These Bifidobacterium longum bacteria are often found in the intestines of infants. (Click for credit)The breast milk that a mother feeds her baby is laden with bacteria. Does that sound bad? It shouldn’t! While there are some pathogenic bacteria, most bacteria are incredibly beneficial to the life that exists on this planet. That’s especially true of bacteria that live in and on people. It turns out that most people live in a relationship with more than 150 different species of bacteria, and the individual bacteria that participate in this relationship far outnumber the human cells that make up a person’s body. In one sense, then, a person is not an individual. Instead, he or she is a walking ecosystem!
Scientists now call the collection of bacteria that lives in a person’s body the microbiome, and as the article linked above indicates, each person seems to have his or her own special mix of bacteria in that microbiome. Indeed, some researchers think that analyzing the DNA of the bacteria a criminal leaves behind can aid in identifying that criminal in cases where his or her own DNA is not available at the crime scene or too degraded to analyze properly.1
So where does an infant start collecting the bacteria that will make up his or her own microbiome? One of the sources is the breast milk that the infant drinks. It has been known for quite some time that breast milk contains bacteria, but the details have not been well studied. However, a group of Spanish researchers have begun to shed some light on those details. They studied the breast milk of 18 mothers who varied in weight, weight gain during pregnancy, and the mode in which the baby was delivered. They sampled the milk these mothers produced at three different times: the first secretions of milk produced after giving birth (called colostrum), the milk that was produced one month after giving birth, and the milk that was produced six months after giving birth. They sequenced the DNA of the bacteria found in these samples of milk, and they came up with some amazing results.2
A commenter tried to claim that the Ediacaran fossil assemblages offer an explanation around the Cambrian Explosion, but had he actually read the link that was provided, he would have known that they do not. Instead, the Ediacaran fossils cannot be connected in any reasonable way to the fossils found in the Cambrian. To emphasize this, I quoted from N.S. Sharma’s book, Continuity and Evolution of Animals:1
Although the stratigraphic distribution of Ediacaran fossils is clear enough, their biological interpretation remains controversial, providing what amounts to a Rorschach test. Several distinct body plans are represented. Most radially symmetric fossils plausibly represent polypoid organisms or the inflated holdfasts of colonial, dipoblastic animals–mostly unrepresented in the modern fauna. More complex fossils include a range of forms built of repeated, tube-like units. In a stimulating, if controversial proposal, Seilacher grouped such fossils into a clade that he christened the Vendobionta and viewed as an extinct experiment in multicellular organization. Others have questioned that interpretation, assigning various forms to colonial diploblasts or to stem members of several bilaterian clades. It is genuinely difficult to map characters of Ediacaran fossils into the body plans of living invertebrates. Long viewed as the principal problem of interpreting Ediacaran assemblages, this difficulty increasingly appears to be their central point. (emphasis mine)
A paper that was recently published online by the journal Nature demonstrates that Sharma’s characterization of these fossils is right on the money.
A picture of a mineral formation that was widely interpreted as an animal fossil (Click for credit)The Cambrian Explosion presents a serious headache for evolutionists. After all, the fossils found in Cambrian rock are supposed to be about 540 to 485 million years old. However, when you look at the complex animals preserved in such rock, you find every major body plan that exists in today’s animals. Worse yet, when you look in layers that are supposed to be older than Cambrian rock, you don’t find the supposed ancestors of these complex animals. Evolutionists have desperately tried to explain around the problem, but so far none of their explanations work.
In 2004, a ray of hope appeared. The journal Science published an article claiming to have found animal fossils that are 40-55 million years older than the Cambrian fossils. They also seemed simpler than the animal fossils found in Cambrian rock. These simple animals were called Vernanimalcula guizhouena, and the authors thought that they helped to mitigate the evolutionary headaches caused by the Cambrian Explosion. As the authors state in their paper:1
The morphology of Vernanimalcula demonstrates that the evolutionary appearance of developmental programs required to generate a multilayered bilaterian body plan preceded the entrainment of the growth programs required for macroscopic body size. Furthermore, the organization of these fossils, taken together with their provenance, indicates that the genetic tool kit and patter formation mechanisms required for bilaterian development had already evolved by Doushantuo times, long before the Cambrian. Therefore, the diversification of body plans in the Early Cambrian followed from the varied deployment of these mechanisms once conditions permitted, not from their sudden appearance at or just before the Cambrian boundary.
So these fossils showed that the Cambrian Explosion wasn’t an explosion at all. Instead, simpler versions of the complex animals that appear in Cambrian rock existed previously, and the Cambrian era simply represented a rapid diversification of a basic body plan that had already existed in a simpler form.
Of course, like many evolutionary propositions, once this claim was thoroughly analyzed, it was shown to be utterly false.
