Figure 6.15 from the study being discussed)

Over the past few years, I have written about problems with the data related to global temperature measurements (see here and here). It is very difficult to get a handle on how the planet’s temperature has changed over the past century or so, because the only long-term data we have come from thermometers that are placed at various spots throughout the world. Since 1979, we have much more accurate global temperature data, which come from satellite measurements. However, those satellite measurements are not consistent with the thermometer measurements.

This is an important issue, because climate models (which make projections about future temperatures based on different emission scenarios) are “calibrated” against the known temperature data in an effort to make them more realistic. Since the satellite data have only been collected since 1979, they are rarely used. Instead, the longer temperature record (based on thermometers) is generally preferred. The two commonly-used thermometer records are GISS TEMP (maintained by NASA) and HadCrut4 (maintained by the University of East Anglia and the UK Met Office). Those two data sets are in good agreement with one another, but once again they do not agree with the satellite data.

Are these thermometer data reliable? Based on the PhD thesis of John D. McLean at James Cook University, the answer is “no.” He did what he claims is the first audit of the reliability of the Hadcrut4 data, and he has found 25 areas of concern. I will discuss only three. First, he finds many instances of anomalous data. One station in Colombia, for example, reports that the 1978 average monthly temperatures in April, June, and July were 81.5 oC, 83.4 oC, and 83.4 oC. In case you aren’t familiar with the Celsius temperature scale, that’s about 180 oF. Given that the highest temperature ever recorded on earth was 134 oF, it’s safe to say that the report from Colombia is simply wrong. He lists many other examples of anomalous data that cannot possibly be correct.

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Wind Farms Warm the Planet

A portion of the Gansu Wind Farm in China. It is the largest wind farm in the world. (click for credit)

More than five years ago, I wrote about a study that indicates wind turbines aren’t as “green” as many think. Indeed, it has been estimated that they are responsible for slaughtering more than half a million birds and nearly a million bats each year in the U.S. alone. A new study indicates another unforeseen consequence of wind farms: they actually warm their local area, which ends up warming the planet, at least a bit.

This isn’t a new suggestion. In fact, this recent study is partly a follow-up of a study that was published 14 years ago. In that study, the authors used a fairly simple physical model to indicate that by changing the way air is mixed near the surface of the earth, wind farms increase the temperature in their local area and, in turn, the entire planet. This new study uses a more sophisticated mathematical model, but it also compares the model’s results to warming that has actually been observed and measured near wind farms.

The authors show that their model reproduces the observed warming fairly well, so they use that model to make some estimates. They estimate that if all of the United States’ electrical needs are met with wind power, the wind farms would warm the continental U.S. by 0.24 degrees Celsius. The authors are quick to point out that this is much less than the warming that is supposed to occur as a result of the carbon dioxide produced by coal and gas power. However, it is clearly more than was expected and is at least ten times larger than any warming expected to be produced by meeting the needs of the country with solar power.

Of course, all of these models are far from realistic, because we are ignorant about so much when it comes to the earth’s climate and how various factors affect it. As a result, I take all of these numbers with a grain of salt. The actual fact is that we don’t know the warming that will occur as a result of any energy production source, including coal and gas. However, just as the science behind carbon dioxide trapping heat in the atmosphere is solid, the science behind this paper is solid. The authors demonstrate quite clearly that based on well-known physics, wind farms do warm their local area, and the observational studies they reference and use in their analysis confirm that this warming does, indeed, happen.

So what’s the bottom line? The most important one is the one I brought up in my five-year-old post about wind farms. The environmental effects of energy production aren’t as simple as people make them out to be. Every means of energy production will affect our planet in some way, and unfortunately, in the effort to produce “green” energy, this fact has been overlooked. If we are really interested in caring for our planet, we should not buy into a certain means of energy production (or a certain means of transportation) just because someone has decided it is “green.” Otherwise, we might be replacing a bad system with a worse one!

