A few days ago, I had minor surgery. Even these minor surgical procedures require preoperative tests, such as the coagulation test (or clotting test, if you will).
The reason for this test is to identify whether the person’s blood has the ability to clot, and, therefore, to figure out if the person can be subjected to moderate bleeding without any risks for his or her life.
As we know, coagulation is the process by which the liquid blood becomes solid in cases of bleeding, to prevent the body to bleed into death.
What happens is that when a person suffers a cut, that is, whenever there is disruption of a blood vessel, a process takes place: blood platelets, coagulation proteins, and other elements get into action to stop the bleeding by promoting the creation of a clot.
What few people know, however, is that the coagulation is extremely complex, functioning as a chain reaction in which the platelets activates the process and release the blood clot proteins (called coagulation factors) to initiate a series of chemical reactions.
Twelve types of proteins are involved in the clotting process. They are named only numbering them as follows: Factor I, Factor II, and so on, until we got to factor XII.
It is important to know that it is the activation of Factor I that leads to the activation of Factor II; it is the activation of Factor II that leads to the activation of Factor III, and so on until we reach the Factor XII and, therefore, the clot will be able to appear.
Without these factors, there is no coagulation and the person will bleed to death.
There is a genetic disorder (an inherited one) in which certain people are born with disabilities in the activity of Factor VIII or IX. This is called hemophilia, which is divided in type A (problem is in factor VIII) and B (problem is in factor IX). These people have in their bodies a greatly reduced activity of these factors, this is why they require special care.
You may now be wondering what all this has to do with evolution. The point is that the clotting process in humans contains what is called irreducible complexity. Not only the twelve factors are essential, but they also have to occur in a specific order.
That is, a coagulation process would be completely useless without only one of the twelve factors because there would be no clot at the end of the process. In other words, any less complex clotting process would be useless in a living organism.
What is important to know is that it is an obstacle to the evolutionary idea that less complex organisms can gain great amount of complexity only by a natural processes.
According to the logic behind Neo-Darwinism (mutation by chance plus natural selection), any less complex versions of the blood clotting process would be automatically discarded by natural selection, as it would not bring any competitive function at all.
The most plausible explanation is that organisms came to existence already in their levels of complexity and according to their genetic pools, as advocates the Christian Holy Scripture.