More than three years ago, I wrote about the young, faint sun paradox. The problem is fairly simple: Based on everything we know about the thermonuclear reactions that power the sun, it is getting more luminous over time. In other words, the sun is producing more light now (on average) than it did in the past. As a result, the farther you go back in time, the dimmer it should have been. This presents a problem, because the dimmer the sun is, the cooler all the planets (including the earth) are. According to what we know right now, the earth would have been too cold to support life 3.6 billion years ago. Modern paleontology assures us, however, that there was life on earth at roughly that same time.
How do those who believe both modern paleontology and our current understanding of the sun resolve this problem? Unfortunately, the all-too-often response is to deny that there is a problem at all. For example, one old-earth website claims that this used to be a problem, but it has since been solved. It cites a 2010 study1 that merely suggested a possible issue that might reduce the problem. Based on that single study, the website proclaims:
The solving of this paradox provides us with a clear answer that is easily understood, and should eliminate this paradox from being used as evidence of a young earth. Once again, science has prevailed over the claims of young earth creationism.
Of course, nothing could be further from the truth. Indeed, in just over one year, the very same journal published a paper that categorically showed that the solution proposed by the 2010 paper was insufficient. Even giving the proposed solution the widest possible latitude, it fell short of resolving the paradox by a factor of two!2
In fact, this problem is still so difficult to resolve in the old-earth view that the Space Telescope Science Institute hosted a two-day symposium in hopes of starting to find a solution to it.
The "brains" of this surgical device is an iPod (Click for credit.)
Last month, I wrote an article about an experiment involving spiders and an iPod touch. The results of the experiment were interesting, but I also thought it was really cool that an iPod was integral to the experiment’s design. Well, I just learned about something that I think is is even cooler. It turns out that an iPod touch is being used to assist in knee-replacement surgeries!
The system is called “Dash,” and it is made by a company called Brainlab. It consists of several accessories, such as probes, that attach to an iPod touch. Once everything is sterilized, the surgeon can use the probes to make measurements on the patient while the surgery is in progress. The iPod can then do some calculations on those measurements and show an image that will help the doctor install the artificial knee as accurately as possible. It can also use its WiFi capabilities to send those results to any other device, such as an iPad, if the surgeon wants a larger, more detailed image.
Why would a surgeon use a device like this? Well, in order for the replacement knee to function well, it must be aligned properly. In conventional knee replacement surgeries, the surgeon inserts a metal rod into the femur (the bone above the knee) to help with this alignment. Unfortunately, that process can increase the risk of certain side effects, such as fat embolisms. When using this iPod-based device, there is no need for an alignment rod. In addition, a surgeon who has been using it for more than a year says that the device provides better alignment than the conventional method. This leads to a larger range of motion for the artificial joint. Also, patients experience less pain and swelling after surgery.
This tiny, transparent roundworm has amazing neurons. (Click for credit)In my high school textbook, I try to emphasize the fact that there is no such thing as a “simple” life form. Even the most basic living organism is a marvel of amazing complexity. Consider, for example, the tiny roundworm, Caenorhabditis elegans, pictured on the left. It is only 1 millimeter long, and because it is transparent, it is very easy to study. In addition, because it’s nervous system is considered “simple,” it has been examined extensively in order to understand how animal nervous systems work.
Why is its nervous system considered “simple?” Well, the functional unit of an animal’s nervous system is the neuron, a sketch of which is given below:
A simplified sketch of a neuron (Image in the public domain)
These individual cells receive signals in their dendrites and transmit them through the cell body and down the axon. Most animal nervous systems are made up of many, many neurons. For example, in the part of the brain known as the cerebral cortex, cats have about 300 million neurons, dogs have about 160 million neurons, and chimpanzees have about 6.2 billion neurons. The animal with the largest number of neurons in the cerebral cortex is probably the African elephant, topping off at about 11 billion neurons, but the false killer whale comes in as a close second, at about 10.5 billion. By comparison, the cerebral cortex of a person contains about 11.5 billion neurons.1
The entire nervous system of C. elegans is a mere 302 neurons. That’s really simple compared to people and animals isn’t it? Well…not exactly.
An artist's rendering of the Mars rover "Curiosity." (NASA image)
A friend of mine told me about a news story he heard on NPR. He said that NASA had some “really exciting” results from the Mars rover named Curiosity, but they were not ready to release the results to the public yet because they wanted to confirm the data. My friend wondered if perhaps NASA had finally found the remains of life on Mars. I found the story on NPR’s website, and it sounds like my friend’s expectation could be right.
According to the story, the principle investigator, Dr. John Grotzinger, says:
This data is gonna be one for the history books. It’s looking really good.
Dr. Grotzinger is waiting to release the results, however, because NASA has been burned a couple of times before. Back in 1996, NASA scientists published a paper that claimed a meteorite from Mars (named ALH84001) held tell-tale signs of bacteria, indicating that there was once life on Mars. As more scientists studied the meteorite, however, several problems with that interpretation were found. As a result, even though some NASA scientists are still saying that the meteorite holds evidence of life on Mars, the data are inconclusive at best.
