In all of our experiences, death accompanies life. But what if that weren’t so? What if death never terminated the existence of some form of living organism? For example, simple, single-celled bacteria reproduce asexually through binary fusion, with a doubling time as short as 30 minutes or less. If such bacteria remained untouched by death, their population would increase exponentially.
Currently, it’s estimated that 5 x 1030 bacteria (of all kinds) exist on Earth (outweighing the total human population by about ten thousand times!). It’s astounding to consider, but without death, a single bacterium through cell division could multiply to this number in about eight and half days. Eliminate death, and in just three more days the bacteria population would outweigh the entire planet! As nightmarish as this sounds, we don’t have to panic, since resource limitations and other factors effectively act to stave off this disaster.
Life Without Death
Biological life without death can quickly get out of control for more complex species of life as well. Mice can have a growth rate of 100 percent per month. What does this translate to if death is eliminated? Well, in just under three years, the number of mice would multiply so drastically that there would be over three mice for every square foot of land on Earth.
Continued human reproduction without death would also overwhelm the planet. A single human pair, producing another human pair every 30 years (and so on for their offspring), would reach a population of one trillion in less than two millennia! This number is 125 times the current population of the whole Earth, and would arguably lead to unsustainable consequences.
So, what can we make of these outcomes? It seems that if life without death means unceasing reproduction, then trouble ensues. While humans might be able to cognitively limit reproduction, this seems a tall order for non-human life in the world as we know it. To avoid being overrun by bacteria, mice, or other creatures on Earth, death seems essential.
We commonly regard death as evil, an aberration. It’s worth pondering why we perceive death in this way, when it is so common to us by knowledge, if not by experience. Does our reaction to death suggest that it is an aberration in our original design? The biblical narrative presents just such a scenario. The entrance of death into the human experience is described as a departure from the original intent for humans.
The Need for Reproduction
With biological death comes the need for reproduction; or as shown in the examples above, with reproduction comes the need for death. Living creatures are complex in myriads of ways, not the least of which is their reproductive ability. The unique qualities of plant and animal life, awesome in beauty, and fascinating in their attributes, strike us as whole, complete, and right. So, it often hits us hard to see living things die.
Just the other day, as my wife and I were enjoying our morning coffee on our back patio, a busy squirrel was entertaining us high up in the branches of a tree overhead. Suddenly it lost its grip and fell more than 30 feet to the ground, landing with a thud not more than three yards away from us. As our cat sprang towards this unexpected “windfall,” it jumped up and scampered back up the tree! In the few seconds it took for these events to transpire, our emotions ran the gamut from dismay, to surprise, to relief.
I can say that it seemed “right” to watch the squirrel being busy in the tree, and it seemed viscerally “wrong” for it to fall to its death at our feet. Seeing it after a few minutes coming back down the tree and vigorously scolding our cat brought us welcome humor to ease the sudden stress of seeing it fall.
Recruited to Serve Life
Despite our aversion to the death of living things, we note that death is recruited to serve life throughout nature. Seeds are collections of cells that remain unproductive unless they are planted in the ground, and then the cells undergo a transformation of growth until a full-grown plant arises and matures to produce many new seeds of its own. Ecosystem sustainability depends upon a balance of the life cycles (from birth to death) of all the inhabitants of the system. One could possibly imagine a unique ecosystem in which death is restrained, but then the ecosystem could only continue to thrive without the ongoing reproduction of its various life forms.
Design features appear in the balance between the reproductive rate of a living thing and its longevity. Typically, with short lifespans, the reproductive rate is high, and vice versa.
The tradeoffs between lifespan and fecundity are universal in the biosphere, ranging from microorganisms to plants and to animal kingdom, including humans. While the mechanisms of the tradeoffs are still an enigma, it is critically important to maintain the diversity and balance of the biosphere for the existence of species.
An Element of Mystery
Even the death of cellular life has an element of mystery to it. The process of normal cell division is curtailed by a limited number of DNA segments called telomeres attached at the ends of each chromosome.
The number of repeats [of telomere segments, defined by the nucleotide sequence TTAGGG] determines the maximum life span of a cell: each time a cell undergoes replication, multiple TTAGGG segments are lost. Once telomeres have been reduced to a certain size, the cell reaches a crisis point and is prevented from dividing further. As a consequence, the cell dies.
Emphasizing the importance of this process for the overall health of the living creature is the fact that normal cells can become cancerous if the lifespan-limiting telomere reduction process is shut down. So again, we see design in the restriction of unbridled replication of living cells. It’s not hard to see the irony in imagining an evolutionary explanation for the death of cellular life. Instead of survival of the fittest, it’s survival by death. Selective cell death contributes to the life of the organism.
If the origin of a self-replicating cell is difficult for unguided nature to produce, how much more incredible is it to expect “programmed cell death” to occur naturally. In fact, research suggests that only the opposite process — uncontrolled cellular replication — is attainable as an evolutionary outcome.
Dr. Casey Luskin has recently reviewed two peer-reviewed papers by Dr. Karl Krueger, a former manager of cancer research at the NIH’s National Cancer Institute, showing that cancerous tumor development results from a “devolution” of cell replication and proliferation of regulatory mechanisms.
Krueger’s two papers are highly consistent with Michael Behe’s “Darwin Devolves” thesis: mutations tend to break features at the molecular level. In cancer, this often involves breaking mechanisms that are designed to inhibit the activity of key genes, and when those mechanisms are broken, out-of-control cell growth results. Yes, cancer is a Darwinian process — but what it reveals is that at the molecular level, the Darwinian mechanism typically works by breaking features, not by creating new ones.
In this brief reflection, we’ve reasoned that limited lifespans, accompanied by reproductive continuation of the living organism provide a sustainable balance for life, subject to the constraining conditions of Earth. Intelligent design is evident when considering the complexities involved not only in the origin of life, but in governing its proliferation. While the biblical narrative points to original conditions without the rule of death, we can be thankful for evidence of design that prevails even in our experience of life and death.