Exaptation: From Brain to Mind to Soul
Submitted to BioLogos Forum by Al Leo
Enlargement of the primate brain during the past 3 million years has no precedent in the
evolutionary history of any animal organ. Based on fossil skull sizes, Australopithecus
africanus, who lived about 3 million years BP and is considered a probable human
ancestor, had a brain capacity of 400 cc. A million years later, the brain size of Homo
hablis, who had the mental capacity to conceive of and craft useful stone tools, had
increased by 50% to 600 cc. By 300,000 yrs. BP the brain size in Homo neanderthalensis
had more than doubled to 1,400 cc. (slightly greater than a modern humans.)
Anthropologists have reasoned that the environmental pressures placed on our earliest
ancestors, mainly the rather sudden shift from the âfriendlyâ forests in Africa to drier open
savannas, made it more difficult both to obtain food and also to keep from becoming food
for the big cats and hyenas that roamed there. Certainly the enlarged brain allowed for
the thought necessary to craft stone tools that allowed the Neanderthals to become
awesome predators even though they lacked the teeth and claws of the big cats. And they
had the intelligence to âborrowâ the furs of their prey to devise clothing that kept them
warm as they moved into the game-rich areas adjacent to the northern glaciers.
Quite an accomplishment. But did that really take a 1,400 cc brain containing >80 billion
nerve cells capable of forming trillions of circuits? Was not the Neanderthal brain an
outstanding example of evolutionary âoverkillââa huge exaptation? An appropriate
analogy might be feeding operating instructions by punch card to a hypercube
supercomputer. Darwinian evolution rewards mutations that enable a life form to
survive and reproduce in the Biosphereâbut certainly not to maximize the efficiency of
any function it had accidentally produced. The hand axe is a tool invented by Homo
ergaster some 1.8 million years ago (1) that also served the Neanderthals very nicely for
about 200,000 yrs without need for significant change. The same axe design was used by
the early Homo sapiens for >50,000 yrs.âuntil their brains were, somehow, programmed
for exchanging information via language. Then tool design changed rapidly. Their entry
into the Noosphere (2) changed all the rules of âsurvivalâ. The circuits formed from the
80 billion nerve cells in their brains were somehow âprogrammedâ to retain information
that proved useful.
Brain âprogrammingâ probably did not involve adding new nerve cells. For over a
century it has been known that as the human brain matures it actually loses cellsâa sort of
âpruningâ process called apoptosis. Dawkins (3) likened this to a sculptor chipping off
bits from a block of marble to reveal the form of the figure âconcealedâ inside. Accidental
brain cell death, such as sometimes occurs during birth and can result in cerebral palsy, is
always harmful because it is random. If brain cells that serve useful circuits are
maintained while others, if unused, are slated to die (apoptosis), then mental efficiency
would be markedly improved. [âUse it or lose it.â] Glial cells constitute as much as
50% of the human brain, but, as Ben Barnes of Stanford Univ. maintains, are currently
understudied (4), but it is known that they help form and prune synapses and otherwise
actively influence brain structure and function. As illustrated by some cases of adult
hydrocephaly, the huge number of brain cells present in a human baby when it comes into
this world is not necessary to allow it to behave as a human being. It appears, rather, that
what we regard as its humanity depends on how effectively its brain cells become
âprogrammed.â
Hydrocephalus is a not-uncommon condition in newborns where an excess of
cerebrospinal fluid (CSF) causes the ventricles in the brain to become enlarged. When
sufficiently severe, a shunt is inserted to drain the fluid into the spinal cord canal and thus
relieve the pressure that may damage brain tissue. In 2007 a 44 yr. old Frenchman, who
was diagnosed with this condition as a child, was examined by physicians for a slight
weakness in his left leg. Upon taking a CT scan of his brain, they were amazed that the
ventricles were so enlarged that what remained of his brain was only a thin sheet adhering
to the skull. (See illustration) (5)
Although his I.Q. showed some impairment, he was married, had two children and had
been leading an entirely normal life. In other words, he was operating as a modern
human while having far less than half of the brain capacity of one of our ancient
ancestors, Lucy, the famed Australopithecus afarensis who lived 3 million years ago.
