Really Generous Bacteria!

This is an electron microscope image of a bacterium from genus Prochlorococcus. The colors were added artificially. (click for credit)
This is an electron microscope image of a bacterium from genus Prochlorococcus.
The colors were added artificially. (click for credit)

The image you see above is of a tiny bacterium from genus Prochlorococcus. It is part of a phylum of bacteria called Cyanobacteria, and the members of this phylum are an incredibly important part of the world’s ecosystems. They live in water, converting sunlight and carbon dioxide into sugar and oxygen via photosynthesis. Estimates indicate that cyanobacteria are responsible for producing about 20 to 30 percent of the earth’s oxygen supply.

Prochlorococcus are particularly important cyanobacteria. They are thought to be the most abundant photosynthetic organism on earth, with an estimated worldwide population of an octillion (1,000,000,000,000,000,000,000,000,000).1 More importantly, they tend to live in parts of the ocean that are nutrient-poor. Their photosynthesis helps to alleviate this problem, of course, making them a food source for other organisms that might try to live there.

Dr. Sallie Chisholm at the Massachusetts Institute of Technology (MIT) first described the organisms in 1988 and has continued to study them over the years. She and her colleagues were recently looking at them under an electron microscope and noticed what she described as, “these pimples – we call them ‘blebs’ – on the surface.”2 Dr. Steven J. Biller, a microbiologist who is also at MIT, recognized the blebs as vesicles, which are tiny “sacs” made by nearly every cell in nature. Since the vesicles were found on the surface of the cell, the scientists decided the bacteria were using them to get rid of whatever was inside the vesicles.

They studied the water from their laboratory samples and found that it was, indeed, rich with vesicles that had been released by the Prochlorococcus, and they were surprised by what they found inside.

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It Did Sound Too Good to be True…

These are stem cells taken from the embryo of a mouse. The color is the result of a stain used to make them easier to see. The embryo had to be killed to get the cells, but they can develop into almost any kind of mouse cell (skin, nerve, muscle, etc.). (image in the public domain)
These are stem cells taken from the embryo of a mouse. The color is the result of a stain used to make them easier to see. The embryo had to be killed to get the cells, but they can develop into almost any kind of mouse cell (skin, nerve, muscle, etc.).
(image in the public domain)

Every once in a while, I run across a story in the scientific literature that seems just too good to be true. Such was the case when I was reading the February 22nd issue of Science News. In a story entitled “A little acid can make a cell stemlike,”1 the author reported on some amazing results that were published in the journal Nature. In the published studies, scientists from the RIKEN Center for Developmental Biology in Kobe, Japan claimed that they could take cells from various parts of a mouse (like the brain, skin, and liver) and transform them into stem cells by simply treating them with acid or other external stimuli!

This would be an amazing feat, because stem cells are able to develop into many different kinds of cells. Consider, for example, what happens when two mice successfully mate. The sperm from the male fertilizes the egg from the female, and the result is a single cell that will eventually develop into a new mouse. In order for that to happen, the cell begins making copies of itself. As more and more copies are made, the individual copies begin to start “specializing” so they can do specific tasks. Some develop into skin cells, others develop into nerve cells, others develop into blood cells, etc. This process of cells specializing into different types of cells is called differentiation.

Of course, the cells in the developing mouse don’t start differentiating right away. There has to be a group of cells that have the ability to produce all the different kinds of cells the mouse needs, and these cells are generally called embryonic stem cells. Examples of mouse embryonic stem cells are shown in the image above. They may look unassuming, but they are truly amazing, because they can produce any kind of cell that the mouse needs. Of course, in order to produce that image, the mouse embryo from which the cells came had to be destroyed. In other words, to get mouse embryonic stem cells, you have to kill the mouse whose cells you want. If you want human embryonic stem cells, you have to kill the developing baby whose cells you want.

This, of course, presents a problem. Embryonic stem cells have great potential when it comes to solving many medical issues. Suppose, for example, you have a heart attack. As a result, some of the cells that make up your heart muscle died. In most cases, the body can’t completely replace the cells that are killed, so you will probably have a weaker heart for the rest of your life. If stem cells could be used, perhaps they could differentiate into heart muscle cells and completely repair the damage to your heart.

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The More We Learn About Bone, The More Amazing It Is!

This is the latest view of the microscopic structure of bone. (click for credit)
This is the latest view of the microscopic structure of bone. (click for credit)

The bones that make up the skeletons of animals and people are a marvel of engineering. As one materials scientist put it:1

…bone properties are a list of apparent contradictions, strong but not brittle, rigid but flexible, light-weight but solid enough to support tissues, mechanically strong but porous, stable but capable of remodeling, etc.

