The human body is an engineering marvel – an amalgam of interlocking chemical and engineering solutions – with dozens of diverse, interdependent control systems driving hundreds of functional subsystems, composed of tens of thousands of specialised parts, and comprised of approximately 37 trillion individual cells. Each cell is itself an engineering marvel, comprised of thousands of interdependent parts, precisely arranged and coordinated in their actions. To make this work, the human body generates around 200 specialised cell types and well over 10,000 specialised proteins. All this “unfolds” from a single cell at fertilisation, in a precisely choreographed process.

This is not gratuitous complexity. There are at least 40 chemical and physiological factors that are essential for life. These processes work together in complete unity and depend on each other for the right outcome. They even have failure prevention systems to detect and defend against threats, correct errors, and keep everything working.

Only when all the parts operate as a coherent whole does the body survive. If one of these mechanisms was not in place, the body would soon fail to live. Coherence is difficult to achieve and maintain under any circumstances, but survival of the human body takes functional coherence and interdependence far beyond our experience as human engineers.

At the same time, coherence and interdependency makes change more difficult. If evolution is at work, changing one part of the body over millions of years, it would require significant changes to all other dependent processes elsewhere. If a lock and key arrangement in a cell is still under development through evolution then there can be no transfer of essential proteins until the mechanism works and that has a knock-on effect through the whole system dependent on that cell’s vital function.

How does a complex functioning body come into existence and survive? For example, how do you supply oxygen to every cell in a large, complex body without every part of each required body sub-system being present (eg for oxygen exchange, carbon dioxide removal, circulation, iron harvesting, haemoglobin manufacture, and many more).

How many generations would survive without the correct control logic and just the right fine-tuning? Exactly zero, since no individuals will survive long enough to reproduce, and any gradual steps toward a functional whole would disappear from the population.

How does an individual made up of complex parts come into existence? At the moment of fertilisation, the human body consists of a single cell. As it grows into thousands and then to hundreds of millions of cells, it must “bootstrap” the control systems for all 40 survival factors. As it’s developing its internal controls, this new life is extremely vulnerable to the forces of nature, so it must rely on outside help to survive. With humans this occurs in the mother’s womb. In this extraordinary process, the mother and unborn child coordinate their activities, such that the mother’s systems “cover for” the growing child’s inability to control all the necessary survival factors.

Only when all of its internal control systems are assembled and functioning can the child survive on its own. At the right time, through “coordinated signalling”, birthing occurs and the child’s body switches over to its internal systems to perform their survival chores (eg respiration).

It’s important to note that this process involves two different individuals, using completely different yet perfectly integrated mechanisms, at two very different points in their life cycles. If the mother is still evolving how can she produce children without the processes to keep them alive? If the child is still evolving how does it take advantage of the mother’s essential life-supporting systems? Either both individuals work together or nothing works.

Coherence is thus a prerequisite for life; not the outcome of life, as Darwin supposed. This simple fact is profoundly problematic for material causation. Gradual changes simply cannot produce such systems. Neither can random causes. How much more gratifying is it to believe that we are “fearfully and wonderfully made”.