In addition, NASA scientists published a paper in 2010 claiming to have found a bacterium that could incorporate arsenic into its biochemistry. NASA said that this finding would change the way we think about bacteria and would help us better understand the possibilities for life on other worlds. However, in just a couple of years, two very detailed studies showed that the original NASA claim was incorrect. It’s understandable, then, that NASA scientists are being careful when it comes to the release of any surprising data from the Curiosity rover.
On November 14, there was a solar eclipse that was visible from Australia, New Caledonia, New Zealand, South America, and Antarctica. I would have loved to use it as excuse to visit any of those places, but unfortunately, I couldn’t. However, I was pleased to receive the next best thing. A wonderful home educator who is field-testing my new elementary science curriculum with her family, Marianne Trinham, sent me pictures of the eclipse as seen from Brisbane. I hope you enjoy them!
While the eclipse was total in northern Australia, it was not total in Brisbane. Here is an image of the maximum of the eclipse as seen there:
How did this family get that image? They used binoculars to project it onto a white sheet of paper:
This species of catus worm, Priapulus caudatus, falsified another evolutionary prediction (click for credit)Look at the unassuming worm pictured on the left. It is commonly called a cactus worm, but this particular species is known as Priapulus caudatus. According to evolutionists, cactus worms have been around for at least 500 million years.1, but they just recently falsified yet another prediction made by the hypothesis of evolution. To understand the prediction and why it has failed, you need to learn some background information.
There are many different ways scientists classify animals, but one of the broader ways it is done is by symmetry. Most of the animals with which you are familiar are bilaterally symmetric. This means their bodies can be split into a left half and a right half, and those two halves are roughly mirror images of each other. Cats, dogs, and horses are all bilaterally symmetric, as they all have distinct right and left sides that roughly mirror each other. In addition, cactus worms are bilaterally symmetric. Since there are a lot of animals that have this kind of symmetry, scientists have to find characteristics among the bilaterally symmetric animals that will further classify them.
Well, there are two different ways that bilaterally symmetric animals develop their digestive tract. In all these animals, a puckered indentation forms in the embryo. This indentation, called the blastopore, forms the beginning of a tube that will eventually develop into the digestive tract. However, in some bilaterally symmetric animals, that blastopore ends up becoming the mouth, while in other bilaterally symmetric animals, the blastopore ends up becoming the anus. In other words, some animals start their digestive system with their mouth, while others start their digestive system with their anus. The “mouth first” animals are called protostomes, which is a combination of the Greek word “protos” (which means first) and “stoma” (which means mouth). The “anus first” animals are called deuterostomes, which means “mouth second,” since the Greek word “deuteros” means “second.”
So when a biologist looks at an animal that is bilaterally symmetric, one of the first questions that comes to mind is, “How does the digestive tract develop?” That tells the biologist whether the animal is a protostome or a deuterostome. Well, it turns out that studying the embryonic development of animals is rather time-consuming, so scientists often use other characteristics to infer the group to which an animal belongs. With all that under your belt, you are now ready to learn about the falsified evolutionary prediction.
The La Brea Tar Pits as imagined by Charles R. Knight (public domain image)
Paleontologists have long recognized that the fossil record produces a serious problem for the hypothesis of evolution. Almost thirty years ago, Dr. David Wake and his colleagues stated:1
With natural selection operating in a changing environment as an agent of adaptation, we expect to see changes at the organismal, ultimately physiological and morphological, level. How, though, can we explain the paradoxical situation in which environments change, even dramatically, but organisms do not?
In other words, evolution predicts that in a changing environment, organisms should change in order to adapt. However, when we look at the fossil record, we don’t see such change. Instead, while it is thought that earth’s climate changed dramatically in many different ways throughout the fossil record, the fossils themselves show that the organisms living on earth didn’t change much at all. This has been called the “paradox of stasis,” and while several attempts have been made to resolve the problem2, none of them have been found to be satisfactory.3
In an attempt to understand the paradox of stasis better, Dr. Donald Prothero undertook a series of amazingly detailed studies. With the help of a small army of students, Prothero studied the fossils of all the common birds and mammals that have been preserved in the La Brea tar pits of Los Angeles, California. According to the standard geological view, these tar pits preserved species that lived in the area over a period of time when the region experienced wild climate change. It is thought that 35,000 years ago, the Los Angeles, California area had a very similar climate to what it has today. During the height of the last ice age (20,000 years ago), however, it was significantly colder and significantly wetter. As the ice age waned, the climate returned to what it was 35,000 years ago.
From an evolutionary point of view, one would expect that over the course of this dramatic change in climate, the birds and mammals living in the area would have experienced some amount of evolutionary change in order to adapt to their surroundings. However, that’s not what this series of studies found.