Directed Evolution Wins Nobel Prize

From left to right: Dr. Frances Arnold, Sir Gregory Winter, Dr. George Smith
(Credits:Beavercheme2, Aga Machaj, Univ. Missouri-Columbia)

Yesterday, the Royal Swedish Academy of Sciences announced that the Nobel Prize in chemistry will be shared among three scientists who all used directed evolution to engineer proteins that solve problems. A reader who saw a news story about the announcement asked me to explain what “directed evolution” means, and I am happy to oblige. In directed evolution, scientists use the concepts of variation and selection to take a molecule that already exists in nature and adapt it to do something that they want it to do. Using a concrete example that comes from the research of Dr. Frances Arnold (one of the recipients) is probably the best way to explain the process.

Dr. Arnold’s lab started with a naturally-occurring enzyme charmingly named P450 BM3. Enzymes speed up specific chemical reactions, and P450 BM3 speeds up the reaction in which an oxygen atom is inserted between a carbon atom and a hydrogen atom in a fatty acid molecule. This is an important step in the process by which a living organism breaks down fatty acid molecules. Dr. Arnold’s lab was interested in doing the same kind of reaction, but on a different type of organic molecule: a small alkane. The enzyme P450 BM3 couldn’t initially do that. However, it could weakly speed up that reaction on large alkanes.

Since the enzyme could at least do that, Dr. Arnold thought that she could “tweak” it until it did exactly what she wanted it to do. However, enzymes are absurdly complicated molecules, and human science isn’t very good at making or understanding them. So she decided to let better organic chemists (bacteria) do the heavy lifting. Her lab took the gene that tells bacteria how to make P450 BM3 and subjected it to mutations. They then saw whether or not the resulting enzyme made by bacteria was any closer to being able to do what they wanted it to do. Maybe it did a better job speeding up the reaction on a large alkane, or maybe it was able to speed up the reaction on a shorter alkane. If that was the case, they saved that gene and allowed it to mutate more, seeing if any more progress could be made. If not, they threw it away and tried again.

This is why the process is called “directed evolution.” Dr. Arnold’s lab induced mutations (which are a source of genetic change in organisms) and then selected any enzyme that ended up being better at what they wanted it to do. With enough of those steps, they were able to get what they wanted: an enzyme that inserted an oxygen atom between a carbon atom and a hydrogen atom in a small alkane. In the end, the process had changed just over 2% of the molecule, but that was enough to change it from an enzyme that acted on fatty acids to one that acted on small alkanes.

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One Common Ediacaran Was Probably an Animal

A fossil similar to the one in which cholesterol remnants were found. (click for credit)

Several years ago, I wrote about the enigmatic fossils found in Ediacaran rock. Most scientists think such rocks are 635-540 million years old, and the fossils found in them have been the source of much controversy. Some paleontologists think they were “primitive” animals, some think they were lichens, some think they were fungi, some think they were giant protozoa, and some think that many of them aren’t even fossils. Well, based on some recent research, one Ediacaran fossil (Dickinsonia – an example is shown above) was most likely an animal.

The research was done by a team of scientists from Australia, Russia, and Germany. They collected Dickinsonia fossils from Ediacaran rock found on a cliff near the White Sea in Russia. This rock is thought to be 558 million years old. They found a thin layer of organic film on top of the fossils, and they chemically analyzed that film. They found cholestane, which is a chemical remnant of cholesterol. It is important to note that they didn’t find cholesterol itself. They found a decay product that indicates the one-time presence of cholesterol.

Why is this important? Cholesterol is a common component of animal cells, but significant amounts of it are not found in lichen, protozoa, or fungi. Thus, the one-time presence of cholesterol indicates that these fossils were animals. But couldn’t the cholestane be contamination? That’s a possibility, so the researchers chemically analyzed the rocks surrounding the fossils. In those rocks, they found little cholestane. Instead, they found the remnants of steroids that are commonly found in algae. So the cholestane is definitely associated with the fossils themselves and is probably not the result of contamination.

If a large number of the Ediacaran fossils end up being classified as animals, I think that will add to the long, long list of problems with flagellate-to-philosopher evolution. Since these fossils are supposed to have come before the better-known fossils found in the Cambrian, they would represent either the animal ancestors of the Cambrian organisms or some evolutionary offshoot that came from those animal ancestors. Either way, evolutionists are now faced with the task of trying to figure out some fairly close evolutionary relationship between the Ediacaran organisms and the Cambrian organisms. Given that these two sets of fossils are so radically different from one another, I suspect that will be a daunting task!

