PRIMATES &
HUMAN EVOLUTION
SKIN
The supple and resistant dermis is much thicker than the epidermis.
Its water content is over 60%.
It is made of dense fibrous connective tissue, primarily collagen. Another fiber is elastin, your head has more of it.
Together they give your skin its super elasticity.
The dermis can repair itself and renew injured tissue.
This chapter is divided into two sections:
While grooming my skin, I was faced with experiences that contradicted traditional dermis theory.
It is a shame that all our knowledge about skin has been gathered by people who haven't had the courage put their nails on it.
So, most of it is wrong.
Dermatologists know nothing about skin.
One of the first observations you make when you groom is that your skin is obviously folded.
Not just a few folds here and there, but a generalized folding of the dermis.
Thousands and thousands of folds that you can feel with your fingertips and nails, while your eyes can only discern a few.
While the origin of some folds is clear, because they are liked to actions you make or positions you take, you will discover a grid of vertical and horizontal folds all over your body.
Folded skin, and how to unfold it, is the basis of grooming.
Yet, dermatologists don't actually believe that the skin is folded.
They call the folds "Langer's lines".
As you can see, the folds in the skin had been noticed, long ago, by forensic pathologists, embalmers, butchers, ...
In 1861, Austrian anatomist Karl Langer drew the following chart of what he called «lines» in the skin.
Langer described his lines as deep bundles of collagen inside the skin.
Surgeons try to cut on them, (when they can see them), in order to obscure the incisions they make.
For more information on skin folds, see the following pages:
How could skin specialists not understand that the skin is folded?
Just looking at a fold you can see that the tissue is bent over.
The fact that they are folds changes everything; because folds can be unfolded.
Understanding this also makes you consider that folded skin may be unhealthy and that the performance of its components may be greatly affected by the folding.
Worse, a lack of comprehension about folds is a lack of comprehension about pain.
The dermis is packed with free nerve ending and specialized pain receptors (nociceptors) and the folds sure fire them into action.
There are many existing maps showing Langer's lines on the body.
They resemble my horizontal and vertical folds illustrations.
I'm sorry to say that these maps are very wrong.
They don't even show the vertical center fold that divides your body into two halves.
You can see some horizontal or vertical folds, but never in the same place.
The reality is much more complex; you have a matrix of vertical and horizontal folds on which you add location folds, posture folds, action folds, expression folds, ...
The maps above are based on visual inspection, while mine are the result of feeling the folds with my fingertips and nails.
They are not lines, but folds.
Sebum glands were designed with grooming in mind.
There are about six times more of them on your head, where you are more folded and where more grooming is needed.
Known as «sebaceous glands», they are attached to the top of the hair follicle shaft.
Humans don't know why they have sebum glands.
They are annoyed when these useless glands expel large quantities of sebum or worse, when they get blocked and form pimples.
Dermatologists talk about overactive sebum glands and their excessive production, possibly due to some hormonal imbalance.
In fact, their content is supposed to be expelled regularly when you groom your skin.
Now, grooming and fold theory give us another picture of what is actually happening in your skin.
Sebum, an oily, waxy substance that is unique to mammals.
It lubricates the skin while you groom.
It enables your nails to glide over the surface without tearing it.
Regular grooming frees the glands from their content.
Failure to do so has resulted, in our race, in huge glands compared to chimpanzees.
It also keeps hair and fur shiny, flexible, impermeable, ...
Here's how it works.
Sebum, a natural lubricant, is released when your nail inclines the hair shafts while raking the shin.
•As your fingertip and nail pass over your skin, they bend the base of the hair they encounter.
•This creates a mechanical pressure on the sebaceous glands to release some of the sebum.
Hair varies in size all over your body.
To equalize their lubricating effect, sebum glands are;
•Big on smaller hair (neck) and
•Small on bigger hair (beard).
My grooming experience shows that most problematic sebum build-ups are not in the glands themselves, but are the result of having several glands expelling their content inside a fold or a fold crossing, where the sebum accumulates.
Folds and fold crossings are much larger containers and can accommodate the large quantities of sebum we sometimes see.
