Monday, June 18, 2012


Adolescence never ends.  There’s no physical marker for the end.   The beginning is quite clear, because it is a mammal phenomenon, driven by the maturation of the creature.  Right now across Montana there are adolescent grizzlies coming out onto the prairie, often in sib-pairs, following the streams as highways, using the brush the streams support as bedrooms and hideouts in the day time between raIds on farms and ranches.  Bears, like many predators, are diurnal -- up and traveling in the morning and evening.  Napping in the afternoons and wee small dark hours.  Unless there’s a bright moon.  Are humans so different?  
The cougars have been moving out of the back country for decades, sometimes mistaking the highways for rivers.  They are not likely to be in pairs.  Bears like birdseed and apple trees.  Cougars prefer small dogs.  Growing animals need lots of food and sleep.  At the point when sexuality is coming online in mammals, the results are disconcerting to the creature and others.  It’s not a steady climb, but a jerky business of stinks and starts, wants and hates, strange dreams in unknown territories.  
Humans are not different.  Adolescence is one time that our mammal natures are obvious and sometimes controlling everything else.  We used to keep baby animals for pets -- very politically incorrect and ecologically unsound, but it was a long time ago and sleeping with baby foxes and bobcats is even more seductive than cuddling kittens and puppies.  Their preparation for adulthood ended in the fall and since we didn’t confine them, it was a matter of distancing from us to find their own territory.  First missing for part of the day, then overnight, then rarely coming back -- a little gaunt and tattered in order to eat and sleep for a day or two (and leave tracks in whatever newly poured cement there was) -- then gone.   
A too-high percentage would never been seen again because they were killed, often by males of their own kind.  Probably higher than normal death rates for our pets because they didn’t learn what animal parents would have taught them.  Do you remember how Elsa the lion struggled to learn from her human surrogates how to be a lion?
Death is one way to end adolescence, even for humans.  More and more of human adolescents are dying now because no one taught them how to be in the world.  Even adults who were conscientious and taught what they know cannot provide advice on some of today’s impossible situations.  No wonder the bitter struggle to keep the world the way it was when the parents were learning their own way.   
But all of the above is wrong because I’m confusing adolescence with puberty.  Adolescence is a culturally constructed state.  Puberty is physical.
In fact, there IS no end of adolescence in a biological sense.  That’s because when we talk about animals, we’re really talking about puberty.  Adolescence is a human cultural and psychological complexification of puberty, which is the result of a development in the adrenals that produces a molecule sequence resulting in sexual maturity.  What follows is biological info from Wikipedia.  (Scientific matters are generally reliable there.  Generally.)  Skip it if you want to, but I find it fascinating, maybe because I personally had a tougher time with “adrenarche” than with puberty.  Primary school was for me a time full of aching, bad dreams, temper tantrums, tears and raw terror.  For a while I’ve been searching for more info on this stage, but there’s not much about it.  Children’s books are often focused on this age, which is when many people learn to read and alternate realities spring to life.  (“Winnie the Pooh,”  “Alice in Wonderland,” “The Little Prince”)

Adrenarche is an early sexual maturation stage in some higher primates that in humans typically occurs at around 6 to 8 years of age. During adrenarche the adrenal cortex secretes increased levels of androgens such as DHEA and DHEAS, but without increased cortisol levels. Adrenarche is the result of the development of a new zone of the adrenal cortex, the zona reticularis.  Adrenarche is a process related to puberty, but distinct from hypothalamic-pituitary-gonadal maturation and function.  Adrenarche occurs in only a small number of primates, and only chimpanzees and gorillas show a pattern of adrenarche development similar to humans.
The zona reticularis is the innermost layer of the adrenal cortex, lying deep to the zona fasciculata and superficial to the adrenal medulla. The cells are arranged cords that project in different directions giving a net-like appearance (L. reticulum - net).  Cells in the zona reticularis produce precursor androgens including dehydroepiandrosterone (DHEA) and androstenedione from cholesterol.
DHEA is the most major steroid in the body and seems to have something to do with fertility, glucose metabolism and the operation of neurons.  It’s a precursor and intermediary for a LOT of processes, possibly contributing to longevity.  In Canada one needs a prescription but in the US it’s a “health food supplement.”   If athletes take it, it is considered “doping”.  If housewives take it, it is considered a “pick me up.”  It’s very popular but there’s little testing done.  The decline of DHEA begins at thirty, after maturation in humans is complete.  Perhaps that is the biochemical end of puberty.  Once it was about as long as people lived, barely long enough to raise a child who could survive without a parent.
Doctor Hal Bieler, author of “Food is Your Best Medicine,” was often around here in the Sixties.  He had a great fondness for John Clarke, the Blackfeet woodcarver,  and he liked to make little bear figurines that he sold.  He was also generous with his opinions and intrusions.  He used to say that Bob Scriver was an “adrenal” type.  (His tripartite sorting system was based on the dominance of one of three organs: the adrenals, the pituitary, or the thyroid.  He only applied it to men.  He wasn’t very interested in women.)  It would be interesting to know whether that traced back to DHEA from the Zona Reticularis:  high energy, aggression, strong sexuality, and hairiness.  Bob was always teased about being a “bear.”  We associate puberty with sexual maturity but the marker is the secondary sex characteristic of axillary hair, which today some spend a lot of time, money and pain removing.
Puberty is actually the result of the adrenarche, the precursor for the better known male and female hormones of sexual function.  Are the years of six to eight or nine far more crucial than we’ve thought?  My family used to drive long distances and my father liked it best at night when we kids slept in the back instead of quarreling.  Except that I tried not to sleep because the adult conversation was pretty interesting.  I was in late adrenarche when they had a discussion about puberty.  My father thought it was a dirty word because he confused it with pubis, an anatomical feature cushioning the genitals in front.  I think our whole culture has gotten human sexuality confused because of embarrassment and lack of accurate definitions.  Taking DHEA will probably not help this.  Why is it that bears don’t have an adrenarche or even a zona reticularis?  There is no end to questions.

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