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What is Development?

We each have 23,000 genes, most of which code for proteins. Every cell in the body has a complete copy of the genetic (DNA) sequence, comprised of 3 billion letters - nucleic acids - grouped into 23 chromosomes.  In other words, genes are sequences found in chromosomes.  Genes (DNA) act as templates for the sequence of amino acids that comprise proteins. 

In front of each gene is an on-off regulatory switch, which signals whether to make more protein.  The switch is made of another protein, called a transcription factor.

If you string together a series of amino acids into a protein, they begin to fold into a characteristic 3-dimensional shape.  At that point, proteins can be used for many purposes.  As building blocks to construct the body.  As signals.  Or as catalysts, called enzymes.

Enzymes catalyze chemical reactions in the body, whereby molecular metabolites are brought together, or split apart.  The products of one reaction feed into the next reaction, in complex metabolic pathways.

Development thus proceeds, building structures in the body, sending and receiving signals (for example, hormone signals).  The receiver is usually a specialized protein, often on the surface of a cell, in which case the cell has a specific response.  In other words, if the cell doesn't have the built-in receiver (surface protein) it won't notice and respond to the signal (hormone).

The brain develops similarly.  There are too few genes (only 23,000) to specify the precise location of each of the 100+ billion neurons in the brain.  So brain development relies on construction of repeating units (there are 2 million cortical columns - processing units - each with 100,000 neurons).

I’m always most interested in the development of the brain itself, a process known as neurulation.  The neural cells continue to differentiate into specialized neurons in the brain.  A sort of chemical grid, or map, guides them as they migrate to their proper position, connecting with other neurons along the way.

There are two types of development in the early brain.  Activity-independent mechanisms (such as differentiation, migration and axon guidance) proceed according to genetic programming, independent of the environment (neural activity and sensory experience).

But once the neurons are in place, with their axons connected to other neurons, activity-dependent mechanisms of development (influenced by the environment) can begin.  Neurons do not connect directly with each other.  Instead, there is a gap, called a synapse, between every neuron, where chemical signals pass back and forth.  The chemical signals are vulnerable to being intercepted by drugs, like antidepressants and antipsychotics, because the brain is designed for exploitation by "global signals" and external agents (if not, the neurons would connect together directly).

The synaptic connections between neurons change over time, influenced by our experiences. But those are not just any experiences.  They are the specific experiences for which our development was programmed to respond, like an elevator which is programmed to respond to "button presses" but not loud screams.  Some genes are programmed to switch off (semi-permanently) in some people under certain environments, which is why identical twins (people with the same genes) may differ.  One twin may have a slightly different experience in his life, for which a particular gene is programmed to switch off, so now the twins have, in effect, different (active) genes!

We learn skills, perfect them, and make new memories – all of which are possible by the activity of the brain.  The genetically developed substructures in our brain help us remember new things (hippocampus), motivate us (amygdala), allow us to plan (frontal lobes), and learn language and other skills.  Evolutionary psychologists believe we have evolved hundreds of specialized regions in the brain, each triggering specialized human desires, motivations and behaviors.  Since each of us has different gene variants (probably leading to a different amygdala structure), no two people are motivated by the same things.

Key points

Genes develop the body and brain.  But the body has some of the properties of a mechanism, like a toaster.  It has an internal state (a toaster has on-off states).  It's behavior depends on environmental stimulus (a toaster needs someone to press the lever).  Genetic development is unlike a toaster, in that it assumes input from the environment for tuning purposes.

Saying "genes cause human behavior" must consider this developmental intermediary.  Genes are blueprints for development, and the resulting body/brain are what cause the behavior.  It's somewhat indirect.  But that doesn't make behavior any less innate.

The Necessity of Death?

It's often said that great mathematicians do their best work before turning 30 years old.  Even Einstein, the great physicist, said the mind is crippled after 40.  At that time, he gave up his rebellious, bohemian ways, and joined the respectable, settled bourgeoisie.  He defended his earlier theories against competing theories for the rest of his life, even as his creative streak eased with age and fame.  "Glittering reknown is still draped around the calcified shell," he said.

Once people get older, they morph into the authority figures they formerly rebelled against, defending their turf with remarkably little irony.  1600 years earlier, after muttering "Grant me chastity and continence, but not yet", St. Augustine finally gave up his mistress in his 30's, and pledged himself to celibacy, then admonished others who followed his own (earlier) path to enlightenment.

The point is, many young people are foolish, rebellious, highly creative, and willing to challenge authority.  That's good for the survival of society and our species.  But when older, we become the authorities, and we don't like to be challenged.  Our brains become more ossified, calcified, and settled in old ways.

