יום רביעי, 6 ביולי 2011

Inappropriate table conversation #1 – The evolution of the clitoris and the female orgasm

I would like to address a question that had flabbergasted many good men including yours truly. Before I begin, I want you to consider the following statements, after cross-verification of a few sources[1,2,3]:

  • Approximately 50% of women seldom or never experience an orgasm during sexual intercourse.
  • Over 90% of women reach an orgasm by clitoral stimulation.

Of course, whether we admit it or not, we know it for a fact that sending our female partner raging towards a climax requires a considerable degree of finesse. This problem arises for various reasons, but the most interesting one is the physiological location of the clitoris. Firstly, in case any of the people reading this are… how shall I put this?... ‘sexually challenged’, let me begin with a simple and concise description of the female genitalia[4]:

(Click the image to enlarge it)

The glans clitoris is better known just as clitoris, it contains a very high concentration of nerve endings, making it extremely sensitive and well-suited to sexual stimulation [5]. It is covered by a protective fold of skin called prepuce of clitoris. As you have probably already noticed, the vaginal orifice (yes, my friend, this is where you most preferably get in) is located in a considerable distance from the clitoris itself.

This description is in obvious accordance with the wide-spread difficulty to reach an orgasm by sexual intercourse. So, finally reaching to the burning question: Why, in the name of all that is fair in this world, did the clitoris come to be in this horrific location?

Quite understandably, this subject had been under both scrutiny and debate by the evolutionary society and many possible explanations had arisen. I have to tell you – these suggestions, as innovative and unfeigned as may be, might leave you utterly flummoxed, staring at the screen and scratching your head.

Since I don’t want to make this post overly protracted and odious, I will shortly view only 3. The rest, I will leave in your trusty hands and critically thinking minds:

Explanation #1 – 2 Girls 1 Orgasm
(Scientifically: Natural Selection of Social Mechanisms)[6]

It is suggested that the location of the clitoris can be explained by watching the Bonobo apes[7]:

(Click the image to enlarge it)

They live in a matriarchal society (which basically means that the women are those wearing the pants). The Bonobos are completely bisexual – about 50% of their sexual acts are with members of the same sex. And boy, do they have a lot of it! They go at it once every 2 hours and even twice as often if the relationship is considered newly established. Oh, and Bonobos are one of the few mammals that have heterosexual sex face-to-face, romantic huh?

The cool thing about their society is what sex means to them. Bonobos use sex to relieve aggressive tensions and, believe it or not, to solve conflicts. If a controversy is presents, both sides will often have sex with each other to lower aggression before approaching the problem. Imagine how our courts of law would look like if we used the same method... eek!

And the position of the clitoris? Well, since males had been under strong selective pressures to develop orgasms as incentives for reproduction, they have swiftly adapted with sufficient motivation for both females and males. The position of the clitoris, according to a famous study[8], is on the front because this location “promotes same-sex mating and may yield more effective same-sex bonds, increasing overall Darwinian fitness at no reproductive cost”.

Touché, lesbian sex… touché.

Explanation #2 – Hey! Dimwit! I’m horny!
(Scientifically: Sexual Selection of Inter-species Signaling)

Here we learn about the location of the clitoris from the Spider monkeys (Not to be confused with spiderpig)[9]!

(Click the image to enlarge it)

More specifically, they are called "Geoffroy's spider monkey". These monkeys form fission-fusion societies, which means they have a large general society that divides into small closed groups during different times of the day.

In contrast to the Bonobos, they usually have sex in a sitting position while the male hugs the female from behind[10,11]. And this is interesting: the sex itself takes between 8-22 minutes, but prior to the act they both separate themselves from the rest of the group[12]. That's right boys and girls - they need privacy.

And the position of the clitoris? It is suggested that the clitoris is located on the front for communication purposes. During sexual arousal, blood pumps into the clitoris, causing it to slightly redden and swell and under some circumstances to release olfactory cues (chemicals with smell). All of those make the female conspicuous to other males.

