Copper is my only weakness!

So maybe sperm has a few other weaknesses but the idea that copper kills sperm does have a certain super hero vibe to it, doesn’t it? Anyway, since I’m pursuing a minor in sexuality and gender studies I like to stay updated on things like birth control and women’s health care. I’ve known about IUDs for a long time but now that they have been deemed safer and a healthy option for people who have not yet had children they have risen in popularity so I decided to focus on copper IUDs for a blog post.

How effective are they? Super. The UN published a report that read described a Chilean study, “Fertilized eggs were found in eight of 36 women using no contraceptives, while only one fertilized egg was recovered among 22 users of inert IUDs that contain no copper and none in 43 users of copper IUDs” (IUDs). Family Planning NSW explains, “The copper IUD is at least 99% effective. This means that on average, if 100 women use a copper IUD for one year, one woman could become pregnant while using the IUD” (Copper).

So they’re effective but how do they work? Um… we’re not totally sure. Of course we know that it works by being inserted into the cervix so that any sperm that makes its way up there is killed by the copper and thus prevented from moving into the fallopian tubes to potentially fertilize an egg. That’s pretty basic but as for why or how the copper kills sperm? It’s not clear. I have looked through numerous studies and where all of them were able to describe what the copper does to the sperm – my favorite explanation goes out to the UN, “Many studies have shown copper to act as a spermicide. In a study of the Copper T 200, scientists observed that the sperm heads were detached from the tails in a majority of sperm cells” (IUDs) – none of them explained how the copper created this affect.

As we have learned in class, science is pretty good at observing but it is not always possible to explain.

Sources:

“Copper IUD.” Family Planning NSW. N.p., 2013. Web. 4 Dec. 2015. <http://www.fpnsw.org.au/682847_8.html>.

“IUDs Block Fertilization.” UN News Center. UN, 1996. Web. 04 Dec. 2015. <http://www.un.org/popin/popis/journals/network/network162/blck162.html>.

Well, if you’re looking at it in a tangible or physical sense then… yeah.

Race plays a vital role in historical and modern cultural and political dynamics but what is race really? From a societal perspective this is by no means a simple question to answer. One must take into account the complexity of expectations and stereotypes associated with race, race vs regional identification, institutes of oppression, global and local relations – it is almost impossible to pin down. But when one attempts to observe race from a genetic stand point they may be surprised to find that they find nothing. For all of the cultural and political implications carried by race, the concept just doesn’t appear within our genome, “Dr. Venter and scientists at the National Institutes of Health recently announced that they had put together a draft of the entire sequence of the human genome, and the researchers had unanimously declared, there is only one race — the human race” (Angier).

I have to admit that this sounds uncomfortably close to the sentiment of ‘I don’t see color’. If we take it in that sense then the conversation is extremely short. Instead, let’s look at why this is the case. The article explains that the human species is still very young, mobile, and wide spread that it hasn’t had the chance to truly divide into biological ‘races’ in any other term that topically. This makes it essentially impossible for something such as skin color to appear within the human genome.

When one looks to interpret this, I would encourage them to consider that race – being a social construct – can be changed in the way it manifests. If one recognizes that the position that race has been forced to fill is nothing but words and ideas perhaps we can begin to move forward and improve the status quo.

Sources:

Angier, Natalie. “Do Races Differ? Not Really, DNA Shows.” The New York Times. The New York Times, 22 Aug. 2000. Web. 4 Dec. 2015. <https://partners.nytimes.com/library/national/science/082200sci-genetics-race.html>.

As a Chinese major and someone who has always been interested in language and phonetics I have noticed that the sound of a word can often feel related to its meaning and that words in separate languages with the same meaning can share similar consonant or vowel sounds despite having been developed oceans or mountains away. Realizing that I am not an especially perceptive person, I was sure that someone much smarter than I am must have also picked up on this and investigated it further. I was right. The phenomenon that I just described is called sound symbolism and it is especially easy to notice when one is observing the expression of size in different languages, “In sound symbolism, the sound of words can bring images to our mind – think of pequeño, petit, or kleine (meaning small) as opposed to grande, grand, or gross (meaning large)” (Kannan). Since this crosses so many barriers within humanity, I was drawn to suspect that this must be a natural predisposed tendancy and I am not the only one, “I have proposed that sound symbolism, the non-arbitrary connection between certain classes of speech sounds and the meanings of the words or morphemes they are in, has a biological evolutionary origin” (Ohala).

So if this is an innate outcome, how does it happen and why? Madhuvanthi Kannan suggests that in the case of words describing size it may be the result of the actions of our mouths as we form the words. “When we say grand (French, for large), for example, our mouth expands as if to mimic the size of the object we refer to, whereas, when we say petit, the vocal tract constricts, and the word plants an impression of a tiny object” (Kannan).  I have seen this trend as well while studying Chinese where “da” (大) – a word with a rounded consonant sound and a wide vowel – means “large” and “xiao” (小) – a word that begins with a mouth pinching “sh” sound and ends with a closing “ow” sound – means “small”.