A Failed Test of Fossil Record Interpretation

When you read about earth history in most textbooks, lots of definitive statements are made concerning events that occurred in the distant past. For example, in Biology: How Life Works, Volume 1 (Morris et. al., Macmillan 2014, 2016), students are told:

A giant meteor struck Earth 66 million years ago, causing the extinction of dinosaurs and many other species…Researchers have documented other mass extinctions, but the event that eliminated the dinosaurs appears to be the only one associated with a meteorite impact. (p. 7)

Any unsuspecting student reading those words would think that we know that a mass extinction of dinosaurs occurred 66 million years ago, that it was definitely cause by a meteor impact, and that there have been other mass extinction events as well.

The problem, of course, is that definitive statements like the ones above come from interpretations of the fossil record. The fossil record itself is spotty at best, and the interpretations are based on all sorts of unverifiable assumptions. So the obvious question becomes, “How accurate are those interpretations?” That’s awfully hard to test, since we can’t go back in time and confirm them. However, the great thing about science is that original thinkers can come along and figure out ingenious ways to test what you might think is untestable.

A team of researchers from the Florida Museum of Natural History, the University of Bologna, the University of the Bahamas, and the State University of New York at Geneseo decided to test how well we know things like the mass extinction events discussed in the textbook I just quoted. They took a series of geological samples from the Po Plain in Italy that are supposed to represent what went on over the past 126,000 years. They specifically examined the mollusks in those samples, which leave behind hard shells.

Their test was both simple and brilliant: Imagine that a mass extinction event occurred right after the samples were taken, and all 119 identified species of mollusks that are currently living there had been wiped out. Would this hypothetical mass extinction be properly interpreted from the fossil remains in the geological samples that had been taken? Not surprisingly, the answer was a solid, “No!”

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Are All Animals Really Omnivores?

An alligator eats a pond apple (courtesy of the Everglades NPS)

I was teaching one of my online biology courses yesterday and discussed something virtually every biology student learns: classifying organisms as producers (who make their own food), consumers (who eat other organisms for food), or decomposers (who decompose dead organisms for food). I then mentioned that consumers can be further classified as herbivores (eating only plants), carnivores (eating only animals), or omnivores (eating both plants and animals). I then asked the students how they would classify an alligator. Of course, they classified alligators as carnivores. I then showed them the picture above. That alligator is eating a fruit (a pond apple) on purpose.

It has long been known that alligators and crocodiles ingest plant material, but it was originally thought to be accidental. Perhaps the alligator was biting for a fish, missed, and took in some plant material that was floating in the water. However, recent research shows that in most species, the ingestion is probably not by accident. It is a part of the dietary strategy.

After class, I was looking at the scientific literature and ran across an incredible report about a similar phenomenon in bonnethead sharks. Once again, it has been well known that these sharks ingest seagrass, but it was thought to be accidental. Furthermore, since a carnivore’s digestive system is tuned towards breaking down meat, it was thought that the sharks gained no nutrition from the accidentally-ingested grass. We now know that this is definitely not the case.

The authors of the study fed bonnethead sharks a diet that was mostly seagrass with just a bit of squid. The seagrass had been labeled with a specific isotope of carbon (carbon-13), which makes up only about 1% of naturally-occurring carbon. This allowed the them to identify the chemicals from the seagrass and figure out what happened to them after the seagrass had passed through the sharks. They found that the sharks were actually digesting the seagrass and using it for nutrition. In fact, even though their diet was 90% seagrass, the sharks gained weight! Finally, the authors found that the sharks’ digestive tracts showed the activity of enzymes which are designed to break down plant matter. They write:

We show that a coastal shark is digesting seagrass with at least moderate efficiency, which has ecological implications due to the stabilizing role of omnivory and nutrient transport within fragile seagrass ecosystems.

If sharks and alligators can eat and digest plant matter, probably all animals we think of as carnivores are at least capable of eating and digesting plant material. Combine that with the fact that animals thought to be strict herbivores have been found deliberately eating other animals, and we come to the strong possibility that all animals are really omnivores.

