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Our Largest Organ: an amazing and diligent assembly

vcruz's picture

Our skin, that susceptible boundary that wraps around our organisms deserves much more thought and appreciation than we usually give to it. The skin also deserves more understanding of it, aside from its color and texture; we should understand the complexity of its nature. Once we do this we will be amazed and value more our skin. This is what Nina Jablonski intends in her book Skin, a natural history. In her book, Jablonski starts exploring the ways in which our skin has evolved throughout times and then delves in the complexities of it, such as the history and reasons behind our skin color, and the ways in which our skin reacts to our emotions. What I want to share in this essay, is a small but amazing account of what the largest organ in our body, our sensitive skin can do not just to protect us, but also to react in conjunction with our emotions and desires. Also, I want to share some of the social aspects that are involved in the need of understanding our skin.

As Jablonski describes it, “the skin is the flexible, continuous covering of the body that safeguards our internal organs from the external environment” (Jablonski, 1). As sensitive as it is, the skin protects our internal organs from any physical, chemical, and microbial agents. Our skin works day and night, even though we don’t even think about it, selectively leaving some things in and some out. It also works hard to regulate our body temperature. Among the many components of our skin, we also have a very important group of nerves, the sympathetic nerve fibers, which belong to the nervous system and are responsible for “fight or flight” reaction when there’s a possible threat to the system (Jablonski, 112).This amazing organ, with the help of the sympathetic nerves, also helps us stay connected with our surroundings.

Among the many important tasks that the skin is responsible for, there are many things that we don’t know or think much about. One of this tasks is its protection from the sun as a cause of the formation of our skin color, which, if ignored can affect our social perceptions. For instance, ignoring the origins of the skin creates misconceptions about what our skin reveals about us as individuals.  Even though our skin can reflect our age, heritage, state of health, and cultural identity, it can’t establish who we, as a person, are or how our children will be. The unfortunate racial differences, mainly based on skin color, can sometimes separate individuals; therefore creating default descriptions of each group and consequently of each person. However, our skin color is only one more of our biological differences, and should not make any social difference.

Jablonski explains that the different shades of our skins exist by the amount of melanin pigment in our bodies, which evolved “by evolution through natural selection” (Jablonski 65 - 75). In the natural selection process, our skin needed to be dark enough to “prevent or slow the breakdown of important biomolecules in the skin by UVR” or light enough to “permit the production of the important biomolecules catalyzed by UVR” (Jablonski, 80). There were two evolution gradients of skin pigmentation – photoprotection and vitamin D production – which caused light pigmented skin to be near the poles and darker skin near the equator. Thus, the skin color evolved to protect our bodies in the different regions that we lived in.

        As mentioned earlier, another of the wonderful tasks of the skin is to keep us connected with our surroundings. It is because of our skin that we can feel a gentle touch, or a refreshing breeze. But there is another way in which our skin keeps us connected with our surroundings, that is by showing our emotions. Our skin also expresses how we feel in visible ways. For instance when we are embarrassed or angry, we turn red, particularly in our face. Turning red in the face happens when our heart rate and pressure rise, our peripheral arteries compress, and there is an increase in blood flow to our face (Jablonski, 115). Facial reddening is experienced by all humans regardless of skin color, however, the level of reddening is not the same and not as noticeable in all skin colors.

                Besides embarrassment and anger, our skin also expresses our fear. When we are afraid, the sympathetic nerves in our skin respond dramatically contracting the small arteries in the dermis, activating the sweat glands, and stimulating the minuscule muscles in our hair follicles; all of this results in “pale, clammy skin, hair standing on end, goosebumps” (Jablonski, 113). Yet, for all of this to happen, one needs to be very scared, so that such a response from our body.

                The sweatiness that we experience when we are scared also happens when we are anxious. The sweatiness that we experience when we are nervous or anxious is referred to as emotional sweatiness to distinguish it from the thermal sweating that helps to maintain our body cool. This emotional sweatiness is experienced in the eccrine sweat glands in the palms and soles. Emotional sweatiness reveals the mood of the nervous system even at its slightest level. This was very advantageous for scientists on their studies and inventions as well as for law enforcement authorities who, with the aid of the lie detector, were able to determine whether a person suspected of a crime was lying.

                Finally, Jablonski also considers the skin to be “the largest sexual organ of the human body”, she explains that, “much of the pleasure of sexual intimacy comes from the exquisite expectation of touch and the delight and relief of skin-to-skin contact with another person, before, during, and after the sex act itself” (Jablonski, 119-120­). Our skin also reacts when we talk or even think about sex, and these reactions are in accordance with our social upbringing. Jablonski provides the example of people who become uncomfortable and blush when talking about sex because they have been raised in a culture where sex is a “sensitive or taboo subject” (Jablonski, 120).

                Nina Jablonski’s book helped me, in many ways, to understand and appreciate more the complexity of the skin. I have always thought of skin color as a beautiful array of shades in humans that only adds to our diversity, and I have found it annoying to think of it as a social classification. The explanations that Skin has about skin colors confirmed my beliefs and the absurdness of trying to categorize humans, and their personal entity, by skin color. Another aspect of the human skin that amazes me is its incessant work to protect our internal organs. And finally, the incredible ways in which our skin connects us to our surroundings are one more reason that should make us take care of and value such an imperative and hard-working organ.