So what do you do with 30-something mathematicians?  To keep a steady stream of creativity, Nature long ago introduced the concept of death (by so-called "natural causes"), to power the steady cycle of natural selection. To allow society to evolve and remain well adapted to changing times, it was considered easier (by Mother Nature) to kill the recidivist individual (or, rather, skimp on proper bodily maintenance) instead of re-plasticizing him to take on a new form.  You only get one puberty and early adulthood.

You might say immortality would be pointless for someone like Einstein, because many people would continue to defer to his status and fame, even as his creativity declined.  Therefore nothing new would ever be invented, and society would decline.  But death is bad, right?  Especially by holocausts brought on by perverted governments, but also death by natural causes.  Most people passively accept this fate.  But I certainly don't want to die.

Can't we figure out a way to re-plastize our brains (like a second puberty), so the draconian death concept can be retired?  I don't want to be a "calcified shell" spouting the same ideas 30 years hence.

Development

Human development is breathtaking in its complexity.  After an egg is fertilized by a sperm, the cell starts to divide.  Some of the earliest cells in the clump are known as embryonic stem cells because they can duplicate themselves endlessly, and change themselves (or differentiate) into any cell in the body by selectively switching off some of their genes.

Later, the cells become more specialized.  The neural stem cells can only differentiate into neural cells of various kinds, and skin stem cells can only differentiate into skin cells (but not neural cells), even though the underlying genes in each cell are still the same (but selectively de-activated).

As development continues, three layers of cells (germ layers) form – the “ectoderm”, “mesoderm” and “endoderm”.  The mesoderm cells further develop into the muscles and blood, the endoderm develops into the digestive tract and lungs, and the ectoderm develops into the skin, nerves and brain.

It's all an iterative process of increasing cell specialization.  As our hands develop, for example, they begin as tiny buds of mostly undifferentiated cells, like the hands of gingerbread men.  Initially, our fingers are webbed like frog feet, but eventually the webbing cells are killed when they receive the programmed cell death signal, for which they are designed to respond.

I’m always most interested in the development of the brain itself, a process known as neurulation.  The neural cells continue to differentiate into specialized neurons in the brain.  A sort of chemical grid, or map, guides them as they migrate to their proper position, connecting with other neurons along the way.

There are two types of development in the early brain.  Activity-independent mechanisms (such as differentiation, migration and axon guidance) proceed according to genetic programming, independent of the environment (neural activity and sensory experience).

But once the neurons are in place, with their axons connected to other neurons, activity-dependent mechanisms of development (influenced by the environment) can begin.  Neurons do not connect directly with each other.  Instead, there is a gap, called a synapse, between every neuron, where chemical signals pass back and forth.  The chemical signals are vulnerable to being intercepted by drugs, like antidepressants and antipsychotics, because the brain is designed for exploitation by "global signals" and external agents (if not, the neurons would connect together directly).

The synaptic connections between neurons change over time, influenced by our experiences. But those are not just any experiences.  They are the specific experiences for which our development was programmed to respond, like an elevator which is programmed to respond to "button presses" but not loud screams.  Some genes are programmed to switch off (semi-permanently) in some people under certain environments, which is why identical twins (people with the same genes) may differ.  One twin may have a slightly different experience in his life, for which a particular gene is programmed to switch off, so now the twins have, in effect, different (active) genes!

We learn skills, perfect them, and make new memories – all of which are possible by the activity of the brain.  The genetically developed substructures in our brain help us remember new things (hippocampus), motivate us (amygdala), allow us to plan (frontal lobes), and learn language and other skills.  Evolutionary psychologists believe we have evolved hundreds of specialized regions in the brain, each triggering specialized human desires, motivations and behaviors.  Since each of us has different gene variants (probably leading to a different amygdala structure), no two people are motivated by the same things.

What is Expectation?

Expectation is an assumption built into one's form.  Such assumptions are made during the process of an organism's development, as well as in the organism's present decision-making.

What does it mean to have an assumption built into your form?  During evolution, organisms always existed in a certain place and time, with a given environment.  As organisms evolved (in that place and time) in response to changes in their environment, certain aspects of the environment became the assumption behind the new form.

For example, frogs evolved to detect fuzzy dots in the sky and to leap toward them with their mouths open.  The expectation (built into the frog's form) is that fuzzy dots are flies for a meal.  In this sense, expectation is another way of saying "circumstances from long ago that are assumed to have remained constant" and thus are implicit in the frog's design.  (Also, note that "design" only becomes apparent in a specific environment -- if fuzzy dots are not flies, the frog will soon die).

