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What the Body Must Do to Take Control

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Editor’s note: Physicians have a special place among the thinkers who have elaborated the argument for intelligent design. Perhaps that’s because, more than evolutionary biologists, they are familiar with the challenges of maintaining a functioning complex system, the human body. With that in mind, Evolution News & Views is delighted to present this series, “The Designed Body.” For the complete series, see here. Dr. Glicksman practices palliative medicine for a hospice organization.

To survive, our body needs many different atoms and molecules, like oxygen, water, salt, and sugar. When we feel the urge to breathe, our body is telling us it needs more oxygen, right now. When we feel thirsty, our body is telling us that it will need more water soon. And when we’re hungry, our body is telling us that it could use more salt, sugar, or both in the near future. Our body’s ability to tell us when we should breathe in air, drink water, and eat food means that it must have a way of determining what it needs to live. Moreover, experience shows that, by necessity, our body must be able to take control of its chemical content and physiological functions. But, how does the body do it?

the-designed-body4.jpgTo be able to control something this way requires having at least three different parts all working together in perfect harmony. The first thing you need is a sensor to detect what needs to be controlled. If you have no way of being aware of what needs to be controlled, how can you control it? The sensor is like the reconnaissance team that an army sends out to check on the whereabouts and activities of its enemy. Without this sensory information the army would be in the dark and would have no way of taking control of the situation.

The second thing you need is an integrator which interprets the information from the sensors, compares it to a standard, makes decisions about what needs to be done, and then sends out orders. If you don’t understand the information from the sensors, don’t have any idea about what is required, and can’t make decisions about what should be done or send out orders, then what use are your sensors? The integrator is like army headquarters where the information from the reconnaissance team is analyzed, compared to the strategic plan, decisions are made about what needs to be done, and orders are sent out. Without this work of integration at HQ, there would be no coordinated action in the field and, again, no way of taking control of the situation.

The third thing you need is an effector which receives the orders from the integrator and does something. If you have a sensor to detect what needs to be controlled and an integrator to know what needs to be done and sends out orders, but not an effector to take those orders and do something, then what’s the use of having the first two? The effector is like the soldiers who, at the orders received from headquarters, go and do what needs to be done. Without soldiers to take effective action, the battle is lost.

In my previous post in this series ("Death: The Final Frontier"), we observed that a car needs gas for it to run properly. Let’s see how the operator of a car takes control to make sure it doesn’t die in the middle of the road. Gas is the fuel that provides energy to the engine so the car can move down the road. Obviously, it’s important for the driver to be aware of her car’s fuel situation. Recall that to take control you first have to be able to detect what needs to be controlled. The car’s manufacturer provides a sensor in the fuel tank to detect the level of gas present.

The sensor must not only be in the right place and be designed to sense what needs to be controlled, but the information it provides but also reflect the true situation. If the fuel sensor were to be placed in the car’s cooling system, rather than the fuel tank, it wouldn’t help the driver much. And if a sensor designed instead to detect temperature were placed in the fuel tank, rather than one that can detect gas, the driver again would be in trouble.

Finally, if the fuel sensor isn’t working or isn’t calibrated properly then the information the driver receives about how much gas she has is going to be incorrect. So, for the body to take control of its chemical contents and other important physiological functions, it must first have properly working sensors located in the right place(s) that are specific for what needs to be controlled.

Recall, too, that to take control the second thing you need is something to integrate the information from the sensors by comparing it to a standard, making a decision about what needs to be done and then sending out orders. The car manufacturer provides a fuel gauge that is located on the dashboard so the driver can easily see it. The fuel gauge is calibrated to show how much gas is in the fuel tank. By looking at the fuel gauge the driver knows how much gas is left in her tank and she can make a decision about what needs to be done.

As noted above, it’s important to realize that the integrator must not only receive data from the right sensor(s), but must also get the right information so the right decision can be made. If the fuel gauge received data from the temperature sensor in the cooling system, rather than from the fuel sensor in the gas tank, the driver would be misinformed about her fuel situation. And if the fuel gauge isn’t calibrated properly so that it is showing, for example, that the fuel tank is half full, when in reality it is almost empty, then the driver is likely to run of out gas by mistake. So, for the body to take control of its chemical contents and other important physiological functions, its sensors must send their data to the right integrators, where it is analyzed correctly, the right decision is made about what to do, and the right messages are sent out to get it done.

Once a decision is made, to take control, and a message has been sent out, the third and final thing you need is something to take effective action. When the driver sees that the fuel gauge is showing that her car is running out of gas she must stop the car at a gas station and put gas in the fuel tank. Not just any action will result in effective control. If instead of gas, the driver pours antifreeze into her fuel tank, or she pumps the gas into the radiator instead of the fuel tank, the car will not work properly. So, for the body to take control of its chemical contents and other important physiological functions, once the sensors inform the integrators, and the integrators decide what must be done and send the right messages, the effectors must do the right thing(s).

Now that you know what is required to take control (sensor, integrator, effector), we’ll consider in a general way what the body uses to take control of its chemical contents and physiological function. But remember that not only are each of these systems more complex than keeping enough gas, oil or anti-freeze in your car — if any one of them were to be absent or were to malfunction, then death would take place, just like with a car. Finally, remember that evolutionary biologists expect us to believe that this all came about through chance and the laws of nature alone.

Image by By Thomas Doerfer (Own work) [GFDL or CC-BY-SA-3.0], via Wikimedia Commons.