Drunken Science

In my last post, I talked about the societal impact of alcohol and its place in our everyday culture; today, however, my inner nerd has taken it upon himself to get stuck into the real meat of the question of alcohol, the chemistry and biology of it all, and how all the science fits together.

To a scientist, the word ‘alcohol’ does not refer to a specific substance at all, but rather to a family of chemical compounds containing an oxygen and hydrogen atom bonded to one another (known as an OH group) on the end of a chain of carbon atoms. Different members of the family (or ‘homologous series’, to give it its proper name) have different numbers of carbon atoms and have slightly different physical properties (such as melting point), and they also react chemically to form slightly different compounds. The stuff we drink is that with two carbon atoms in its chain, and is technically known as ethanol.

There are a few things about ethanol that make it special stuff to us humans, and all of them refer to chemical reactions and biological interactions. The first is the formation of it; there are many different types of sugar found in nature (fructose & sucrose are two common examples; the ‘-ose’ ending is what denotes them as sugars), but one of the most common is glucose, with six carbon atoms. This is the substance our body converts starch and other sugars into in order to use for energy or store as glycogen. As such, many biological systems are so primed to convert other sugars into glucose, and it just so happens that when glucose breaks down in the presence of the right enzymes, it forms carbon dioxide and an alcohol; ethanol, to be precise, in a process known as either glycolosis (to a scientist) or fermentation (to everyone else).

Yeast performs this process in order to respire (ie produce energy) anaerobically (in the absence of oxygen), so leading to the two most common cases where this reaction occurs. The first we know as brewing, in which an anaerobic atmosphere is deliberately produced to make alcohol; the other occurs when baking bread. The yeast we put in the bread causes the sugar (ie glucose) in it to produce carbon dioxide, which is what causes the bread to rise since it has been filled with gas, whilst the ethanol tends to boil off in the heat of the baking process. For industrial purposes, ethanol is made by hydrating (reacting with water) an oil by-product called ethene, but the product isn’t generally something you’d want to drink.

But anyway, back to the booze itself, and this time what happens upon its entry into the body. Exactly why alcohol acts as a depressant and intoxicant (if that’s a proper word) is down to a very complex interaction with various parts and receptors of the brain that I am not nearly intelligent enough to understand, let alone explain. However, what I can explain is what happens when the body gets round to breaking the alcohol down and getting rid of the stuff. This takes place in the liver, an amazing organ that performs hundreds of jobs within the body and contains a vast repetoir of enzymes. One of these is known as alcohol dehydrogenase, which has the task of oxidising the alcohol (not a simple task, and one impossible without enzymes) into something the body can get rid of. However, most ethanol we drink is what is known as a primary alcohol (meaning the OH group is on the end of the carbon chain), and this causes it to oxidise in two stages, only the first of which can be done using alcohol dehydrogenase. This process converts the alcohol into an aldehyde (with an oxygen chemically double-bonded to the carbon where the OH group was), which in the case of ethanol is called acetaldehyde (or ethanal). This molecule cannot be broken down straight away, and instead gets itself lodged in the body’s tissues in such a way (thanks to its shape) to produce mild toxins, activate our immune system and make us feel generally lousy. This is also known as having a hangover, and only ends when the body is able to complete the second stage of the oxidation process and convert the acetaldehyde into acetic acid, which the body can get rid of relatively easily. Acetic acid is commonly known as the active ingredient in vinegar, which is why alcoholics smell so bad and are often said to be ‘pickled’.

This process occurs in the same way when other alcohols enter the body, but ethanol is unique in how harmless (relatively speaking) its aldehyde is. Methanol, for example, can also be oxidised by alcohol dehydrogenase, but the aldehyde it produces (officially called methanal) is commonly known as formaldehyde; a highly toxic substance used in preservation work and as a disinfectant that will quickly poison the body. It is for this reason that methanol is present in the fuel commonly known as ‘meths’- ethanol actually produces more energy per gram and makes up 90% of the fuel by volume, but since it is cheaper than most alcoholic drinks the toxic methanol is put in to prevent it being drunk by severely desperate alcoholics. Not that it stops many of them; methanol poisoning is a leading cause of death among many homeless people.

