Thursday, June 26, 2014

#63 Skin

Before you ever came out of your mother’s womb, you had developed a fully functioning and amazing organ covering your entire body. It is called skin and it accomplishes at least 6 functions that keep you alive. Without any one of these not one of our ancestors would have survived.


Is it even possible to imagine how skin could have evolved in a slow and gradual process taking thousands of generations? If human ancestors evolved from fish with scales, then those scales had to become skin. Looking at skin for a little while in this article should convince you that scales did not turn into skin in a godless process.

The following functions of skin are all necessary for us to survive. How could they have evolved one at a time over generations?[1]

Barrier to water loss. Our skin actually keeps us from losing moisture to the air and anything that we touch such as our clothes. It also keeps nutrients in that the cells could lose if exposed.

Healing. It has amazing immunization and healing functions. It protects us from permanent damage and blood loss.

Protection against pathogens. Our skin prevents bacteria and viruses from entering our bodies. The top layer of our skin is actually dead cells which are constantly sloughing off.

Barrier to toxins and harmful chemicals. Our skin protects us from most harmful chemicals in our environment, shielding us against any damaging effects of what we touch or what touches us.

Shield and protection against damage. It is the first line of defense against injuries.

Organ for excretion of salts, urea, and toxins. Our skin actually releases a number of toxins for us. It secretes sweat to keep us cool and lubricate the skin.

Temperature regulation. Our skin helps regulate our body temperature. When we get too hot, it allows blood closer to the surface to give off heat and sweat glands release fluids to cool us through evaporation. When we get too cold, blood vessels contract to keep blood away from the surface. Muscles in the skin contract so that we shiver in order to generate heat.

Blood pressure regulation. Mechanisms in our skin increase or decrease the flow of blood in capillaries to regulate our blood pressure.

Sense of touch and pain. Everywhere on the surface of our skin we feel touch. Imagine trying to live without being able to feel anything. We are extremely sensitive to our environment, from the lightest touch of the spring breeze to the heavy thud of a hammer on our thumbnail.

Sense of hot and cold. What if you put your hand on a hot stove and couldn’t feel it? What if you took a hot shower but couldn’t tell how hot it was? What if you couldn’t tell if it was a cold day or a hot day?

Friction grip. Our skin, especially our palms and fingertips are specially designed with thicker skin and ridges so that we can grab things and hold onto them. What if your glass of milk kept slipping out of your hand?

Identification. Not only your fingerprints are unique and useful for identification, but your face is totally unique because of your skin. Take the skin off our faces and we’d all look pretty much the same.

Synthesizes Vitamin D. We all need Vitamin D to survive. Our skin makes that for us when we get enough sunlight.


I recently watched a DVD of a scientist, Dr. David Menton [2], talk for over 2 hours just about details of the skin. He hardly “scratched the surface” as they say. It was totally amazing and way beyond what I want to cover in this article. All of the above functions are very, very complicated processes involving very specialized cells in the skin. How anyone could imagine, let alone believe, that this all came about by accident is dumbfounding to me.

Let’s just talk about hair for a minute, as just one example of the complexity of different aspects in the skin. When you are born, you already have every hair follicle you will ever have. There are 3 types of hair on your body and the hair follicles are able to change themselves so that they can grow each of the different types of hair.


Lanugo hair is the type you have in the womb. It falls out before you are born.

Vellus hair is short, fine, light-colored, and barely noticeable hair that develops on most of a person's body from his/her childhood. It grows to a certain length and then stops. Eventually a totally new hair starts to grow underneath and the old hair falls out. Most of our body is covered with this type of hair as well as most animal bodies, although it is darker on animals.

  
Terminal hairs are thick, long, and dark. This is the kind that keeps growing continuously like on your head and in a man’s beard. Humans are almost the only animal that has this type of hair. Poodles are one of the very few other animals that have it.


Each hair follicle on your body has a small muscle attached to it. (Remember my Proof for God #62, Muscles, and that nobody knows how muscles could have “evolved”. [3] Well, they didn't.) So for example, if you get a chill, that muscle will make the attached hair stand up. If evolution were true, how does this make sense?

Also, each hair has a nerve connected to it that connects the hair to your brain. So when the wind blows your hair, you feel it because it registers in your brain. I’m sure you’ve noticed the wind blowing even though it is invisible. This is certainly a wonderful ability to have which makes us very sensitive to the people and the world around us.

Hair follicles have sebaceous glands [4] which secrete oils which lubricate and waterproof the skin. Specialized sebaceous glands secrete tears to help our eyes. Our hands and feet do not have these, which is a nice design feature. There are a number of different types of sebaceous glands in different areas of the body. Very, very interesting if you want to look it up.


Another amazing fact about our hair is that in some specific areas of our body there is a sweat gland which is attached to the hair follicles in that area. For example, when your body gets overheated, sweat comes out of the hair follicles in your arm pits, which helps cool you down quicker. Only one other animal sweats like humans, the horse. No evolutionist believes that we evolved from horses or that horses evolved from people, so how can they explain that we both have this amazingly complicated function in our skin. What are the odds that totally unrelated species could develop this same mechanism in their skin?