Of course, one “take home” message from all this is that creation is marvelously complex, and our attempts to categorize it are incomplete, at best. However, it also has implications when it comes to the issue of origins. Most young-earth creationists (including myself) think that before the Fall, all animals were herbivores. We also believe in a global Flood, where Noah and his family had to care for different kinds of animals on the ark for a bit more than a year. Some of those animals were carnivores, but they could not have been fed other animals (except perhaps some sea creatures from time to time). Creationists critics often say both situations are impossible, because some carnivores must eat meat, or they will die.

If a species of shark can gain weight on a diet of mostly plants, it is at least conceivable that prior to the Fall and for a year on the ark, the animals that gave rise to the “carnivores” we see today could have lived on a diet of only plants.

Scientists Who Wear Blindfolds

Dr. Peter Atkins is a legend in the chemistry community. He retired from his professorship at Oxford University in 2007, but not after receiving such distinguished awards as the Royal Society of Chemistry’s Meldola Medal and the American Chemical Society’s James T. Grady-James H. Stack Award for Interpreting Chemistry for the Public. In addition to his publications in the scientific literature, he has written several excellent books. When I taught physical chemistry at Ball State University, I used his Physical Chemistry as my text. The chemistry community owes him a great deal.

Even the best of scientists, however, can purposely blindfold themselves when it comes to reality. Dr. Atkins demonstrates this fact with a piece that was published on Aeon. The article’s title says it all:

Why it’s only science that can answer all the big questions

Anyone with a modicum of philosophical knowledge understands how wrong such a statement is, but if you like, you can read this excellent piece written by a serious thinker, Martin Cothran. It shows the folly of Dr. Atkins’s thinking in stark intellectual terms.

While I don’t pretend to be as smart as Dr. Atkins or Mr. Cothran, I would like to add something to the discussion. When I first read Atkins’s piece, I noticed two huge assumptions that the good doctor makes. It’s clear that he either doesn’t know or doesn’t care that he is making them. Either way, that’s bad. Scientists have to recognize and admit the assumptions they are making, or they are like blindfolded men trying to make sense of their surroundings.

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Another Newly-Discovered Feature of the Human Body!

Microscope image showing the tunnels that exist between a mouse’s skull and its brain.
(Fanny Herisson/Center For Systems Biology/Mass. Gen. Hosp., Figure 5a in the paper being discussed)

The human body is truly incredible. It has been so intricately designed that we are still discovering new things inside it, despite the fact that scientists have been studying it in detail for nearly 2,000 years! Just a few months ago, I wrote about the discovery of a previously undetected feature of the human body, and just this month, a team of medical scientists from Massachusetts General Hospital, Harvard University, and Dongguk University (South Korea) have discovered something else: channels that connect the skull directly to the brain!

The authors made this discovery while they were investigating how certain immune responses work in the brains of mice. White blood cells, the cells of the immune system, are produced in bone marrow, a soft tissue found inside some bones. The authors developed a technique to identify white blood cells produced in a leg bone (the tibia) of a mouse and distinguish them from white blood cells produced in the skull of a mouse. They induced a stroke in the mouse to activate the immune response and studied what happened. As expected, white blood cells were sent to the brain, but unexpectedly, most of them came from the skull.

Why was that unexpected? It has always been thought that white blood cells must travel through the circulatory system to get to the brain. As a result, it was assumed that any white blood cells found in the brain should come equally from all parts of the body. The fact that most of the white blood cells came from the skull indicated that there must be some “shortcut” between the brain and the skull, so the researchers used microscopes to look at the inside of the skull and the surface layers of the brain. What they found is shown in the image above.

The darkest splotches in the image are bone from the skull. The skull’s bone marrow is labelled in the figure, as is the top layer of brain tissue (labelled “Brain membrane”). Notice that there are “Channels” which connect the skull’s bone marrow directly to the brain membrane. That’s the shortcut the white blood cells took. They traveled directly from the skull’s bone marrow to the brain, making the immune response more rapid than if the white blood cells had to travel through the circulatory system.

Even though the discovery of these “brain channels” was made in mice, the authors examined skull tissue removed from patients who had been through a neurosurgical procedure. They found similar channels that were roughly five times as large as the ones they saw in the mice. Of course, they couldn’t do similar experiments on people, so they don’t know for certain that the channels serve the same purpose in humans as they do in mice. However, it makes sense that they should.

The human body is so fearfully and wonderfully made (Psalm 139:14), I am sure this isn’t the last new feature to be discovered!