In short, no; evolution does not contradict any law of thermodynamics, nor does it contradict the law of cause and effect, another common objection to evolution by the scientifically challenged. I will discuss each of these in detail and show how these objections arise from a misunderstanding of both evolutionary theory and thermodynamics.
The First Law of Thermodynamics can be stated as: "Energy can be changed from one form to another, but it cannot be created or destroyed. The total amount of energy and matter in the Universe remains constant, merely changing from one form to another." Living cells use energy from the sun (electromagnetic energy) or chemical potential energy to grow and repair themselves. They change the form of energy but do not create or destroy it. There is no violation of the first law.
The Second Law of Thermodynamics can be stated as: "In all energy exchanges, if no energy enters or leaves the system, the potential energy of the state will always be less than that of the initial state." What those who think that the second law is violated omit is that the second law refers to closed systems, those which have no exchange of energy with their surroundings. They thus ignore the fact that there is a constant stream of energy from the Sun that is captured by living organisms at the base of the food chain. It is this energy input that allows an organism to increase its order. Living organisms achieve order by using energy to grow and repair themselves. In the process, they create energy in the form of heat that is ultimately radiated, conducted, or convected away. This heat (electromagnetic energy in the infrared, i.e., IR radiation, and molecular motion) represents the entropy that is created as either electromagnetic energy from the Sun (photons) or chemical energy, such as some bacteria who use sulfur and iron compounds as a source of energy, is converted to another form of energy in the process of living.
The Law of Cause and Effect: "Nothing happens by chance." is the simplest way of stating it. Firstly, it is violated by quantum mechanics. "Spooky action at a distance" has been demonstrated experimentally. The random nature of radioactivity has been demonstrated experimentally. Those are just a couple of examples where the classical concept of causality fails. Secondly, it is violated by the replication process of RNA and DNA when living organisms reproduce.
Here are two features of evolutionary theory that are random: copying errors when cells divide and acquiring the complete genome of another organism. Both of these are amply documented in the scientific literature. What is not random is natural selection. If the change in the organism that results from a random change of its genome does not give it an advantage in the number of offspring with the same genomic change, then it will not survive as a new variant of the original species. If it does provide an edge, then the change will spread through the population that shares the same environmental conditions. If conditions change, a different variant may be favored. If enough genetic changes accumulate, it may become a new species. In the case of acquiring a new genome, such as in the case of an advanced set of symbionts like some lichens, it will become a new species. But its survival and spread depends on how it adapts to its environment in comparison to other variants of the parent species. This also is amply documented in the scientific literature. Evolution clearly does follow causality at the organism level, although the changes to the genome may be random.
The Second Law of Thermodynamics can be stated as: "In all energy exchanges, if no energy enters or leaves the system, the potential energy of the state will always be less than that of the initial state." What those who think that the second law is violated omit is that the second law refers to closed systems, those which have no exchange of energy with their surroundings. They thus ignore the fact that there is a constant stream of energy from the Sun that is captured by living organisms at the base of the food chain. It is this energy input that allows an organism to increase its order. Living organisms achieve order by using energy to grow and repair themselves. In the process, they create energy in the form of heat that is ultimately radiated, conducted, or convected away. This heat (electromagnetic energy in the infrared, i.e., IR radiation, and molecular motion) represents the entropy that is created as either electromagnetic energy from the Sun (photons) or chemical energy, such as some bacteria who use sulfur and iron compounds as a source of energy, is converted to another form of energy in the process of living.
Here are two features of evolutionary theory that are random: copying errors when cells divide and acquiring the complete genome of another organism. Both of these are amply documented in the scientific literature. What is not random is natural selection. If the change in the organism that results from a random change of its genome does not give it an advantage in the number of offspring with the same genomic change, then it will not survive as a new variant of the original species. If it does provide an edge, then the change will spread through the population that shares the same environmental conditions. If conditions change, a different variant may be favored. If enough genetic changes accumulate, it may become a new species. In the case of acquiring a new genome, such as in the case of an advanced set of symbionts like some lichens, it will become a new species. But its survival and spread depends on how it adapts to its environment in comparison to other variants of the parent species. This also is amply documented in the scientific literature. Evolution clearly does follow causality at the organism level, although the changes to the genome may be random.
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