Explanation #3 – Chance fucked me over
(Scientifically: Neutral Evolution by Embryological Constraints)

In a study which received a great deal of media attention (The New York Times, The Manchester Guardian, Lancet, Nature, New Scientist, Slate and more), it was suggested that the position is not an adaptation at all! Instead, the study claims it to be a developmental 'byproduct', or as evolutionary biologists call it 'Homology'[1].

This basically means that the position of the clitoris is not functional or beneficial in anyway. How is that? Both the male and the female reproductive systems are derived from the same basic, "asexual", origin called Genital tubercle. This is how it looks like in a 10 weeks old fetus[4]:

(Click the image to enlarge it)

Looks pretty much the same right? Just as we expect it to be! As we said, they both have the same origin. After the full maturation, we can see the strong developmental relation between the systems. The complementary structures are presented in the same color[4]:

(Click the image to enlarge it)


In summary: there are many (interesting) explanations for the physiological location of the clitoris. Many of them are still in debate. Either way, we men must stay the course and take on the mission to escort our lovely partners to the peak.



References
  1. The Case of Emale Orgasm: Bias in the science of Evolution, Elisabeth A. Lloyd 2005. Cambridge: Harvard University Press. ISBN 0-674-01706-4.
  2. Sex study on Female orgasms, "Rule of Thumb", ABC News Health Desk 2009.
  3. "Dissatisfied, ladies? Tips to reach the Big O Climax is possible for every woman, and men can help them get there!". MSNBC. November, 02, 2007. Retrieved April 10, 2011.
  4. Netter Atlas of Human Anatomy, Frank H. Netter, M.D. 2003, Icon Learning Systems. No violation of copyright intended, I will gladly remove this content to the author's request.
  5. Handbook of Psychophysiology By John T. Cacioppo, Louis G. Tassinary, Gary G. Berntson Contributor John T. Cacioppo, Louis G. Tassinary, Gary G. Berntson Edition: 3, illustrated, revised Published by Cambridge University Press, 2007 ISBN 0521844711, 9780521844710 898 pages pp 246-247.
  6. Girl-On-Girl Bonobo Action And The Location Of The Human Clitoris, The Preston Grant 2011.
  7. Photo by Ltshears via Wikimedia Commons.
  8. Evolution's Rainbow, Joan Roughgarden, Stanford faculty of Life Sciences 2004.
  9. Photo by Steven G. Johnson via Wikimedia Commons.
  10. Rowe, N. (1996). The Pictorial Guide to the Living Primates. Pogonias Press. p. 114. ISBN 0-9648825-0-7.
  11. Wainwright, M. (2002). The Natural History of Costa Rican Mammals. Zona Tropical. pp. 146–149. ISBN 0-9705678-1-2.
  12. Campbell, C. & Gibson, K. (2008). "Spider monkey reproduction and sexual behavior". In Campbell, C.. Spider Monkeys. Cambridge University Press. pp. 266–283. ISBN 978-0-521-86750-4.



יום שבת, 2 ביולי 2011

Carpe diem, quam minimum credula postero

I find that the most exuberant and durable characteristic of life is the taste of new experiences. I have repeatedly heard the claim that pleasures which are conveyed by the 5 elementary senses are 'materialistic, shallow and evanescent'. I disagree with that view and feel somewhat obliged to share the reason.

Our senses are mere appendices of our bodies and, as is the case with any living system on earth, are set upon an inevitable course towards their demise. In addition, every chronological step entails their deterioration. That means less experience gained, in diminished quality. If we are to grasp the rich diversity of this world, we need to act fast.

As an atheist, I believe that there's nothing beyond the looking glass. We only have one shot at this. No afterlife, no heaven or hell, no reincarnation. This is it. This worldview affects me in 2 main ways: Firstly, it makes death much more vivid and critical. Secondly, it enhances every moment, rendering every second priceless. Therefore, I want to use every possible moment to learn, experience and feel.

Of course, I don't mean to suggest that we embark with panic upon a stampede. It is nothing short of insane to keep death in our mind at all times. I also don't mean to belittle the value of 'spiritual' means to happiness. I overtly support the stand that one must also nourish the mind from within.