John Ohala suggests an alternative theory in which he believes that it may be linked to an evolutionary development, “Some light is shed on the above patterns from a study by Morton (1977) who examined the kinds of vocalizations some 28 avian and 28 mammalian species use in agonistic displays, i.e., signals given in face-to-face competitive encounters. In all cases it was found that the confident aggressor or threatener emitted a low-pitched vocalization whereas the submissive nonthreatening individual produced a high-pitched sound” (Ohala). This was an easy theory for me to visualize. When I think of a person talking to a baby or consoling a friend, they often raise the pitch of their voice which I agree sounds much more positive and non-threatening. In contrast if I think of people I often think their voices are low and gruff, a much more threatening intonation.

Both of these theories aligned with my experiences in using and studying language but after considering both of them I was left to wonder whether or not Ohala’s theory may have led to the Kannan’s. To me it seems possible that with certain pitches being able to evoke different responses earlier in human evolution that that process may have culminated into similar phonetic sounds when humans developed spoken language.

Sources:

Kannan, Madhuvanthi. “Some Rules of Language Are Wired in the Brain.”Scientific American. Scientific American, 20 Oct. 2015. Web. 4 Dec. 2015.

Ohala, John J. “Sound Symbolism.” Berkeley Linguistics. University of California, Berkeley, n.d. Web. 4 Dec. 2015. <http://www.linguistics.berkeley.edu/~ohala/papers/SEOUL4-symbolism.pdf>.

Bats are a diverse and complicated character within human culture – folk tales speak of bats curdling breast milk, countless films and books have depicted bats as the disguise for hunting vampires, Shakespeare described bats being used for witches’ spells, Chinese legends uphold the bat as a symbol for happiness and good fortune, and the Babylonians believed bats were the physical manifestation of dead souls. However, aside from their cultural presence, bats are a fascinating and sophisticated species.

Vampire bats in particular have developed many unique and extremely specialized behaviors which have allowed them to be a competitive species within the animal kingdom. As pointed out by Dr. Bill Schutt, much of the research conducted on vampire bat behavior has focused on the common vampire bat (Desmodus rotundus) – one of the three species of vampire bats – under the assumption that their behavior could also be attributed to the other two species of vampires: the white winged vampire bat (Diaemus youngi) and the hairy-legged vampire bat (Diphylla ecaudata). Upon further investigation and observation however, Schutt was able to determine that the behaviors in vampire bats were varied and that their feeding behaviors proved to be the most diverse.

In the case of the common vampire, ground hunting is the preferred method for obtaining blood, “One of the reasons for the common vampire’s success is its ability to feed from the ground—and thanks to humans – they have developed a partiality to cows’ blood. This they often obtain while on the ground, from the region behind the cows’ hooves, an area with relatively thin skin and an ample blood supply flowing close to the surface” (Schutt). This behavior has led to distinct physical traits within Desmodus such as strengthened pectorals and elongated thumbs which allow them to jump away from potential kicks by their bovine prey and take flight off the ground.

The white winged vampire is a much daintier species. In contrast to its common vampire cousin, Diaemus prefers to hunt in the trees. By hanging on the branch below a roosting bird the white winged vampire licks the foot or toes of its prey (all vampire bats do this as their saliva acts as an anticoagulant). Once the site prepared, Diaemus bites down and then laps the blood until it is ready to take to the air from the branch (Schutt). This method of hunting has contributed to Diaemus developing smaller thumbs than the afore mentioned Desmodus. A behavior observed from white winged vampires in captivity reveals a layer of cunning to their otherwise polite style of hunting. Schutt explains,

The other bat, however, crept even closer, and then, amazingly, it nuzzled against the hen’s feathery breast. Instead of becoming alarmed or aggressive, the bird seemed to relax. The vampire responded by pushing itself even deeper into what I would later learn was a sensitive section of skin called the brood patch: a feather-free region, densely packed with surface blood vessels, where body heat is efficiently transferred to the hen’s eggs or to her chicks. As I watched, the hen reacted to the bat by fluffing her feathers, hunkering down—and closing her eyes. (Schutt)

The bats had learned to act the part of a chick, in order to calm the hen and gain access to the blood-rich underside of her breast.

The final species of vampire bat, the hairy-legged vampire, is not afraid to get up close to its prey. As Schull witnessed, this vampire hangs from the underside of the chicken and feeds from around the cloaca (contrast to the white wing which hangs from a branch and feeds mainly from the feet).

In each case, it can be seen that the behavior of an animal influences the ways in which they physically develop and alter. Most of the time when I think of evolution changing the physical characteristics of an organism it is in response to external forces like climate, habitat, and predation but in these instances it seems that it was the chosen behavior of the bats that altered their physical adaptations.

Sources:

Schutt, Bill. “The Curious, Bloody Lives of Vampire Bats.” Natural History. Natural History Museum and Magazine, n.d. Web. 3 Dec. 2015.