Month: June 2021

About That New “Dragon Man” Fossil….

A fanciful imagining of what the person who left behind the skull being discussed in the article might have might have looked like. (image from the scientific paper)

The media is abuzz with a “new” fossil discovery. Consider, for example, this article, which says:

A new species of ancient human dubbed Homo longi, or “Dragon Man,” could potentially change the way we understand human evolution, scientists said Friday.

A reader asked me to comment on the discovery, which I am happy to do. Please remember, however, I am not a paleontologist nor a biologist, so my comments are clearly from a non-expert position. Nevertheless, I think I can add a bit of perspective that is sadly missing in most discussions of this fossil find.

First, while this fossil is just making the news, it is anything but new. As one of the three scientific papers written about it informs us, the skull was discovered in 1933 by a man who was part of a team constructing a bridge. He hid it in an abandoned well, apparently with the idea to retrieve it later. However, he never did. Three generations later, the family learned about the skull and recovered it. One of the scientists who wrote the papers learned about it and convinced the family to donate the skull to the Geoscience Museum of Hebei GEO University back in 2018.
So what’s “new” isn’t the discovery of the fossil; it’s the analysis contained in the scientific papers.

Of course, one part of the analysis tried to answer the question of how old the skull is. Two different radioactive dating methods were used (comparing the ratio of two thorium isotopes as well as comparing the ratio of one thorium isotope and one uranium isotope). As is typical with radioactive dating, the two different methods didn’t agree with one another, and even the same method gave different ages depending on where the sample was taken from the skull. In the end, the ages based on these analyses ranged from 62±3 thousand years old to 296±8 thousand years old. Based on many factors, the authors said that the youngest this fossil could be was 146,000 years old.

Before I move on, I want to use these data to highlight something I have discussed before. The numbers that follow the “±” sign represent what scientists call error bars. They are supposed to tell you the most likely range over which the measurement can actually fall. When you read “62±3 thousand years old,” that is supposed to mean, “62,000 years is the most likely date, but it could be as low as 59,000 years or as high as 65,000 years.” In fact, the actual date could be lower or higher, but the most likely range is 59,000 years to 65,000 years. Notice, of course, that these error bars are utterly meaningless, since the measurements ranged from 59,000 years old to 304,000 years. This is one of the many problems with radioactive dating. Error bars that are utterly meaningless are constantly reported, giving the illusion of a very precise measurement, when in reality, the measurement is anything but precise!

With the “measured” age of the skull out of the way, let’s discuss the main issue. The scientific papers, as well as the media reports, indicate that this is a new species of human. It doesn’t represent “modern” humans, and it doesn’t represent other known “archaic” humans. There is one big problem with this idea. The paper says that based on the characteristics of this skull, the human it represents is more closely-related to modern humans than is Neanderthal Man. The problem, of course, is that we know Neanderthal Man is fully human, because we know that Neanderthal Man interbred with modern humans. Thus, Neanderthal Man is from the same species as modern man. Since this skull indicates its owner is even more closely related to modern humans, it is a modern human as well.

So while this skull can tell us something about the variety that has existed among humans over the years, it tells us nothing about the “story” of human evolution. It simply represents another variety of human being.

The American Biology Teacher Uses False Statements to Reassure Teachers

When dinosaur fossils like this one are tested, they contain carbon-14 in significant quantities, which is not possible if they are millions of years old.
Quite some time ago, a reader sent me this article from The American Biology Teacher. It attempts to assure biology teachers that the large amounts of carbon-14 found in dinosaur fossils is compatible with the scientifically-irresponsible idea that those fossils are millions of years old. The reader asked me to comment on the article, since I have said several times that carbon-14 in dinosaur bones is a very strong indication that the bones are not millions of years old. The author of this article (Dr. Philip J. Senter), however, is confident that this is not a problem at all. How can he be so confident? Because he seems to believe a lot of false information.

Early on, he makes a statement that indicates he has not studied carbon-14 dating very seriously:

…bone mineral is usually useless for radiocarbon dating, even though the carbonate that bone mineral incorporates during life contains 14C. The uselessness of bone mineral for radiocarbon dating is due to the fact that bone mineral accumulates new 14C after death, yielding a falsely young radiocarbon “age.”

This statement is utterly false, and anyone who knows carbon-14 dating would know that. Hundreds of radiocarbon dates have been published in the scientific literature using bioapatite, a bone mineral. This study examined using bioapatite in carbon-14 dating extensively, comparing it to two other commonly-used substances in carbon-14 dating. It concluded:

Most Holocene samples exhibit reliable 14C ages on the bioapatite fraction. Late Pleistocene samples have shown reliable results even for extremely poorly preserved bone in the case of samples derived from a non-carbonate environment.

The Holocene supposedly dates back to about 11,700 years, while the Pleistocene supposedly goes back to 2.6 million years. “Late Pleistocene” samples, then, would be samples that go back to the limits of carbon-14 dating (about 50,000 years old). Indeed, in that study, one of the samples had a carbon-14 date of 37,000 years old, which is older than most of the dinosaur bones that have been dated with carbon-14. So the idea that minerals from bone are “useless” for carbon-14 dating is demonstrably false.

