Since the issue of the small brain size came up, this is a good time to talk about the two curses God put on the primal parents :
Eve's curse and brain size extracted from here
Glenn R. Morton April 25,2020
Above I have spent some time defending the big brained scenario for what species Adam and Eve were. Some people might prefer that view. Below, I am going to use a Biblical reason for why I believe Adam and Eve had a brain-size about half our present value or smaller.. At this point I am shifting to look not at the scientific evidence but at the Biblical evidence.
I think one of the interesting possible interpretations of Scripture has been totally overlooked for millennia. Most didn't have the scientific knowledge to understand what it said, but for the past 100 years we have and no one seems to have seen it.
Both the woman's curse and the man's curse in Genesis 3 involve a future big brain!
Most liberal Christians (defined as not believing there is any scientific/historical information in Genesis 1-4), place Adam within the past 10,000 years. Such a position for Adam makes an utter laughing stock of everything done and said in Genesis 3. That is, assuming they believe Adam was an individual rather than a population. I call this the Johnny-come-lately Adam because he is really too late in time, even by Biblical evidence. Let's look at some of the things Johnny- come-lately Adam is too late for.
Sally-come-lately Eve is too late for pain in childbirth to mean anything.
Pain in Childbirth Genesis 3:16:To the woman He said, “I will greatly multiply Your pain in childbirth," (NASB)
If someone cursed me right now with having trouble walking, it would mean nothing. I already HAVE trouble walking from side effects of a drug trial. Or if they cursed my hair to turn gray when it is already gray, or as a friend said, 'it would be the same as if He cursed you with ugliness." LOL, So, big deal.
That must be how Sally-come-lately Eve felt when God told her she would have increased pain in childbirth. Sally-come-lately Eve would say: "Big Deal. Big Guy! Haven't you heard millennia of screaming women in labor who are cursing what their husbands did to them?" Thus, the curse is no curse at all!
Further Gen 3:20 says Eve was "Mother of all living." Sally-come-lately Eve certainly couldn't have been the mother of all the other women alive with her, 10,000 years ago in the Neolithic. Nor could she be the mother of all living until maybe the last century or two. Why? The other day I spoke about Tasmanians being isolated from the rest of humanity from about 12,000 years to 1642 AD.(
1) To say Eve was the mother of all living 10,000 years ago would have been a farce, yet that is what the liberal position on Genesis does to it. It makes everything a farce. Let's go back to looking at the pain in childbirth issue.
Pain in childbirth arises from the size of the baby's head vs the size of the birth canal. Bipedalism requires that the legs be close enough together so that the person can walk without a waddle. But this causes the pelvic opening to be small. Intelligence requires large brains and thus large cranial sizes. These two conflicting features lead to the tight fit of the infant through the birth canal. Wendy Trevathan wrote a book advocating that the problems relating to human deliveries and produced selective pressures which led to the nearly universal human practice of midwifery. Further, the change from the ape style birth to the human style birth required that the large brained infant be born prematurely and spend much of what would be neonatal time outside the womb, increasing the intelligence of the infant, who has a world of sensory perception while the brain is developing.
"
The human pattern of pre-and post-natal brain growth and development is very unusual relative both to other mammals and to other primates. At birth, human babies' brains are small--only about 30% of their adult size, as opposed to about 50% in other primates--although their gestation time is long for an animal of their body size. Unlike other living species, humans maintain the pre-natal rate of brain growth for approximately a year after birth, resulting in an unusually large brain size relative to body size."
(2)
Basically we are born a year too early. Most other primates with small brains, give birth to infants with brains 1/2 of the adult size, but if humans did that, no woman would be able to walk, or, alternatively no child would survive birth. Thus, human infants are born with brains 1/3 the size of the adult and yet still it is a tight fit through the birth canal.