This certainly supports the hypothesis that the Noosphere is real, and once a human
enters it and his/her brain âprogrammedâ by it, the inefficient, chance-directed Darwinian
evolution that produced it is supplanted. Exactly how this âprogrammingâ results in
âmind/soulââin art, music, philosophy, religion & scienceâmay never become clear.
But surely we should now realize what Pierre Teilhard de Chardin maintained (2)âthat
we are creatures with one foot in the Biosphere and the other in the Noosphereâthis can
be accepted on a reasoned scientific basis, and we will never attain a satisfactory
understanding of ourselves until we acknowledge the truth of that premise.
Even if accepting the reality of the Noosphere provides a reasonable theological
explanation of how, very suddenly on the Universeâs time scale, Homo sapiens acquired
the potential to become worthy âimage bearersâ, we need to ask what implications that
has on each individual during oneâs lifetime. The intricate relationship between Spirit,
Mind and Soul still presents serious problems that will bedevil theologians for the
foreseeable future. At the moment a human egg accepts a sperm there is the potential for
a human being to be developed through an amazing process of cell division,
specialization and directed migrationâmost of the details of which are yet to be
uncovered. But if the general layout of our brains are genetically determined by
Darwinian evolution, a what point do each of us gain epigenetic access to the
Noosphereâthe âprogrammingâ that makes us truly human? Almost certainly there is no
one âpointâ of access, but it is, rather, a gradual process during which information is
assimilated from that personâs surroundings. It actually may begin before birth and
extend to the age when the child uses language effectively. Research has shown that
fetuses become familiar with the sounds of their motherâs voice as early as 18 weeks into
pregnancy, and they relate to it favorably immediately after birth. The same holds for the
kind of music the mother listens to in the later stages of pregnancy. Acquisition of
language has always considered to be the sure mark of a childâs having reached fully
human status. Legend has it that several kings have carried out experiments with
newborns, purposely raised in isolation without voice contact, to see which language was
inherent to human nature. The ancient Greek historian, Herodotus (484-415 BC), wrote
that the Egyptian pharaoh, Psammetichus, conducted such an experiment and concluded
that the childâs first sounds were more like Phrygian than Egyptian. There are numerous
fables of feral children raised by wolves (Mowgli), apes (Tarzan) or other animals, but
none of these tales offer any solid evidence of when a developing human really becomes
an occupant of both the biosphere and noosphere. Many of the stories are hoaxes, but
even when true, the children had to have had more than a year of interaction with humans
before being âraised in the wildâ. It is interesting to note that some of them who returned
to civilization after a certain critical age never were able to learn a language.
The case of Helen Keller is a little more clear cut. She contracted an illness at the age of
19 months that left her blind and deaf, but before that time she had a limited ability to
communicate with others. Perhaps, at that age, the amount of information she could share
with her parents and early companions was somewhat comparable to what the early
Homo sapiens could manage before the Great Leap Forward. The story of how Helen,
when taken in hand by Anne Sullivan for intense training, learned to live a fully active,
intellectually satisfying life was depicted in the award winning movie, âThe Miracle
Workerâ. Helenâs battle to fully participate in the Noosphere is truly the stuff of
miracles. Denied access to Helenâs brain by either sight or sound, Anne patiently used
touch to associate letters, formed by the fingers of one hand, with objects Helen could
feel and touch. The breakthrough came when Anne pumped water over Helenâs hand
while spelling out w-a-t-e-r in sign language. Once Helen grasped that the combination
of these symbols, conveyed by touch, stood for a material object, her education
proceeded at a swift pace (she graduated cum laude from Radcliffe). Almost certainly it
was the appreciation of symbols that ushered Helen into the Noosphere, just as it must
have done ages ago for the first of the modern humans.
