Dr. Hunter had a post on his blog a few days ago dealing with evolution and whether or not it could be falsified. As he states, falsification is an incredibly important part of science. Indeed, the great philosopher Sir Karl Popper pointed out that science cannot prove anything. Instead, the best science can do is pile up evidence to support a theory. The more evidence that supports the theory (and the less evidence that opposes the theory), the more reasonable it is to believe the theory. However, the theory can never be proven.
In Popper’s view (and I agree with him), while you can never prove a scientific theory, you should be able to demonstrate it to be incorrect. In other words, a scientific theory should be falsifiable. There should be the possibility that some discovery would end up demonstrating that the theory is false. If a scientific theory can accommodate any data, it is not a scientific theory. This, of course, makes sense. If a theory is so plastic that it can be molded to fit any data, it is definitely not scientific.
Dr. Hunter says that evolution is not falsifiable because it is a negative argument. As he puts in in the post mentioned above:
Evolution is, and always has been, motivated by failures of creationism and design. If god did not design or create this world, then it must have evolved. Somehow. Evolutionists perform research to try to figure out how evolution could have happened, but it must have happened—that much they know. That is a metaphysical position, not a scientific position, based on a negative argument. It is not falsifiable.
While I agree with the last sentence in that quote, I don’t agree with anything that comes before it.
Bioluminescence is an amazing thing. Many living creatures use it to “light up” so they can communicate with others, more easily find food, or defend themselves against predators. In the picture above, for example, there are millions of single-celled organisms (called “dinoflagellates”) in the water. When they are disturbed, they use bioluminescence to glow. They are glowing in the picture because the wave is disturbing them. This is actually a defense mechanism. If the water is disturbed by an animal that eats them (such as a manta ray), the dinoflagellates glow, and the light might attract a predator that will eat (or scare away) the manta ray.
E. A. Widder wrote a review1 of bioluminescence in the May 7th issue of the Journal Science, and it is fascinating. As Widder points out, there are over 700 genera (the classification level above species) of organisms that use bioluminescence, and most of them (about 80%) live in the ocean. The mechanisms by which this process works are elegant and amazing, and they certainly defy any coherent evolutionary explanation.
It seems simple enough. The sun warms our planet. Thus, if one is wondering what is happening to the temperature of our planet, one should look for changes that are occurring in the sun. Sure, there are a lot of other things one must investigate as well, but the sun should be a major priority, right?
Well, not according to the Intergovernmental Panel On Climate Change (IPCC). In their 2007 report,1 which claims that “Warming of the climate system is unequivocal” and that there is a “very high confidence that the net effect of human activities since 1750 has been one of warming,” they state:
Solar irradiance contributions to global average radiative forcing are considerably smaller than the contribution of increases in greenhouse gases over the industrial period.
So the IPCC says that the huge ball of thermonuclear reactions upon which the earth depends isn’t nearly as important when it comes to climate change as the relatively recent 35% increase in atmospheric carbon dioxide.
Fortunately, not everyone thinks the IPCC is serious about science. As a result, some climate researchers are actually trying to figure out how important changes in the sun’s activity are when it comes to the overall temperature of the earth. Not surprisingly, current research is showing that the conclusions of the IPCC are wrong.
Before the human genome was sequenced, it was thought that humans had well over 100,000 genes. This reasonable conclusion was based on the fact that that the human body is estimated to produce 120,000 – 140,000 different proteins. Since biology had determined that a gene tells a cell how to make a protein, it was assumed that 120,000 – 140,000 proteins would require 120,000 – 140,000 different genes.
As is often the case with science, however, the data turned out to be very surprising. When the human genome was initially sequenced, it was estimated to contain about 30,000 genes. Today, it is thought that the human genome contains 20,000–25,000 genes.1
So if a human cell requires a gene in order to make a protein, and if the human body produces as many as 140,000 different proteins, how can it do so with “only” 20,000–25,000 genes? A large part of the answer to that question has to do with an amazing process called alternative splicing.
In my previous post, I discussed the proper way to apply the Second Law of Thermodynamics to a simple process: the freezing of water in a bucket. Now I want to apply the Second Law of Thermodynamics to the process of evolution. This is a difficult thing to do, because currently, there is no accepted mechanism for the process of evolution. Evolution might occur according to the Neo-Darwinian Synthesis; it might occur via punctuated equilibrium; it might occur according to the evo-devo view; it might occur as a result of facilitated variation; it might occur by some as yet undiscovered mechanism; or it might occur as a result of a combination of all or some of these mechanisms.