"
A modern human baby, with its large skull, negotiates the birth canal by entering with the head oriented transversely. It then rotates 90 degrees into a sagittal position before exiting the canal facing the sacrum, that is, with its back toward the mother's face. A human mother is therefore in a bad position to assist in delivery, since her infant is exiting 'down and back,' away from her helping hands. Furthermore, pulling an emerging human infant up toward the mother's breast would bend it against the normal flexion of its body and would possibly result in injury. Interestingly, the human delivery pattern is very different from that of nonhuman primates, in which there is no fetal rotation (babies are sagitally oriented throughout birth) and newborns exit the canal face-to-face with their mothers. In this pattern, mother monkeys and apes routinely assist in delivery by reaching down and pulling emerging infants up and toward their chests in a curve that matches the normal flexion of the babies' bodies."
(3)
So monkey and apes can pull their own babies out of the birth canal, human mother's can't. they need help in bad situations. How long has this birth pattern been in existence? At least since the time of H. erectus 1.6 million years ago . The famous Lucy (AL 288-1) didn't have this problem. Ruff comments.
"
It has been cogently argued by Tague & Lovejoy (1986), based on the obstetric pelvis of AL 288-1, that birth in Australopithecus afarensis would have occurred with the fetal cranium in a transverse orientation throughout, i.e., without the pelvic rotation characteristic of modern humans, and that secondary altriciality of the infant need not have been present. In contrast, based on the relatively small size of the birth canal of KNM-WT 15000, it has been argued that secondary altriciality must have been present in Homo erectus, i.e., that the infant must have been born in a relatively helpless state. Furthermore, the anthropoid shape of the pelvic inlet/outlet in this male juvenile, even allowing for growth to adulthood and sexual dimorphism in pelvic shape, indicates that a transverse non-rotational birth mechanism would have been highly improbable." (4)
Because of this data, it makes much more sense that Eve have been a small brained hominid because otherwise there is no meaning to the curse of increasing her pain in childbirth. She would have already had it.
Now to tie up the final item, pain in childbirth. Among mammals there are two patterns of brain growth. The first pattern is called altriciality. In this pattern the animal is born helpless and extremely immature. The brains of altricial animals are usually half the size of the adult's, and double in size by adulthood. Because of this it takes lots of parental effort to raise the young. Animals following this pattern usually have litters and perform this care for multiple offspring at once. Cats, with their blind and helpless kittens are altricial. The other pattern is precocial. In this pattern the offspring are usually born single and from birth are able to get around quite well. Their brains are nearly adult size at birth. The are alert and all their organs are functioning. An example of this pattern is the horse, the wildebeest etc., where the young will run with the herds within minutes.
Now, according to Walker and Shipman
(5), altricial species almost never have bigger brains than precocial species. The reason is that for all mammals save one, the brain grows rapidly during gestation but then grows less rapidly after birth. There is a kink in the graph of brain size vs. time which occurs at birth. Altricial species whose immature state at birth and subsequent slow down in the rate of growth forever remain behind the more maturely born precocial species.
What humans seem to have accomplished is the trick of keeping the brain growing at the embryonic rate for one year after birth. Effectively, if humans are a fundamentally precocial species,
our gestation is (or should be) 21 months. However, no mother could possibly pass a year old baby's head through the birth canal. Thus, human babies are born "early" to avoid the death of the mother. Walker and Shipman write:
"
Humans are simply born too early in their development, at the time when their heads will still fit through their mothers' birth canals. As babies' brains grow, during this extrauterine year of fetal life, so do their bodies. About the time of the infant's first birthday, the period of fetal brain growth terminates, coinciding with the beginnings of speech and the mastery of erect posture and bipedal walking."
(6)
This pattern of growth has huge implications. Every other primate doubles their brain weight from birth to adulthood. But due to the early birth of humans, we triple our brain's birth rate. Our last 12 month of fetal growth rate of the brain occurs outside the sensorially deprived womb. The vast quantities of sensory input during the first year of life affects the rate and nature of the neural connections. Because of this year of helplessness, parents must provide close physical and emotional support for the infant. Unlike chimp babies who can cling to their mother's fur, human infants cannot even hang on to mother in spite of having the hand reflex. The mother has no fur because she sweats and she sweats because of a big brain which is why she gives birth to her child early. This early birth then requires the mother to care for the infant and increases the bond between mother and child which partially makes us human.
