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!

Back to School

It’s the beginning of another another academic year. In addition to teaching online courses, I am once again teaching Thermodynamics at Anderson University. I love teaching thermodynamics, because it is a difficult subject, but it explains so much about creation. Unfortunately, many scientists and even some engineers (like Bill Nye) don’t understand it. I hope that my students walk away with a solid grasp of the subject.

Of course, teaching at the university on top of my online courses will make me a lot busier than I should be, so I am not sure how much time I will have for blogging. I will try to write at least once a week, but we will see how that goes. For now, I hope that you enjoy this video, which is the demonstration I did for the first day of class. A variation of the first part of the demo (the aluminum foil heat engine) is in the last book of my elementary science series, Science in the Industrial Age. Students make the engine when they learn about Sadi Carnot, the father of thermodynamics.

Cool “New” Unexplained Phenomenon

An example of a STEVE event. This one happened on August 17, 2015. (click for credit)

Have you met STEVE? It’s a strange event that has been photographed by several people who spend a lot of time photographing auroras. One of them (Chris Ratzlaff) suggested the name “Steve,” which was inspired by the animated movie Over the Hedge. Apparently, one of the characters in the movie named something he didn’t understand “Steve.” When the scientific community began studying this phenomenon, they kept the name but made it more “scientific.” They called it STEVE for “Strong Thermal Emission Velocity Enhancement.”

Since STEVE events happen where auroras are found, it is reasonable to think that they are related to auroras in some way. However, auroras are visible every night when you are at high latitudes and the viewing conditions are favorable. By contrast, STEVE events are visible only a few days each year, at least according to the photographers who have documented them. Also, auroras produce a glow that spreads wide throughout the night sky, while STEVE events produce ribbons of light.

So what causes these events? Currently, scientists can’t say. The initial study said they might be similar to auroras, which are caused by high-energy charged particles that have been trapped by earth’s magnetic field interacting with molecules in the upper atmosphere. This interaction gives the molecules excess energy, and they emit that energy in the form of visible light, mostly reds, greens, and blues. Scientists looked at satellite imagery that was taken during a documented STEVE event, and they did see charged particles moving at high speeds through the appropriate region of the atmosphere, but they couldn’t say for sure that they were related to the event.

Now, some of the authors of that study have published an analysis that indicates STEVE events are not very similar to auroras. They looked at imagery from the National Oceanic and Atmospheric Administration’s polar orbiting satellites that happened to be over a documented STEVE event on March 28, 2008. It was in the perfect position to see if high-energy charged particles were interacting with the upper atmosphere during the event, and it saw none.

As a result, there is currently no explanation for what causes STEVE events. I look forward to seeing where the research goes on this!

The Global Warming Alarmists Were Wrong (Again)

The white corals in the picture have bleached (click for credit)

Corals are amazing animals that form reefs which are teeming with life. They eat things that are floating in the water around them, but they also have a mutualistic relationship with algae called “zooxanthellae.” The corals provide the algae with housing, and in exchange, the algae give the corals chemicals they need. It’s a wonderful system that allows both species to flourish.

However, there are times when this system breaks down. When corals become “stressed” (usually by a sudden change in temperature, the intensity of sunlight, pollution levels, etc.), the algae are expelled from the corals. The details of this process are still a mystery, but it usually causes the corals to turn white, as shown in the picture above. Because of that, this process is often called bleaching.

Earlier this year, The New York Times published an article entitled, Global Warming’s Toll on Coral Reefs: As if They’re ‘Ravaged by War.’ It stated:

Large-scale coral bleaching events, in which reefs become extremely fragile, were virtually unheard-of before the 1980s.

That’s the typical “party line” when it comes to those who don’t want to study the issue of global warming seriously. Something bad is happening now, it hardly ever happened in the past, and if we don’t do something about it soon, we are all going to die. Not surprisingly, it just isn’t true.

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Clouds that “Glow” in Twilight are Becoming More Common

Noctilucent clouds over Uppsala, Sweden (click for credit)

The picture above shows a phenomenon that can be seen during the summer by people who live at latitudes of 50-65 degrees. They are called noctilucent (“night shining”) clouds, and they appear to glow in the twilight sky. They aren’t actually glowing, and they aren’t really clouds, either. Instead, they are bands of ice crystals that are way above the clouds, in an upper part of the atmosphere called the mesosphere. There is very little water in the mesosphere, and it is extremely cold there. When conditions are right, however, what little water that exists there can freeze into tiny ice crystals, forming short-lived “clouds.”

Why do they appear to glow? Well, at twilight, the sun is below the curve of the earth, so you can’t see it directly. However, if you were up higher, you could still see it. Indeed, this video shows a drone observing the sunset at a height of 80 feet and then rising to 400 feet to see the sun set again. So even though you can’t see the sun once it sets, higher altitudes still “see” it. That means the sun’s light is still shining brightly on things that are high in the sky, including the ice crystals. Some of that light scatters off the crystals and heads to the earth. If you are at the right place on the earth and it is dark enough, you can see that light, and it looks like the light is coming from the “clouds” themselves. Here is an excellent time-lapse series that shows both noctilucent clouds and an aurora.

