Editor’s note: We are delighted to offer the series “Modernizing Darwin,” cross-posted at Shabbat.com, by Geoffrey Simmons, MD. Dr. Simmons is the author of What Darwin Didn’t Know and Billions of Missing Links. He is a Fellow with Discovery Institute’s Center for Science & Culture.
Like a well-written, trillion-page novel, every micro-step, every macro-step, every twist and turn of our development follows a master plan. Any deviation, at least early on, from the blueprint would be like building a skyscraper and leaving out important parts of a first floor. Trillions of coordinated actions are linked together in time and space to create a human being. Quadrillions of very specific chemical reactions happen in sequence and/or in tandem.
Everything is perfectly timed. Virtually nothing is left to chance. Intelligent design requires intelligent planning.
From a Single Cell
The single cell (a zygote), formed by the union of the egg and sperm, becomes a 15 trillion-cell individual in a matter of nine months with amazing precision and speed. That includes over tens of thousands divisions per second with a greater than 99.99 percent rate of accuracy. By the 16th day the heart starts beating. By 30 days, the embryo will have grown to 10,000 times the size of the fertilized egg. At seven weeks the unborn child is an inch long and has developed all organs (e.g., liver, sex organs, spleen, intestine). At eight weeks, fingerprints and toe-prints can be found and the brain and spinal cord are clearly present. At a specific time, 250,000 neurons (nerve cells) migrate (climb, crawl, swim, slide, squeeze by) every minute to designated places with distinct purpose(s) within the brain. Compared to their size, the distances traveled by some can be compared to humans walking many miles. Noted the 15 trillion will become 75 trillion by adulthood.
At twelve weeks vocal cords show up, but because the lung are still filled with amniotic fluid and not air, a voice and breathing are absent. At four months ultrasound can show the baby sucking its thumbs and playing with its umbilical cord. Between 18 and 20 weeks the senses for pain are mature, virtually the same as they will be at birth. Studies show babies withdrawing their feet in response to irritating stimuli.
A few premature babies at around 23-24 weeks can survive in a neonatal intensive care unit. At 24 weeks, ultrasound can show the baby smiling. At twenty-eight weeks, a baby will track a moving light, such as a flashlight, held against the mom’s belly. Somewhere in this period, the baby learns to recognize her mother’s voice.
Time to Greet the World
When the baby decides it’s time to greet the world, she sends millions of messenger chemicals to the mother’s brain saying, “I’m ready. How about hitting the START button?” Mom’s brain then floods the womb with a different set of chemical messages telling all cells there to start the warm-up process. That mostly means contractions. There’s a shifting and aiming of the baby’s head downward and the placenta is notified to start loosening its grip. Of note, by this time, the uterus is 5 times its usual size, has a capacity of 500 times normal, and weighs in at 15 times heavier. It will return to normal size within a week, but it takes another month or so for complete healing.
The start-up contractions are called false or Braxton Hicks contractions; about this time a small amount of amniotic fluid leaks occurs (“my water broke”). The first contractions are variable in timing and usually mild, but that soon changes to closer timing and increasing intensity (pain). Pressure also comes from the sides of the uterus to line up the baby. An extremely thinned uterus does the pushing.
The baby has to exit to the outside world through the cervix which normally looks a little like a soft, pink bottle cap with a tiny hole in the middle (where the Pap test is done). This opening will slowly dilate to ten centimeters (4.5 inches) before the baby can begin its outward journey. As it moves, its head fits inside (“engages”) the canal, facing sideways. Sideways is critical. The passageway through the bony pelvis is not wide enough to accommodate our large head (and large brain). FYI: The great apes don’t have this problem. Despite their size, their brains are considerably smaller.
No Room for Experimenting
Four percent of the time, the baby presents feet first or breech. The reason for this is unknown.
The instant the baby passes out of the womb, chemical messages tell the baby’s brain to start the lungs breathing. There’s no obvious ON switch, START button or pull cord, but some critical mechanism(s) has to exist. Perhaps, it’s temperature change, air pressure change, and/or the hint of oxygen tickling the baby’s nose. We don’t know, but this messaging is obviously critical. A swat on the butt is more for the movies. If breathing starts too soon, the baby dies of asphyxiation; if too late, the baby incurs brain damage or dies of hypoxia (low oxygen). The decision to start breathing happens in a matter of seconds. It has to be exactly timed. Childbirth has always been this way.
There’s no room here for nature to have experimented.
On occasion, an unborn child will linger part way through the birth canal for hours, even days, especially with the mom’s first pregnancy, yet the baby remains quite stable, without a need to breathe.
By Survival of the Fittest?
At the time of birth, the newborn’s blood, which had been circumventing the lungs for nine months (there was no reason to breathe), must immediately go through lungs to absorb oxygen. There’s a very interesting trick (or change) that happens promptly after birth. A valve-like artery (ductus arteriosus) that was used to bypass the previously dormant lungs (since oxygen came from the mom via the placenta) closes off while the arteries to the lungs become functional. The lungs’ tissues are ready to roll. The timing has to be exact. The rare baby who survives the non-complete closure of the ductus will need urgent surgery to close off this artery.
The birth of a baby could not have come about by survival of fittest, which is to say, by nature’s experimentation or trial and error. Mutation would have made things more dangerous. Intelligent planning is seen throughout.
Photo credit: Claire51700, via Pixabay.