More than three years ago, I posted an article about research that helps to explain why bones are so strong. The calcium mineral that makes up a significant fraction of the bone, hydroxyapatite, is arranged in crystals that are only about three billionths of a meter long. If the crystals were much longer than that, the strength of the resulting bone tissue would be significantly lower. What restricts the size of the crystals? According to the previous research, the tiny crystals are surrounded by molecules of citrate. It was thought that the citrate latches onto the outside of the crystal, stopping it from growing.

Some very interesting new research from the University of Cambridge and the University College London indicates that this is, indeed, what happens. However, it also indicates that citrate does much more than simply restrict the size of the crystals. It also helps to produce a cushion that allows bones to flex rather than break when they are under stress.

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The 2014 Southeast Homeschool Convention

This is me standing in front of my publisher's booth at the Southeast Homeschool Convention.
This is me standing in front of my publisher’s booth at the Southeast Homeschool Convention.

As I wrote in my previous post, last week was a very busy week. It started off in North Carolina, where I spoke at a church, a bookstore, and two classes made up of homeschooled students. I then traveled to Greenville, South Carolina to speak at the Southeast Homeschool Convention. This is part of the Great Homeschool Conventions, and I am scheduled to speak at all of them this year. I did the same thing last year, but this year was different, because I now have new books to sell.

Last year, I just sat in an empty booth and waited for people to come to talk with me. It got to be a bit dull at times, because without something in the booth, most people passed right on by. Of course, I had several great conversations with people who specifically sought me out to talk with me, but there was a lot of “down time” in between those conversations. This year, my new publisher (Berean Builders) had a booth, so when I wasn’t speaking, I hung out there. The publisher had my new elementary series, but it also sells the books I wrote with my previous publisher, so people could come to that one booth to see all the books I have written over the years.

The attendance at the convention was great (up significantly from last year), and I got to speak with a lot of people, both after my speaking sessions and at my publisher’s booth. I did three solo talks this year: Recent News in Creation Science discusses some of the more recent scientific studies that confirm the predictions of young-earth creationism or falsify the predictions of evolution. The Bible: A Great Source of Modern Science discusses some of the scientific facts that were written in Scripture long before science figured them out. Finally, Teaching Elementary Science Using History as a Guide discusses the rationale behind my new elementary science series.

I also did two talks with Diana Waring, who not only has an excellent history curriculum but is also about to re-release a series called Experience History Through Music. This three-CD/book set allows you to hear some of the classic songs written during different parts of U.S. history and learn the history behind them. It is a delightful product that allows students to not only learn history, but experience it! It would be an excellent supplement to any study of U.S. History. The talks we did this year were I Didn’t See That Coming and Arguing to Learn. The former was about what to do when your young-adult children make decisions that are unexpected, and the latter is about how debating different points of view can be an effective learning tool.

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Speaking in the Raleigh, North Carolina Area

This is me talking with some homeschool students at The Homeschool Gathering Place. I ended up signing the young man's cast, which was surprisingly difficult because of its texture.
This is me talking with some homeschool students at The Homeschool Gathering Place. I ended up signing the young man's cast, which was surprisingly difficult because of its texture.

Last week was really busy. That’s why I haven’t written a post since the 13th. It started with a trip to The Homeschool Gathering Place in Raleigh, North Carolina. That’s where the photo above was taken. The owners of the store, who have been a blessing to homeschoolers for the past 18 years, arranged for me to speak at a nearby church, Colonial Baptist. It was a huge church, and the homeschool group there is quite large, so the turnout was great.

At the church, I showed several videos that demonstrate mutualism, which is something I find incredibly fascinating (see here, here, here, and here for a few examples). I also showed videos about some of the amazing design you see in nature, such as the way octopodes (the best plural of octopus) camouflage themselves. I then spoke about the recent scientific studies that either confirm the predictions of creation science or falsify evolutionary predictions, most of which has been discussed on this site. Not surprisingly, the videos were the biggest hit.

After the event at the church, I went back to The Homeschool Gathering Place and gave a talk about teaching science using history as a guide. That’s how my new elementary science series is designed. The talk was much more intimate, by design, and it generated a lot of good discussion. I also got to talk with students while I was there, as the picture above shows.

In between these appearances, I got to spend some time with an old friend, who I call “Roxy.” I think I might be the only one who still calls her that. She and I grew up together, but she left Indiana, and the last time I had seen her was more than 10 years ago. We seem to have the beginnings of a mutual admiration society going. She kept telling me how proud she was of what I had accomplished over the years, and I kept telling her how impressed I was with her. She is a very talented dancer, and I always looked up to her as we were growing up. Today, she is a mother who has raised great young adults. She also teaches dance and history to groups of homeschooled students. I got to help her teach two of her classes (history, not dance!), and those young students are incredibly blessed to have her! She is changing lives, and I am proud to call her my friend.

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Fascinating: Your Brain Gets Heavier When You Think!