Why am I blogging about this phenomenon? Because this year has been an unusually good year for seeing it. Indeed, reports of these “glowing clouds” have tripled this year compared to last year. What’s causing it? According to Dr. Lynn Harvey of Colorado’s Laboratory for Atmospheric and Space Physics, it’s because there is an unusual amount of water in the mesosphere this year. It is also a bit colder than normal. Combine those two effects and you have more ice crystals and therefore more noctilucent clouds.

Why is it wetter and colder this year in the mesosphere? We don’t really know. In fact, noctilucent clouds are a bit of a mystery in general, since they were first reported in the summer of 1885. Whether that means they just started forming then or just happened to be noticed then, we don’t know. However, most other striking atmospheric phenomena had been observed much earlier. Auroras, for example, were reported in ancient china and were named by Galileo in 1619. It’s hard to believe that a similar atmospheric phenomenon that can be seen at the same latitudes existed but remained unnoticed until 1885.

Of course, unlike auroras, noctilucent clouds are rare and short-lived. After all, they occur only in the summer and, in order to see them, it needs to be pretty dark, since sunlight overwhelms the small amount of light coming from the ice crystals. Thus, the sun has to be below the curve of the earth for the observer. However, once the sun is well below the curve of the earth, it no longer shines on the ice crystals in the mesosphere above the observer. This fact might have made them less likely to be observed and, even when they were observed, less likely to be believed, since they would “disappear” after a while.

So it may be that noctilucent clouds clouds are a fairly recent phenomenon caused by human activity, and it may be that whatever human activity is causing them is increasing their frequency. Of course, it may also be a natural phenomenon that ebbs and flows over time. We just don’t know. That’s the great thing about science. There always seem to be more questions than answers!

LED Lights Might Pose A Hazard for Vision

Wavelengths coming from various light sources (image modified from the Tosini 2016 article linked below)

A very good friend showed me an article from the University of Toledo. It reports on a study that demonstrates how blue light might be damaging to the light-sensing cells found in your eye. I didn’t know anything about this, so I decided to look into the research that has been done on the effects of blue light on vision. I found this excellent review article, which discusses what has been figured out so far. The short answer is that we don’t know anything for certain, but there is some evidence that long-term, chronic exposure to significant amounts of blue light could be damaging to your eyes.

Several animal studies have shown that exposure to blue light can increase the animal’s risk of age-related macular degeneration (AMD) and other eye problems. However, studies on people haven’t been clear. Some studies have shown a relationship between long-term exposure to the sun’s light and AMD, and it is assumed that the blue light given out by the sun is the culprit. However, a case-controlled study in Australia indicated that it might not be exposure to the sun’s light that is causing the relationship. It indicates that sensitivity to glare and difficulty developing a tan are the actual indicators of higher AMD risk, and studies that show a relationship between the sun’s light and AMD might not be controlling properly for those variables.

The study that was discussed in the University of Toledo article linked above didn’t assess the damage blue light causes to human eyes. Instead, the authors assessed the damage on human cells. However, they didn’t use actual light-sensing cells from a human eye, because that’s not possible. They used HeLa cells, which are a line of cells that came from cancerous tissue taken from a woman named Henrietta Lacks more than 65 years ago. The cells continue to reproduce to this day, so this line of cells is often referred to as “immortal.” The story behind the acquisition of the cells is the topic of a very sad and interesting book as well as a pretty lousy movie.

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Pre-Kindergarten Education Might Cause Long-Term Disadvantages!

Many educators (and even more politicians) think that getting children into school early produces great educational benefits. However, the data suggest otherwise. Perhaps the most famous results come from the Head Start study by Puma and others. It found that while the Head Start preschool program produced some short-term benefits, those benefits disappeared for most of the students by third grade. Overall, then, the Head Start program had no lasting effect for most students.

To me, this makes perfect sense. After all, if you give a student some education before most of his or her peers, the student will be “ahead” when he or she starts kindergarten. However, since all the students are following the same curriculum, this “head start” doesn’t do much good, because in the end, the students with the advantage are held back. Rather than using the advantage to push them to learn even more, they are taught the same things that are being taught to the other children. As a result, the only real advantage is that the learning is easier at first. Also, since they have already been “socialized” into the group-learning mode used by schools, they don’t have to adjust to it. Once the others have adjusted, however, that benefit also goes away.

My publisher recently made me aware of another study that comes to an even less-promising conclusion. This study comes from the Tennessee Voluntary Pre-K program, a state-run pre-kindergarten (pre-K) program that focuses on children at risk. The authors followed a total of 2,990 students from kindergarten through 3rd grade, and the results weren’t in line with the expectations of the educators and politicians that promote pre-K education.

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