Super fact 73 : The second law of thermodynamics, or the fact that entropy is always increasing in an isolated system does not contradict evolution. Life is not a closed system. The environment is providing energy, the sun is providing energy, geological forces are providing energy, etc.
A lot of people have never heard of the second law of thermodynamics, or entropy and are unaware of the claim that the second law of thermodynamics contradicts evolution. So how can debunking this claim be surprising, and a super fact? The reason is that this is a popular claim among creationists and according to this Gallup poll 40% of Americans believe in creationism. The fact that this popular but false claim is rooted in a very basic misunderstanding of the second law of thermodynamics and what entropy is makes it super fact.
In the past I’ve read many creationist books that make the claim that the second law of thermodynamics contradicts evolution. One of them was Scientific Creationism (1985) by Henry M. Morris (the father of modern creation science), where he stated that the second law of thermodynamics says that everything tends towards disorder, making evolutionary development (ordering) impossible. The Death of Evolution: Restoring Faith and Wonder in a World of Doubt by Jim Nelson Black, another book I read, and which I gave a one star review on Amazon, makes the same claim. I’ve also come across a lot of people making this claim.
The people who make the claim that the Second Law of Thermodynamics contradict evolution typically do not understand the second law of thermodynamics and do not know what entropy is. Despite that fact they see it as a powerful argument against evolution. I’ve even seen it used against highly respected physics professors who “believe in”, well accept the reality of evolution, by people who had no understanding of the second law of thermodynamics. At one point I even believed the claim myself. Then I studied physics, and well, oops, I was forced to admit that I had been bamboozled.
The Second Law of Thermodynamics
The Second Law of Thermodynamics states that the total entropy (disorder) of an isolated system always increases over time. This means that natural processes tend to move from order to disorder (within the isolated system). It should be noted that disorder is a popular but imperfect metaphor for entropy. Entropy is not the same thing as what people think of as disorder. In physics entropy refers to the logarithm of the number of microstates compatible with the system’s measurable macroscopic state. As molecules randomly arrange themselves into new macroscopic states, the number of possible microstates will increase.
It also means that heat will spontaneously flow from hotter to colder objects, but never the reverse. Another thing it means is that mechanical energy can be converted to thermal energy, but never the reverse. It turns out that those seemingly different statements are physically identical.
It is very possible that the entropy of an organism is lower compared to a blob corresponding to all its molecules randomly distributed within a blob. However, that organism did not evolve in isolation inside a hermetically enclosed box without any energy from the outside. Life and evolution operate in an environment full of energy coming from the sun, the Earth, winds, oceans, geological forces, radiation, etc. Evolution does not take place in an isolated system.
It is also important to understand that within an isolated system, pockets of lower entropy can form if they are offset by increased entropy elsewhere within the system. That’s what the word “total” in total entropy means. Crystal formation is an example of creating local pockets of lower entropy (less “disorder”) within a system, but this is always accompanied by a greater increase in entropy in the surroundings. The Universe is an isolated system so the entropy within the Universe should always increase, but again the local pockets of lower entropy that evolution may create are accompanied by a greater increase of entropy elsewhere.
Below is a YouTube video explaining how the second law of thermodynamics does not contradict evolution.
Entropy – Arrow of time
An interesting aspect of the second law of thermodynamics is that it makes entropy serve as an arrow of time. In general, the fundamental laws of physics are time reversible. The equations work the same forwards and backward in time. The equations for gravity, electromagnetism, and the strong nuclear force work the same regardless of time’s direction. An example is if you filmed a planet orbiting a star and played it backward, it would still follow the laws of motion the same way.
Throw a bunch of billiard balls on the floor and film them bouncing and hitting each other and the walls. If you then run the film backwards and forwards it would be far from obvious which is forward and which is backwards, except for the fact that the balls will slow down due to friction. However, balls slowing down due to friction is mechanical energy turning into heat, which is an example of the second law of thermodynamics. The fundamental laws of physics are time reversible, but the second law of thermodynamics is a notable exception. Entropy always increases in an isolated system (like the Universe). By measuring entropy, you can distinguish the past from the future, giving time a direction
Another evolution related post is: Evolution is a fact
Super Facts 