Homeless people were also responsible for a major discovery in the field of alcohol research, concerning the causes of alcoholism. For many years it was thought that alcoholics were purely addicts mentally rather than biologically, and had just ‘let it get to them’, but some years ago a young student (I believe she was Canadian, but certainty of that fact and her name both escape me) was looking for some fresh cadavers for her PhD research. She went to the police and asked if she could use the bodies of the various dead homeless people who they found on their morning beats, and when she started dissecting them she noticed signs of a compound in them that was known to be linked to heroin addiction. She mentioned to a friend that all these people appeared to be on heroin, but her friend said that these people barely had enough to buy drink, let alone something as expensive as heroin. This young doctor-to-be realised she might be onto something here, and changed the focus of her research onto studying how alcohol was broken down by different bodies, and discovered something quite astonishing. Inside serious alcoholics, ethanol was being broken down into this substance previously only linked to heroin addiction, leading her to believe that for some unlucky people, the behaviour of their bodies made alcohol as addictive to them as heroin was to others. Whilst this research has by no means settled the issue, it did demonstrate two important facts; firstly, that whilst alcoholism certainly has some links to mental issues, it is also fundamentally biological and genetic by nature and cannot be solely put down as the fault of the victim’s brain. Secondly, it ‘sciencified’ (my apologies to grammar nazis everywhere for making that word up) a fact already known by many reformed drinkers; that when a former alcoholic stops drinking, they can never go back. Not even one drink. There can be no ‘just having one’, or drinking socially with friends, because if one more drink hits their body, deprived for so long, there’s a very good chance it could kill them.

Still, that’s not a reason to get totally down about alcohol, for two very good reasons. The first of these comes from some (admittely rather spurious) research suggesting that ‘addictive personalities’, including alcoholics, are far more likely to do well in life, have good jobs and overall succeed; alcoholics are, by nature, present at the top as well as the bottom of our society. The other concerns the one bit of science I haven’t tried to explain here- your body is remarkably good at dealing with alcohol, and we all know it can make us feel better, so if only for your mental health a little drink now and then isn’t an all bad thing after all. And anyway, it makes for some killer YouTube videos…

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Studying homosexuality

For part two of this multi-parter on sex & sexuality in one form of another, I would like to turn to the topic that first inspired this series in the first place: homosexuality. This is a subject that is notoriously hard to talk about without offending or angering one group or another, but I’m going to try and consider the subject (please tell me off if I ever refer to it as a problem) objectively, trying to analyse it as a concept. Not that this means I won’t end up using the wrong words at one point or another, but try to believe me when I say I’m not trying to.

From an evolutionary perspective, being gay doesn’t make much sense. Natural selection as a way of ensuring the ‘success’ of a species relies upon passing on genes to the next generation, and this clearly isn’t going to happen if the psychological imperative of a person is to mate with someone who they cannot have children with. It would seem, therefore, that since homosexuality is something not evolutionarily favoured, that it should have died out several million years ago, but this is patently not the case. This makes its root cause something of a poser- not being evolutionarily selected for would seem to root out any genetic cause, but it doesn’t appear to be simply a feature of just our modern society (both Leonardo da Vinci and King William II were probably gay) or even solely our species (bats, dolphins and lions are among a huge group of other animals to display homosexual behaviour). It’s not as if these are isolated cases either- between 8 and 15% of gulls on the Santa Barbara coast practice lesbian mating, and all bonobos (the smallest of the great apes) are bisexual. Compare this to the oft-quoted figure that 10% of human beings are gay, or even some of the other estimates that have been put about; I have heard it claimed that one third of British women are either lesbian or bisexual, whilst Alfred Kinsey, inventor of the notorious Kinsey Scale of Heterosexual-Homosexual Rating (o being totally hetero, 6 totally homo, 1-5 being various degrees of in between) claimed that less than 5% of people were exactly 0 or 6.