Everything I'm making here is a reminder, that time is of the essence;  life is both short and precious. We should "gather our rosebuds while we may". Because even if this point seems painfully obvious now, as you read these words, you might forget its importance in the course of time.

So in between the office, the lab, the road or anything else - remember to grasp thorns and roses alike and to embrace as many passing moments as humanly possible, paving the road to the great void with lively bricks.


יום רביעי, 29 ביוני 2011

Deliberations on a Moral Landscape


I have recently started reading Sam Harris's book "The Moral Landscape". In it Harris addresses the erroneous notion that science and morality are non-overlapping magisteria. It seems that a major proportion of the world regards science as a discipline that can determine whether we can do certain things but not whether we should do them.

Science is defined as: "a systematic enterprise that builds and organizes knowledge in the form of testable explanations and predictions about the world"1,2,3. Questions of morality exist in a conscious mind. The mind dwells within a brain that comprises approximately 8.5x1010 living cells. Ergo, both the mind and brain rely on the physical scaffoldings of nature which by definition makes them susceptible to scrutiny. Harris suggests, based on that line of reasoning, that science can in principle supply answers to moral issues.

First, according to Harris, we must accept the fact that human suffering and well-being matter. From that everything else follows. From his point of view, morality is intimately interlocked with well-being, almost interchangeably.

That makes me think. It is not very hard to imagine, at least from an evolutionary point of view, the adaptive values that had made the development of "moral mechanisms" preferable. Pleasure, sadness, happiness, anger, envy, vindictiveness etc. All of those emotions have their uses. But it seems to me that my love to biological and medical sciences had rendered me blind to a more practical aspect of reality. I was so busy chasing ultimate explanations that, in my mind, I have diminished the value of proximate explanations to nearly null.

Nowadays, we do not consider moral issues using an evolutionary jargon. We cannot define an action as "good" according to the manner it affects our fitness, being classical or inclusive. Indeed it would seem ludicrous to consider the benefits of, say, contraception in terms of fitness. We make a trade-off in which we intentionally lower our fitness in order to experience immediate pleasure - qui pro quo. It seems to me that Harris has a point and that the value of our "modern fitness" is governed by variables of consciousness, namely well-being and suffering.

Of course, here rises the obvious claim that "not everything the feels good is, in practice, good". We could argue about the definition of 'good' and 'evil' for a long time, but in my opinion, such arguments fall into the category of "malevolent reductionism". When someone says "I'm here", I don't argue with him about the definition of 'here', reminding him about Heisenberg's uncertainty principle and asserting that he has no fixed location to declare. No, I accept his claim within a delineated conceptual zone of agreement. We have no problem doing that with many aspects of our lives: orientation ("I'm here"), design ("this carpet is red"), law ("beyond reasonable doubt"), biology ("this organism is alive"), medicine ("this patient is healthy") etc. Moral issues are no exception.

I'm still far from finishing this book, but I can definitely say that if we do not let our doubts run untamed (yet by no means silenced!) and if we accept both that (a) consciousness is the platform upon which discourse is waged and that (b) well-being and suffering matter, we will be on the right path to a better scientific understanding of morality.


References
  1. "Online dictionary". Merriam-Webster. Retrieved 2009-05-22. "knowledge or a system of knowledge covering general truths or the operation of general laws especially as obtained and tested through scientific method . . . such knowledge or such a system of knowledge concerned with the physical world and its phenomena"
  2. a b c d Popper, Karl (2002) [1959]. The Logic of Scientific Discovery (2nd English ed.). New York, NY: Routledge Classics. p. 3. ISBN 0-415-27844-9. OCLC 59377149.
  3. Wilson, Edward (1999). Consilience: The Unity of Knowledge. New York: Vintage. ISBN 0-679-76867-X.
  4. ^ Ludwik Fleck (1935), Genesis and Development of a Scientific Fact reminds us that before a specific fact 'existed', it had to be created as part of a social agreement within a community.