The Thermodynamics of Life
The second law is especially applicable when we investigate living organisms. Here we will see how living organisms maintain themselves in a state of low entropy to stay alive.
We have already discovered the dividing line between the simple and the complex, at the outer limit of what random action can do. We now know why complex structures cannot arise when natural selection is constrained to small changes. Our investigation used thermodynamics, as transformed into information theory, to conclude that Darwinism is inadequate to explain the presence of the rich variety of biological structures on Earth. This finding is negative, that is, it doesn’t say positively how we should modify Darwinism to produce an adequate explanation. In the second part of this chapter we will discuss the role of negative findings in advancing science.
We have already discovered the dividing line between the simple and the complex, at the outer limit of what random action can do. We now know why complex structures cannot arise when natural selection is constrained to small changes. Our investigation used thermodynamics, as transformed into information theory, to conclude that Darwinism is inadequate to explain the presence of the rich variety of biological structures on Earth. This finding is negative, that is, it doesn’t say positively how we should modify Darwinism to produce an adequate explanation. In the second part of this chapter we will discuss the role of negative findings in advancing science.
Living Organisms and Heat Engines
Sunlight is relatively low-entropy energy in comparison with heat. Light photons have a hundred times the energy of heat photons. Heat is therefore high-entropy energy. Ultraviolet rays have still lower entropy than the light from the Sun, but those that have the lowest entropy usually have a destructive effect. Most organic substances break down under exposure to the high-energy photons that travel in the ultraviolet rays of lowest entropy. When substances break down, they increase the Earth’s entropy. It takes chlorophyll to convert low-entropy energy into low-entropy food. We eat this food to keep ourselves in a state of low entropy.
Chlorophyll is a kind of heat engine that separates carbon and hydrogen from oxygen while expelling high-entropy heat at a low temperature. The carbon and hydrogen end up in the vegetable matter of the plant and the oxygen goes into the atmosphere. The separation of carbon and hydrogen from oxygen lowers the entropy of the atmosphere and permits animal life with organized movement and nervous systems like our brains. A source of low-entropy energy therefore sustains our ability to process information with intelligence.
Animals and humans are heat engines that use oxygen and release carbon dioxide. Plants use carbon dioxide and release oxygen. Plants and animals are complementary, but the plants had to come first. Oxygen is very reactive and is therefore usually found in combination with water, carbon dioxide, and minerals. The creation narrative is right when it says that vegetation came before animals and people. The plants conditioned Earth’s atmosphere for a long time before it was suitable for animals and people. How did Moses know that vegetation came before animals and people?
Chlorophyll is a kind of heat engine that separates carbon and hydrogen from oxygen while expelling high-entropy heat at a low temperature. The carbon and hydrogen end up in the vegetable matter of the plant and the oxygen goes into the atmosphere. The separation of carbon and hydrogen from oxygen lowers the entropy of the atmosphere and permits animal life with organized movement and nervous systems like our brains. A source of low-entropy energy therefore sustains our ability to process information with intelligence.
Animals and humans are heat engines that use oxygen and release carbon dioxide. Plants use carbon dioxide and release oxygen. Plants and animals are complementary, but the plants had to come first. Oxygen is very reactive and is therefore usually found in combination with water, carbon dioxide, and minerals. The creation narrative is right when it says that vegetation came before animals and people. The plants conditioned Earth’s atmosphere for a long time before it was suitable for animals and people. How did Moses know that vegetation came before animals and people?
Life without Sunlight
On Earth there are deep-sea hydrothermal vents where sunlight never penetrates but certain bacteria manufacture food from minerals. To do this they use the oxygen dissolved in the water. But how does oxygen get into the water? It comes from photosynthesis just under the surface of the sea. Chlorophyll in floating seaweed and plankton releases oxygen, but most of the oxygen dissolves in the water rather than going into the atmosphere. Ocean currents mix the surface water with water in the depths, distributing the oxygen all the way to the bottom. This process goes on continuously. Oxygen is very reactive. Oxygen gradually combines with other elements to make minerals. If contamination kills the seaweed and plankton or keeps sunlight from reaching the surface, eventually there will be insufficient oxygen to sustain life near the deep-sea vents.
Knowing thermodynamics and the role of chlorophyll in sustaining life allows us to evaluate the idea some NASA people are advancing, that they may find life under the ice of Europa, one of the moons of Jupiter.[i] Europa possibly has liquid water layers under its frozen surface. The powerful gravity of Jupiter may cause tidal effects strong enough to heat and melt some subsurface parts of the ice. The overlying ice layers may supply the pressure water needs to keep from boiling away. But the water under the ice layers will not have any dissolved oxygen in it. Even if photosynthesis or some other process made free oxygen from the weak sunlight incident on Europa’s surface, the oxygen could never work its way down through the surface ice into the liquid layers below.
Surely NASA has scientists who know what we just explained above. Certain budget dynamics keep NASA scientists from gross sensationalism. The problem is that the possibility, however far-fetched and evanescent, of finding alien life is so sensational that it bypasses reasonable scientific caution and leads the popular mind astray.
[i] Johnson, Torrence V., “A Look at the Galilean Satellites after the Galileo Mission,” Physics Today, 57 (Number 4, April 2004), pp. 77–83.
Knowing thermodynamics and the role of chlorophyll in sustaining life allows us to evaluate the idea some NASA people are advancing, that they may find life under the ice of Europa, one of the moons of Jupiter.[i] Europa possibly has liquid water layers under its frozen surface. The powerful gravity of Jupiter may cause tidal effects strong enough to heat and melt some subsurface parts of the ice. The overlying ice layers may supply the pressure water needs to keep from boiling away. But the water under the ice layers will not have any dissolved oxygen in it. Even if photosynthesis or some other process made free oxygen from the weak sunlight incident on Europa’s surface, the oxygen could never work its way down through the surface ice into the liquid layers below.
Surely NASA has scientists who know what we just explained above. Certain budget dynamics keep NASA scientists from gross sensationalism. The problem is that the possibility, however far-fetched and evanescent, of finding alien life is so sensational that it bypasses reasonable scientific caution and leads the popular mind astray.
[i] Johnson, Torrence V., “A Look at the Galilean Satellites after the Galileo Mission,” Physics Today, 57 (Number 4, April 2004), pp. 77–83.