So, what is the birth pattern in Homo erectus? It is human. Shipman and Walker(7) point out that the adult Homo erectus cranial capacity was 950 cc. If they followed the ape-like pattern of doubling their brain size after birth, they would need to be born with a brain size of around 400 cc. Following the discovery of a nearly complete Homo erectus skeleton, the approximate size the erectus birth canal is known. A head with a 400 cc brain is 10 cm too big to fit through the birth canal. Estimates place the maximum fetal brain size able to fit through the erectus birth canal at just 231 cc
(8). Homo erectus had a human pattern of birth and must have endured similar pain in childbirth.
A study of
Homo rudolfensis which lived eight hundred thousand years earlier than the 1.6-million-year-old Homo erectus studied by Walker and Shipman above, also had a human birth pattern of trebling its brain size from birth to adulthood.
Homo rudolfensis stood about 5 foot 8 inches tall and was quite human in form below the neck
(9). Steven M. Stanley showed that the birth canal of a
Homo rudolfensis would only be able to pass a fetal head of about 210 cc. The adult of this species had brain sizes in the range of 760 to 900 cc. This data would strongly imply that pain in childbirth of the type experienced by human mothers extends back at least 2.4 million years to the initial appearance of Homo rudolfensis.
(10) The birth pattern means that
Homo rudolfensis children would also be born as helpless as any human or erectus baby which would require long periods intensive care. This would lead to an intense period of bonding between mother and child as also occurs among humans. And the enlarged brain would most likely have meant hairlessness among the
rudolfensis also. In short, this birth pattern means they had many of our traits which are theologically associated with the Fall.
To close, it would appear that there is a single underlying cause of God's curse for the man and woman and it is an increase in brain size. This increase also caused the loss of hair requiring clothing when mankind eventually inhabited northern climes. Homo erectus is found in European Georgia 1.6 million years ago. Without fire or clothing, he would have been unlikely to survive the more severe winters in that area.
The fact that Homo erectus and
Homo rudolfensis were saddled with the problems given to Adam and Eve after the fall has theological implications for the status of
Homo erectus and
Homo rudolfensis, the time during which Adam lived as well as who is eligible for salvation. I have long contended that humanity in the theological sense is much older than most Christians are willing to admit. If sweat and increased pain in childbirth and clothing are not signifying of humanity and the Fall, what then does theologically separate us from mere animals?
It is also intriguing to me that the ancient Hebrew writer would choose as a curse for man and woman, two different maledictions which can be caused by a single phenomenon--an increase in brain size. This single cause also would require the loss of hair and the subsequent need for clothing. There is no way that the Hebrew writer could have had the knowledge to purposefully construct this tale. Is this a fortuitous conjunction of statements or is it divine inspiration? I firmly believe God inspired the writer and while he didn't understand it, we can today.
References
1 Jared Diamond, “The Evolution of Guns and Germs,” in Evolution: Society, Science and the Universe, ed by A. C. Fabian, (Cambridge: Cambridge University Press, 1998), p. 602.
2P. Shipman and A. Walker, "The Costs of Becoming a Predator," Journal of Human Evolution, 18, 373-392, p. 385.
3.Bernard G. Campbell and James D. Loy, Humankind Emerging, (New York: HarperCollins, 1996), p. 272
4.Christopher B. Ruff, "Climate and Body Shape in Hominid Evolution," Journal of Human Evolution (1991), 21, 81-105, p. 93
5. Alan Walker, and Pat Shipman, 1996, The Wisdom of the Bones, (New York: Alfred Knopf). , p.220-222
6. Alan Walker, and Pat Shipman, 1996, The Wisdom of the Bones, (New York: Alfred Knopf), p. 222
7.Shipman, P. and A. Walker, 1989. "The Costs of Becoming a Predator," Journal of Human Evolution, 18, 373-392, p. 388-389
8. Alan Walker, and Pat Shipman, 1996, The Wisdom of the Bones, (New York: Alfred Knopf), p. 226-227
9. Stanley, Steven M., 1998, Children of the Ice Age, (New York: W. H. Freeman), p. 164
10. Stanley, Steven M., 1998, Children of the Ice Age, (New York: W. H. Freeman), p. 160-163