This is a drawing of Angelo Mosso's circulation balance from the 1880s.
This is a drawing of Angelo Mosso’s circulation balance from the 1880s.

In the 1880s, an Italian scientist named Angelo Mosso built a balance that tried to measure the net flow of blood in the body. A man was put on the balance and asked to clear his mind. The balance was then set so that it stayed horizontal. The man was then asked to read something, and invariably, the balance tilted towards the head, indicating that his brain got heavier. According to Mosso, when the man read a newspaper, the balance would tilt a bit, but when he read a page from a mathematics manual, the balance would tilt more. One man was asked to read a letter from an angry creditor, and it tipped the balance more than anything else!

These results led Mosso to conclude that when the brain is actively working, it gets more blood from the circulatory system. The more it has to work (to process difficult information or strong emotions), the more blood it gets. When I originally read about Mosso’s work years ago, it reminded me of Dr. Duncan MacDougall’s experiments in which he tried to weigh the soul. If you have never heard of Dr. MacDougall’s work, he tried to measure the weight of six terminally-ill patients at the moment they died. He then did the same procedure on dogs. He claimed that while the people lost weight when they died, the dogs did not. As a result, he claimed to have demonstrated that the human soul has weight.

Of course, there are all sorts of problems with Dr. MacDougall’s work, and when I read about Mosso’s work, I rashly put it in the same category. While I am more than willing to believe that the brain needs more nutrients when it is hard at work, I have a hard time believing that its blood flow patterns would be changed dramatically enough to be measured by a balance. Fortunately, other scientists weren’t so rash. Dr. David T. Field and Laura A. Inman decided to replicate Mosso’s experiments, and the results surprised me.

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This Climate Study Claims to Have the “Right Stuff”

This graph shows the predictions of the most popular global climate models (lines with no squares or circles) compared to global temperature measurements made by weather balloons (circles) and satellites (squares). [The graph is from the report being discussed.]
This graph shows the predictions of various IPCC global climate models (lines with no squares or circles) compared to global temperature measurements made by weather balloons (circles) and satellites (squares). [The graph is Figure 1.1 from the report being discussed.]

It is well known in the scientific literature that the computer models being used by the U.N.’s Intergovernmental Panel on Climate Change (IPCC) have done a miserable job in predicting the change that has occurred in global temperature over the past two decades. You can see that for yourself by looking at the graph shown above. The various lines that have no circles or squares on them are the results of the climate models used by the IPCC. Notice that no model comes close to lining up with the actual data (the squares and circles). Indeed, the later the date, the worse the models become when compared to the data.

A group of retired NASA scientists and engineers led by Dr. Harold H. Doiron, a mechanical engineer who is best known for his work on eliminating unstable vibrations in liquid propellant rockets, has decided that these models simply can’t be used to make rational decisions about earth’s future climate. As this group says:

We have concluded that the IPCC climate models are seriously flawed because they don’t agree very closely with measured empirical data. After a 35 year simulation the models over-predicted actual measured temperatures by factors of 200% to 750%. One could hardly expect them to predict with better accuracy 300 years into the future required for use in regulatory decisions.

So what are we to do? If we can’t properly model how the earth will respond to increased carbon dioxide concentrations, how can we estimate what the consequences will be if we do nothing to curb the activities that are filling earth’s atmosphere with excess carbon dioxide?

In this research team’s mind, the answer is to look at the actual data and develop an empirical estimate. After all, we have about 100 years of measured data when it comes to global temperature, and we have a few thousand years of data that can help us estimate how the earth’s temperature has changed over that timeframe. In addition, we have measurements and estimates for how the amount of carbon dioxide in earth’s atmosphere has changed over time. If we look at past correlations between carbon dioxide and temperature, perhaps they can tell us what future correlations will be.

I have to admit that I am surprised no one has used this approach before. Sure, climate scientists have studied the correlations between past global temperatures and past atmospheric carbon dioxide concentrations, but this is the first time of which I am aware that scientists (and engineers) have tried to use those correlations to make definitive predictions about the future.

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Salmon Seem to Inherit a Map for Their Migration

This is a Chinook salmon in its parr stage. (click for credit)
This is a Chinook salmon in its parr stage. (click for credit)

Pacific salmon are fascinating to study, because their lifecycle is so interesting. They hatch in freshwater streams, at which point they are called alevin. Although they have hatched, they still have a yolk sac upon which they feed. Once they have absorbed the yolk sac, they are called fry, and they begin feeding on the plankton in the stream. They eventually mature into parr, which are also called fingerlings. After about 12-18 months in freshwater, they move to the brackish waters of estuaries, ecosystems where freshwater rivers meet the ocean. At this point, they are usually called smolts. After a few months, they venture out into the ocean, where they will spend several years growing.

