Letʼs look at some of the questions that arise for those who would contend that the cosmos was designed so that they in particular, in all their individuality, would come into existence…
During childhood a girlʼs ovaries absorb almost half of the 1,000,000 immature eggs with which she was born. Of the 400,000 eggs present during her first menstrual period, only 300 to 500 of them will develop into mature eggs across her reproductive life span. Her body reabsorbs the rest before they complete development. In similar fashion the vast majority of sperm go unused, many are deformed, i.e., two heads, two tails, squiggly tails, heads that are too large or two small. Sperm are also subject to physical stress during ejaculation and contractions of the female tract, and may sustain oxidative damage, or even encounter the defenses of the female immune system meant for infectious organisms. Of the millions of sperm inseminated at coitus only a few thousand reach the Fallopian tubes and some travel up the tube through which an egg is not descending. So the odds of any particular sperm reaching any particular egg keep diminishing via the most insignificant turns of events. All “meticulously designed?” And why the perishing of so many unused eggs and sperm as part of the “design?”
A similar question is why the perishing of so many early apes and other primates prior to the arrival of the sole surviving species of homo? Why the perishing of endless species before them like extinct species of monkeys, and prior to them the plethora of extinct species of lemurs? Etc., going back in geologic time.
Neither is the vagina “sperm tight.” In fact, in a 5 year study of 11 female volunteers Baker and Bellis (1993) examined the characteristics of sperm loss from the vagina following coitus (‘flowback’). They found that flowback occurred in 94% of copulations with the median time to the emergence of ‘flowback’ of 30 min (range 5—120 min). Furthermore they estimated that a median of 35% of spermatozoa were lost through flowback but that in 12% of copulations almost 100% of the sperm inseminated were eliminated. This suggests that less than 1% of sperm might be retained in the female reproductive tract and this supports the notion that only a minority of sperm actually enter cervical mucus and ascend higher into the female reproductive tract.
Some sperm have just the male compliment of genes, some the female compliment. The male-producing-sperm tend to be faster on average, but the female-producing-sperm tend to be stronger on average, so itʼs a stalemate in the sperm gender competition to fertilize the egg. Itʼs anyoneʼs race. One might certainly take the above data as evidence that you as an individual were the result of the toss of genetic dice.
Even the circumstances by which oneʼs parents meet, and the time of year or day they make love, and the position they are in when they do so, along with other circumstance, can affect which sperm reaches which egg.
See Infographic, “The Odds of You Becoming You.”
My point is that nature raises more questions than answers. We do not appear to live in a cosmos that “guarantees” life will “succeed.” It looks like a big tinkering job if it takes so many suns and planets to keep mixing so many types of energy and matter for so long until a planet arises with self-replicating molecules on it. And no individualʼs life appears “guaranteed to succeed,” nor even the life of our species. Cosmically and geologically speaking, our species just arrived on the scene, and it has had several close calls (genetic bottlenecks, barely surviving the Ice Ages), as have many other species throughout time, the majority of which did not make it to the present. Nor do we know how much time our species has left. “Here today, gone tomorrow” might be humanityʼs epitaph.
Letʼs look deeper at what we know about human life. Up to the mid 1700s half of all children who were born died before reaching the age of eight (according to Buffonʼs estimate). Most fertilized human eggs [zygotes] abort during the first weeks of life. Estimates of death before implantation range as high as 80% and bottom out around 45%. More than 30% percent of those that do implant die before being born. Even among single births, 20-30% of them used to be twins in the womb but one twin absorbs the other, or is absorbed by the womb (vanishing twin syndrome). This means that sex produces on average, more zygotes, embryos and fetuses that die rather than survive. Someone like Michelle Duggar with her 19 children who does not use birth control, could not avoid having lost double or triple the number of fertilized eggs which she was able to carry to birth. She lost anywhere from 17 to 75 fertilized eggs in order to get the 19 children she has. Thatʼs a pretty big loss for every fertilized egg that made it to birth. Thatʼs how “design” works apparently.
And letʼs not forget that “designs” are constantly competing against other “designs.” Nature is opportunistic and jury-rigged all the way down. If the viruses and bacteria canʼt eat the human, some of them live on it or inside it in benign fashion, while others life on or inside the human in a semi-beneficial fashion, and others in a fully symbiotic and mutually beneficial fashion. But words like “harm” and “benefit” are mere metaphors, relative to each species. Itʼs all the same to nature, since every organism is reaching out to whatever is at hand to feed itself and continue churning out more of itself.
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