Each hair follicle is also connected to arteries and veins to supply oxygen and nourishment. Without these incredibly complex connections, we would not have hair.

Did you ever see a woman in the circus hanging by her hair and wonder why it doesn’t pull out and she falls? This is because each hair has a sheath around it which has a zigzag or ratchet pattern that is exactly matched by the surrounding hair follicle. It holds the hair in sort of like Velcro. But amazingly the hair can still grow.


OK, so I have just talked about hair so far and it's just a very small proportion of what's in your skin. But this article is getting pretty long so let me finish up quickly, but strongly note that the following, equally amazing properties of skin could all be talked about just as much as hair.

Our skin is composed of 3 layers: epidermis, dermis, and hypodermis. The very outermost layer, the epidermis, is composed of many layers of only dead cells. They are arranged in a complicated interlocking pattern like patio tiles. There are even small hook-like structures keeping them attached to each other. When a top layer of cells falls off or gets rubbed off, it gets replaced from the bottom. A layer of cells dies in the dermis and all the cells move up toward the surface. What an amazing design for replenishing the skin!


Think how amazing this is. As cells are lost on the surface, how do the cells below know to die in just the exact quantity to replace the lost cells? If your skin did not have this ability, then maybe too many dead cells would build up and clog the surface. Or maybe too few cells would be produced and all your epidermis would be rubbed off exposing the dermis where all the blood vessels and nerve endings reside.

That layer of dead cells, the epidermis, is about the thickness of Saran Wrap and yet it is totally essential to your survival. It holds in moisture so you don’t dry out. It keeps toxins and chemicals out along with bacteria and viruses.

Blood is carried into every tiny millimeter of your skin by an incredible network of capillaries. Look at this picture. There is no way this came about by random changes.


Your skin has millions of nerve endings everywhere. These are all connected to your brain and sending signals about your environment. Is it hot or cold? Are you being touched lightly or strongly? They can tell the texture of substances, whether they are soft or abrasive.

There are actually 2 types of skin. “Thick skin” is on your palms and feet. It is hairless but contains specialized nerve ending so it is much more sensitive to touch. “Thin skin” is everywhere else and contains hair.


Your palms and fingers have more specialized touch sensitive nerve endings. The name for the ending of those nerves is Meissner’s Corpuscle.[5] They are responsible for sensitivity to very light touch. How amazing that just where you need it the most, your skin provides super sensitivity. Try to imagine if your palms and fingertips were not as sensitive as they are. Read up on this type of corpuscle and how it works and tell me this is not a miracle.

You know what pain is. Do you know how miraculous it is that you can feel it? Everywhere in your skin are “specialized free nerve endings called ‘nociceptors’ or ‘pain receptors’ that only respond to tissue damage caused by intense chemical (e.g., chilli powder in the eyes), mechanical (e.g., pinching, crushing) or thermal (heat and cold) stimulation. Once stimulated, a nociceptor sends a signal along a chain of nerve fibers via the spinal cord to the brain. Nociception triggers a variety of autonomic responses and may also result in a subjective experience of pain in sentient beings. Nociceptive neurons generate trains of action potentials in response to intense stimuli, and the frequency of firing determines the intensity of the pain.” [6]

Notice that nociceptors have a special connection to the brain and even can trigger “automatic” reactions not initiated by the brain. Think about your “reflexes” and how quickly you pull your hand off of a hot stove. This is just the proverbial “tip of the iceberg” about how fantastic your skin is.

Imagine that you could not experience physical pain from your skin. You would never know if you had damaged any part of your body.

The skin on your face is what makes you look like you. We would all pretty much look alike without our skin. In fact the skin on your face has lots of embedded muscles whose sole purpose is to outwardly express your emotions. No other animals have anything like it.


All of us actually have the same color of skin. It is only because of different amounts of a chemical called melanin released in our skin that makes some skin black, brown, yellow, or red, or whatever. This too is an amazing process.


The idea that all these functions of our skin were not designed by a superior intelligence but happened accidentally over a few million years is impossible. That’s just assessing the incredible functionality of human skin. What about all the other animals that have skin as well? Some skin allows their owners to live in amazing environments, very, very cold or hot, wet or dry places. There are probably as many different types of skin as there animals. This multiplies the probability against evolution exponentially. The only thing that makes rational sense is that there must be a master intelligent designer.

There must be God.
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[1] Wikipedia, Human Skin, http://en.wikipedia.org/wiki/Human_skin

[2] Dr. David Menton, The Integumentary System (Skin), Body of Evidence DVD Series. www.answersingenesis.org  

[3] Jim Stephens, Proof for God #61, Muscles. http://101proofsforgod.blogspot.com/2014/05/61-muscles.html

[4] Wikipedia, Sebaceous Glands, http://en.wikipedia.org/wiki/Sebaceous_glands

[5] Wikipedia, Tactile Corpuscle, http://en.wikipedia.org/wiki/Tactile_corpuscle


[6] Wikipedia, Nociception, http://en.wikipedia.org/wiki/Pain_receptors

1 comment:

  1. Have you considered the topic of blood clotting Vs evolution?

    ReplyDelete