The amazing part, of course, is that after spending several years in the ocean, they return to the same freshwater stream where they hatched to spawn another generation. From a scientific point of view, one of the most important questions you can ask about this lifecyle is, “After spending years in the ocean, how do the salmon know the way back to the freshwater stream in which they hatched?” It makes sense that while they are fry and parr, they get a good sense of the mix of chemicals that make up their “home stream,” but they obviously can’t follow that trail of chemicals from the ocean! So how do they get from the ocean to the correct estuary so that they can get back to the stream in which they hatched?

About a year ago, I discussed a study that gave a partial answer to that question. It showed that sockeye salmon use the earth’s magnetic field as a “map” that leads them to the proper estuary. The study suggested the salmon had other means of navigation at their disposal, but the magnetic field was a very important tool in the fish’s repertoire. How do the salmon acquire this map? In the previous study, it was suggested that the map is imprinted in the salmon’s brain as it is traveling from the estuary to the open ocean.

Well, the same research team has done a follow-up study, and they have decided that this suggestion is probably not correct. Instead, the real story is more complex and much more interesting!

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More Evidence That Antibiotic Resistance Existed LONG BEFORE Antibiotics Were Developed

This is a drawing of a bacteriophage, a virus that attacks bacteria. (click for credit)
This is a drawing of a bacteriophage, a virus that attacks bacteria. (click for credit)
Many people know that bacteria have developed resistance to popular antibiotics. Indeed, it is a big problem in medicine, and it has caused many health-care providers to call for doctors to prescribe antibiotics only when they are necessary. The Centers for Disease Control calls this “antibiotic stewardship” and thinks it will improve medical care throughout the country.1 I have written about antibiotic resistance before (see here and here), because some evolutionists try to cite it in support of the idea that novel, useful genes can be produced by evolutionary processes. Of course, the more we have studied the phenomenon, the more we have seen that this is just not the case.

There are essentially two ways that a bacterium develops resistance to an antibiotic. One way is to have a mutation that confers the resistance. For example, a bacterium can become resistant to streptomycin if a mutation causes a defect in the bacterium’s protein-making factory, which is called the ribosome. That defect keeps streptomycin from binding to the ribosome, which makes streptomycin ineffective against the bacterium. However, it also makes the ribosome significantly less efficient at its job.2 So in the end, rather than producing something novel (like a new gene that fights the antibiotic), the mutation just deteriorates a gene that already existed. While this is good for a bacterium in streptomycin, it doesn’t provide any evidence that novel, useful genes can be produced by evolutionary processes.

There is, however, a second way that a bacterium can develop resistance to an antibiotic: It can get genes that fight the antibiotic from another bacterium. Bacteria hold many genes on tiny, circular portions of their DNA called plasmids. Two bacteria can come together in a process called conjugation and exchange those plasmids, which allows bacteria to “swap” DNA. If a bacterium has a gene (or a set of genes) that allows it to resist an antibiotic, it can pass those genes to others in the population, ensuring their survival.

Of course, the natural question one must ask is, “Where did those antibiotic-resistance genes come from in the first place?” Many evolutionists want you to believe that evolution produced those genes in response to the development of antibiotics. After all, antibiotics didn’t exist until 1941, when penicillin was tested in animals and then people. Why would antibiotic-resistance genes exist before the antibiotics?

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Bacteria Put Out “Welcome Mats” for Tubeworms

On the left, you see a tubeworm with its feathery feeding appendages extended. On the right, the tubeworm has retracted those appendages, and you see only the opening of its tube.
On the left, you see a tubeworm with its feathery feeding appendages extended. On the right, the tubeworm has retracted those appendages, and you see only the opening of its tube.

When I scuba dive, I love finding tubeworms like the one pictured above. As adults, these worms build tubes made out of calcium carbonate to house their delicate bodies. They feed by extending feathery appendages called radioles, which catch nutrients that are floating in the water. On the left side of the picture above, you see a tubeworm with its radioles extended. However, if you scare a tubeworm (I do so by flicking my fingers at it), the worm will pull its radioles back into its tube for protection. At that point, you see only the opening of the tube, which is shown on the right side of the picture above.

An adult tubeworm spends its life attached to a hard surface, such as a piece of coral, a rock, or even the hull of a ship. However, when a tubeworm egg hatches, the larva that emerges is free-swiming and looks nothing like the adult. In order to mature, it must find a surface to which it can attach itself. It has long been known that tubeworm larvae tend to attach themselves to surfaces that contain specific bacteria, but no one understood how the larvae know where the bacteria are.

Nicholas J. Shikuma and his colleagues have done a study that helps us understand this amazing process. They concentrated on a specific species of tubeworm, Hydroides elegans, which is a common nuisance because it tends to stick to the hulls of ships (that’s not the species pictured above). They already knew that these tubeworms tend to settle where a specific bacterium, Pseudoalteromonas luteoviolacea, is found. As a result, they studied the bacterium in detail, and they found something rather incredible.

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