Present-day decision-making also involves expectation.  A general may command his army to dig trenches or prepare artillery positions and wait for his next command.  Once these are in place, the general can expect that his simple order canl be detected by the prepared troops (verbally, or electronically, or visually), and once received, that signal will trigger a great battle. 

Compare this to hormone receptors, which (like a general preparing for battle) are strategically placed throughout the body to await a signal (a few drops of hormone), for which they already know how to respond.  Once that hormone is released into the bloodstream (like a general's order), those receptors detect the signal and enact their scripted response.

What was the State of Nature?

The State of Nature is a device used by political scientists to describe the state of mankind before civilisation and governments were established. John Locke, for example, described the State of Nature as an essentially peaceful time with abundant resources. Thomas Hobbes, on the other hand, declared it a time of war of "every man against every man" in which life was "solitary, poor, nasty, brutish and short."

Locke and Hobbes had different notions as to why establishing a central government was important: Locke wanted government to ensure individual rights to "life, liberty and property" whereas Hobbes preferred a central authority to keep men in awe, so they would honour their contracts and commitments.

But my use of the term "State of Nature" does not refer to governments. Instead, it describes the period of time 1.8 million to 10,000 years ago (the so-called Pleistocene era) when man finally evolved from apes and proto-humans.

The State of Nature was not a single moment or generation, however, but a duration of many thousands of years. Mankind evolved in a changing environment, and so we have different scenarios manifest in our genes for each of those times. During the ice ages, we evolved a body type and mental disposition for that environment. During times of prolonged war and upheaval, we evolved traits for those times. During times of peace, we evolved for that as well.

Evolution is a process by which an organism's genetic qualities are continually matched against the environment. Those who survive, especially those with advantageous genetic mutations (which occur from time to time) are deemed most fit in the environment. They are able to have the most offspring and promote their family line.

As a society, we are constantly repeating the different States of Nature. Our ancestors killed nearly all of the Indians, and relished doing it. We now repudiate our ancestors, and cannot imagine why they were so brutal. But in truth, we are the same people, simply in a different State of Nature. The States of Nature roll over us, working like a periodic engine of change.

Individuals don't evolve by themselves. Society does, as a collective beast. Society has evolved many different stable distributions of traits across people for the various scenarios from the State of Nature. Different people serve different roles. Some are born as leaders, as shown by their desire to lead a hierarchy of men, without being cowed by the disapproving glances of rivals. Some become labourers, because they desire approval from great leaders, and are not motivated to compete for power.

But mankind retains in its collective genome the different possible societal configurations from the State of Nature. A stable social state, with its tuned distribution of traits, can return quickly if the ambient environment so warrants.

Tuning & Expectation

When we are born, our eyes are not fully developed.  We need to see the world in order to "fine-tune" our vision.  We need to be exposed to horizontal lines, vertical lines, various shapes...   Babies have a natural instinct to keenly observe the pattern in front of them when they are being held, and that pattern is nearly always a face!

Once the genes tune a part of the brain to recognize faces, the genes can then build other circuitry that depends on it... such as being cowed by a frown pattern, or being excited by a smile pattern.

So the genes don't have to specify everything in our mind, for those things to be innate.  The genes can make certain assumptions about the environment, like a plant can make assumptions about its environment (the sun will rise, wiggling will usually help it get around obstacles, it will rain occasionally).  Anything that's reasonable to expect in the environment is reasonable to be left out of the genes.

A young child who has one eye (but not both) closed for an extended period will have permanent problems with their vision.  But it's reasonable to expect that this situation will not usually occur.

Someone with innate leadership ability simply has a cluster of motivations and emotions.  They need to be tuned, in order for that person to be an affective leader.  They are the basic building blocks for leadership.  Some people don't have those basic building blocks, and so will not desire to become a leader ("I chose not to be a leader of my own free will," they may say) or will not have the ability to become a leader.

In order to develop leaders, first you need to assemble a group of people with the leadership genes.  You don't develop leader's basic motivations and emotions... you tune the people who are already leaders.

Expectation, or How specific must our genes be?

A frog, whose behavior is mostly genetically determined, simply has to leap into the air with its mouth open when it detects a small blurry dot passing by. It does not need to know about flies, nor does it need to worry about eating. If a fly ends up in its mouth after the leap, a different reflex can be triggered, and the frog eats. The frog does not need to relate one event with the other. Because the environment is set up the way it is, small blurry dots are usually flies, and the leap usually leads to a mouthful of food, which triggers the response to eat.  The frog's instincts don't need to be more specific, as long as certain expectations about the environment remain true.