In her book, âMan Without Wordsâ, Susan Schaller, the sign language expert, tells of a
man called Ildefonso who was completely deaf from birth but brought up in a household
with normal hearing. No one had been able to help him understand that objects had
names; i.e. symbols that stood for the real person or thing. After a great deal of trying to
teach him the rudiments of American Sign Language (ASL) she achieved a breakthrough.
She described his reaction thus: âSuddenly he sat up, straight and rigid. The whites of
his eyes expanded, as if in terror. He had entered the universe of humanity, discovered
the communion of minds, and everything had a name! This changed everything about his
perception of the world, and he became hungry for more signs, demanding more words to
expand his newly discovered domain.â In a way, he had witnessed his own birth as a
fully-human being.
The concept that the birth of symbolic humanity is closely associated with the ability to
associate names with surrounding objects, and thus is the beginning of language, is
interesting in the light of one of Godâs first actions after creating Adam, as recounted in
Gen.2: 19: âOut of the ground the Lord God formed every beast of the field and every
bird of the air, and brought them to Adam to see what he would call them. And whatever
Adam called each living creature, that was its name.â
For centuries there has been a running debate among theologians and philosophers over
the point in time that each human being is âensouledâ. Perhaps accepting the reality of
the Noosphere can do a little bit to clarify this debate. Aristotle taught that an embryo
undergoes three stages of âlife principlesâ (souls): first an inanimate âvegetableâ stage;
second, and animate or animal stage; and lastly a human stage. Others made no
distinction between types of ensoulment but thought it occurred at conception (the current
Catholic view), or at the first sign of brain activity, or when taking the first breath after
birth.
To this author at least, the most important, practical factor to keep in mind is heartfelt
respect. We can hardly be considered âhumanâ unless we respect human lifeâa life
already in existence. We also should respect, to almost the same degree, the potential
human life that has every chance to be lived to the fullest; e.g. a healthy fetus in the later
stages of pregnancy. The level of respect for a single human sperm or human ovum must
be somewhat lowerâsay the intellectual respect for the 3 billion years it took for
evolution to work out such a detailed âblueprintâ. Ideally at conception, a pair of humans
have lovingly planned to have a child, and both are thankful and respectful of the process
that they have initiated to bring that child into this world. But, regrettably, there are
many hurdles in the road ahead for any zygoteâthe first crucial one being gastrulation of
the embryo. This folding gives rise to the ectoderm, mesoderm and endoderm, and
eventually to all the organs including the brain. When invagination does not proceed
properly, spina bifida may result, but a full level of respect should still be given that
Ă„embryo/fetus since a human being is still the expected outcome. When, very rarely,
invagination goes severely awry the brain does not form at all, resulting in anencephaly.
The outcome of such a pregnancy most often results in spontaneous abortion, which
avoids the need for any moral decision. Very rarely the unfortunate fetus survives up to
the time of delivery. Question: if this were known some weeks before delivery, should
the pregnancy be respectfully terminated? Some ethical questions do not have simple
black and white answers. Modern medicine has made it possible to detect in utero a
range of less lethal defects, and the world view that recognizes the reality of the
Noosphere does nothing to ease the difficulty of making emotion-filled decisions which
must be faced in some pregnanciesâonly the realization that Creation entails both Agony
and Ecstasy, and our God has shown his willingness to accompany each of us on our
journey through lifeâs problems. Almost (but not quite) all parents with Downâs children
agree their âAngel Unawareâ gift from God has been one of lifeâs greatest blessings, but
that just goes to prove that, very slowly, humankind is earning the label âGodâs image
bearer.â
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Footnotes:
(1) âMasters of the Planet; the Search for Our Human Originsâ, Ian Tattersall, Palgrave
Macmillan, 2012; p. 124-125.
(2) Teilhard de Chardin: (a) The Phenomenon of Manâ; (b) âThe Heart of Matterâ
(3) R. Dawkins, Nature, 229 (1971) p. 118
(4) K. Yandell, The Scientist, Oct. 2015, p. 66
(5) www.medicaldaily.com
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