Dr. Senter tries to back up his statement with a reference, but the reference doesn’t invalidate the use of bioapatite in carbon-14 dating at all. It does indicate that when you compare the date derived from collagen (a non-mineral that is often used in carbon-14 dating) to the date derived from bioapatite, the bioapatite date is often younger. However, the results depend heavily on where the fossil was found. More importantly, we know this has nothing to do with the carbon-14 dates of dinosaur bones, since many dinosaur fossils have been dated using both mineral and non-mineral samples (including collagen), and the ages are similar. In a hadrosaur fossil, for example, bioapatite dated as 25,670 years old, while the collagen dated as 23,170 years old. Note that contrary to the study Senter cites, in this case, the bioapatite age is older than the collagen age.

Senter then tries to explain why dinosaur bones read so young with carbon-14 dating. Most of his argument boil down to the idea that modern carbon has gotten into the fossils, and since the modern carbon is very young, it makes the fossil read young. The problem with that, of course, is that if modern carbon is getting into the fossil from the environment, there must be more contamination near the surface of the fossil and less near the center of the fossil. Thus, the carbon-14 age of the bone should vary depending on where in the bone the sample was taken. However, that’s not what is seen. In this study, Figure 7 has circles around the dates for samples taken from different parts of the same bone. They show very good agreement, indicating that what is being detected is not from contamination.

There is one argument Dr. Senter makes which isn’t about contamination. He says that radioactive materials can be absorbed by a bone, and those radioactive materials can cause nuclear reactions which will add carbon-14 to the bone, making it look young. Once again, he cites studies to support his claim, such as this one, but once again, the studies don’t support his claim. For example, the study I just linked shows how uranium decay can lead to the production of carbon-14, but as anyone who understands nuclear reactions would tell you, the effect is ridiculously small. Indeed, the study shows that nuclear reactions can account for no more than one hundreth (1/100) of the lowest amount of carbon-14 detected in dinosaur bones! Thus, there is no way that nuclear reactions are a viable means of explaining around the carbon-14 found in dinosaur bones.

In the end, then, we see that Dr. Senter must use false information to assure his readers that carbon-14 in dinosaur bones doesn’t invalidate the dogma that they are millions of years old. Unfortunately, since many teachers read the magazine in which his article was published, I am sure that this false information will be spread around, fooling unsuspecting students. Nevertheless, the more this is investigated, the more we will see that it poses a huge problem for those who are committed to believing that dinosaurs lived millions of years ago.

Radioactive Honey

In some regions, the honey is more radioactive than it should be. (click for credit)
Radioactivity is everywhere. You can’t get away from it. Even the foods you eat are radioactive, since the molecules in your food have chains of carbon atoms in them, and some of those carbon atoms are radioactive. However, one of the most radioactive foods is the lowly banana. It contains a lot of potassium, and about 0.01% of that potassium is radioactive, spewing beta particles and gamma rays into the surroundings. In fact, there is an informal radiation unit called the banana equivalent dose, which allows you to get an idea of how dangerous common forms of radiation are. A dental X-ray, for example, gives you about as much radiation as 2.5 bananas, while flying across country exposes you to about 400 bananas’ worth of radiation.

The radiation in a banana is natural, and because your body contains the same atoms as the foods you eat, you are naturally radioactive as well. Of course, technology has increased the amount of radiation in food and people, and sometimes, that increased radiation can be traced to specific events. For example, scientists from the College of William & Mary as well as the University of Maryland have studied the radioactive content of honey in the United States. They have found that it is surprisingly rich in radioactive cesium, which is not natural. It is produced by nuclear weapons and the tests associated with them. Plants require potassium to live, but cesium and potassium have similar chemical properties (anyone who has taken my chemistry course should know why), so plants can take up and use cesium instead, including the radioactive cesium made by an atomic bomb.

The researchers found that while there were no atomic bombs exploded in or around the eastern United States, the honey found there has detectable amounts of radioactive cesium. More importantly, there is a definite pattern to how much is found. There is significantly more radiation found in honey made in the southeastern United States, particularly Florida. In fact, the honey found in Florida can be as much as 500 times more radioactive than the honey found farther north. Now that sounds scary, but in fact, even the most radioactive honey they analyzed had only 18% as much radiation as a banana. Thus, it poses no threat to people who eat it, but we don’t know if it affects the bees that make and eat it. However, it does tell scientists that the radioactive materials released in nuclear explosions are not dispersed evenly throughout the world. Instead, weather patterns tend to concentrate them in specific regions.

The other thing the researchers show is that the more potassium found naturally in the soil, the less radioactive cesium found in the honey. Thus, even in Florida, honey from regions where the soil had a high potassium content was less radioactive than honey from regions where the potassium content was lower. As a result, if you want less radiation in your honey, you need to make sure the flowers from which it is made are grown in soil that is rich in potassium.