No tiny sebum gland could hold that much.
Your lips, eyelids, penis, labia minora and nipples are hairless, but they still have sebum glands. It reaches the surface through ducts.
Since your palms and soles have none, their skin is special. It is thicker and easily groomable. You can even see the folds there.
On a human fetus, these same sebum glands secrete the white substance called Vernix caseosa.
• Skin pores
Pores are very hard to see when they reach the surface of your skin.
When you think you can distinguish them individually, you are in fact probably looking at fold crossings.
They may be very close to one another and follow orderly patterns, but this simply confirms the presence of folds beneath them.
The top of the dermis is undulated, mostly on your palms and soles.
On the tip of your fingers, these ridges are commonly known as fingerprints.
When you look at your fingertips, you can see their design as nice rounded curves.
You can also spot many irregularities, with lines and holes modifying the motif.
Those alterations are caused by the presence of folds in the skin of the fingertip.
I believe that the basic fingertip pattern should follow straight horizontal lines, though slightly rounded because the finger is round.
Their horizontal direction is designed to prevent slipping while grasping branches.
Any swerves, curb and loops are due to folds in the skin and the crossings they create.
You can see several of the bigger folds when your hands are wet.
Skin is an organic tissue.
My suggestion is that the orientation of the skin’s various elements; cells, fibers, ..., follows a general horizontal-vertical axis.
We all are familiar with woven materials which exhibit a similar foundation.
We can also see it in our food.
This orientation favors straight, on-axis folding of the skin.
Your skin of the top of your head is so folded that you call it "scalp".
This dense folding puts so much pressure on the hair follicles that their performance diminishes throughout one's life.
This causes whitening and thinning of the hair cover, but can lead to baldness.
The «arrector pili» muscles actually pull your hair out of your skin.
This creates elevations called «goose bumps».
Under the control of the autonomic nervous system, they react to fear, cold, excitement, ...
Shivering is caused by these muscles contracting and relaxing cyclically, generating heat.
Unfortunately, the skin on your head is so folded that the muscles do not function.
Your hair should stand stiff on your head when you are emotionally charged, the way it does for some groomed primates.
An area of your skin may contain various amounts of the following constituents. Some are found only in specific locations.
The dermis is laced with tiny blood vessels.
Capillaries find their way up into the epidermis.
Bundles of nerves reach up into the epidermis.
These neurons communicate bilaterally with your brain, but also do so between each other, thus creating a neuronal grid all over your body.
Free nerve endings are responsible for detecting temperature, mechanical stimuli (such as pressure), pain, and touch information.
Hair is a compressed, filamentous creation of the skin found only in mammals.
Each hair follicle has:
•Blood vessels feeding it,
•Nerve endings (each one can feel),
•A muscle,
•One or more sebum glands,
•...
The hair is supposed to be loose at the top of the follicle.
If so, the sebum can escape through the free space around the hair in the hair shaft.
Even though humans are labeled as hairless apes, they have more hair follicles per square inch of skin than other great apes such as chimpanzees and gorillas.
You will find them everywhere on your body except on your palms, soles, lips, eyelids, penis, labia minora and nipples.
Called eccrine glands, most are part of your thermo-regulating system.
Sweat, almost all water, is cooled by your movements while it evaporates, thus reducing your internal temperature.
Some sweat glands are different. Those on your forehead, underarms, palm and soles respond to psychological stress.
Some areas of your body also contain specialized nervous receptors.
They complement the information from the free nerve endings through tiny corpuscles.
What each one does precisely is still debated, but some seem to react more to specific types of stimulation such as heat, pressure, ...
There is an astonishing concentration of such receptors on your fingertips, making them the most sensitive part of you.
SKIN
This is a layer of fat between your skin and whatever lies beneath it, muscle, bone, organ, cartilage, gland, ...
The hypodermis is not necessarily considered as being part of the skin.
Your body uses it for insulation and as an energy reserve.
Blood vessels and nerves travel through it to reach into the skin.
SKIN CARE
BEAUTY
HUMAN EVOLUTION
PRIMATES