Even though there is no agreed-upon mechanism for evolution, some general statements can be made about the supposed process, and that should be enough to allow us to roughly apply the Second Law of Thermodynamics to it. In general, evolution says that organisms increase in complexity over time. A single-celled organism, for example, eventually developed the ability (through some as yet unknown process) to cooperate with other cells, which eventually led to a multicelled organism. Clearly, a multicelled organism is more complex than a single-celled organism, so via that unknown process, “simpler” single-celled organisms gave rise to “more complex” multicelled organisms. These multicelled organisms began to develop (once again, through some as yet unknown process) more “advanced” features, so that eventually a large diversity of life formed.
The longer evolution had to work through its unknown process, the more complex living creatures became. Thus, while it took some time for the evolutionary process to create relatively “simple” multicelled creatures, it took more time for evolution to produce complex invertebrates, and it took more time for evolution to produce vertebrates. The more “advanced” the vertebrate, the longer it took for evolution to produce it.
I was reading Dr. Hunter’s blog yesterday, and he had a post about entropy and evolution. In that post, he cited an article that comes to the right conclusion on the issue, but for the wrong reason. In fact, I am surprised that it passed peer review, since it promotes a very bad misconception regarding the Second Law of Thermodynamics. Because both creationists and evolutionists do a very poor job of applying the Second Law of Thermodynamics to the concept of origins, I thought I would try to explain the proper way to interpret the Second Law of Thermodynamics. In the next post, I will then apply the Second Law to the concept of evolution.
Before I get started, however, let me tell you the overall conclusion. The Second Law of Thermodynamics DOES NOT forbid the process of evolution. I know there are many creationists out there who claim that it does, but they are simply wrong. In addition, I know there are a lot of evolutionists out there who claim that it doesn’t, but they do so for reasons that are often wrong. So let’s talk about the Second law of Thermodynamics and how to properly apply it to many situations, including the process of evolution.
A recent issue of Science has a very interesting article on blood platelets.1 As nearly any textbook that discusses human anatomy and physiology will tell you, there are three main types of blood cells: red blood cells, white blood cells, and platelets. As indicated by the scanning electron microscope image above, platelets are the smallest of the three.
In addition, almost any textbook that discusses human anatomy and physiology will tell you that each blood cell is principally involved in one area of your body’s maintenance. Red blood cells are responsible for carrying oxygen to the tissues, although to a certain extent, they also pick up carbon dioxide waste from the tissues. White blood cells are responsible for cleaning the tissues of debris and fighting off invaders. Blood platelets are involved in clotting the blood so that we don’t bleed to death from a small cut.
Interestingly enough, this article indicates that blood platelets do a lot more than what most textbooks tell you!
In a recent issue of Science, there are a couple of short articles (called “Technical Comments”) about Ardipithecus ramidus. If you don’t remember this fossil, nicknamed “Ardi,” it was originally discussed in an October 2009 issue of the same journal.1 It was a collection of severely-crushed and poorly-fossilized remains that took more than 15 years to analyze. This analysis included a digital reconstruction of large portions of the skeleton. The skull pictured here, for example, is a digital reconstruction based on the crushed bones that were found.
At the time, Ardi was hailed as an amazingly important discovery, because the authors of the study claimed that the fossil’s features clearly showed it was a part of the supposed evolutionary lineage between an apelike ancestor and modern man. Indeed, Science called it the “breakthrough of the year” and said:
Even the earliest members of her species, Australopithecus afarensis, lived millions of years after the last common ancestor we shared with chimpanzees. The first act of the human story was still missing. Now comes Ardi, a 4.4-million-year-old female who shines bright new light on an obscure time in our past.2
The short articles I mentioned above disagree with some of the conclusions of the original studies on Ardi.
Craig Venter and his team have built the genome of a bacterium from scratch and incorporated it into a cell to make what they call the world’s first synthetic life form.
It’s an amazing feat of biotechnology, and the process he and his team produced might result in some incredible applications down the road. What I find interesting about the process, however, is how well it illustrates that life simply cannot come about as the result of random chemical reactions guided by some sort of selection process. In other words, this stunning achievement really demonstrates the impossibility of abiogenesis.
The scientific report of Venter and his team’s accomplishment can be found on the website of the journal Science1. I finally got around to reading it, and it is truly fascinating. When you look at the details of how they created their “synthetic” life form, you find that Venter and his team relied on already-living systems not once, not twice, but a total of three times. Without relying on these already-living systems, they would not have been able to produce their “synthetic” cell.