Homosexuality is, therefore, clearly nothing new, and from mere observation can certainly not be called ‘unnatural’. Indeed, for those of us who are gay, it clearly feels like the more ‘natural’ way of doing things. Just as the rest of us become attracted to and fall in love with someone in what is perceived the ‘normal’ way, so the precise same procedure is performed by homosexuals, the only difference (of course) being that their objects of affection are of their own gender. The fundamental difference is, then, simply a question of finding the ‘wrong’ group of people attractive compared to the norm, although exactly how and why this difference occurs is still a conundrum that has flummoxed far finer minds than mind.

So, if homosexuality has always formed a part of our existence, why has it attracted all the various degrees of hate that it has over the years? This, at least, we can clearly call a societal thing- the ancient Greeks are famous for their acceptance of homosexuality as a form of love (the Spartans even considering it the highest form), and since it is at least tolerated where else it occurs in the animal kingdom we must presume that the hating of it is something that has sadly developed within human culture. Among teenage boys especially, the very idea of homosexuality is considered kinda disgusting, presumably mostly because it appears so alien to the burgeoning sexual emotions of the majority of them. Then we encounter the fact that wanting to have sex with a man is a ‘naturally’ female trait, and since women have generally been shoved firmly into subservient positions for most of human history this does not hold well for the prospect of homosexuality gaining societal respect. It has also been postulated that the motions of male homosexual intercourse, requiring one of the men to adopt a submissive position and accept the penetration of an orifice that (let’s face it) wasn’t designed for the purpose, is quite a humiliating idea, further enhancing the level of disgust, and making homosexuality just seem ‘wrong’ to many, especially men, from quite a young age. Since young men who generally don’t get told what to do or think have historically tended to take up positions of power (ie sons of important people who tend to follow in their father’s footsteps), this has meant these burgeoning ideas are allowed to remain untempered and find their way into the upper echelons of society. From there, by means of both law (homosexuality has frequent been made illegal in various countries from time to time, when they ever acknowledged it actually exists) or religion (the Catholic Church render any further expansion of this point unnecessary), such views filter down and further reinforce the idea of it all being ‘wrong’. From there, persecution is merely a formality.

OK so… why is this persecution generally aimed at men? This one’s comparatively simple to answer, and the reason is twofold. Firstly, women have, as previously mentioned, tended to be considered less important then men throughout history and lesbian exploits have thus been less likely to be of any societal importance than those of their male counterparts. Secondly… well basically, straight men have tended to be in charge and set the rules, and straight men find lesbians sexy. And I’m not even going to try analysing that particular fact.

I’m not really aiming to try and draw any meaningful conclusions from this post, just to throw around a few ideas and explore a concept or two. Next post I’ll be sticking to another broadly sex-related theme, although I can’t tell you which as I have absolutely no idea.

Icky stuff

OK guys, time for another multi-part series (always a good fallback when I’m short of ideas). Actually, this one started out as just an idea for a single post about homosexuality, but when thinking about how much background stuff I’d have to stick in for the argument to make sense, I thought I might as well dedicate an entire post to background and see what I could do with it from there. So, here comes said background: an entire post on the subject of sex.

The biological history of sex must really start by considering the history of biological reproduction. Reproduction is a vital part of the experience of life for all species, a necessary feature for something to be classified ‘life’, and among some thinkers is their only reason for existence in the first place. In order to be successful by any measure, a species must exist; in order to exist, those of the species who die must be replaced, and in order for this to occur, the species must reproduce. The earliest form of reproduction, occurring amongst the earliest single-celled life forms, was binary fission, a basic form of asexual reproduction whereby the internal structure of the organism is replicated, and it then splits in two to create two organisms with identical genetic makeup. This is an efficient way of expanding a population size very quickly, but it has its flaws. For one thing, it does not create any variation in the genetics of a population, meaning what kills one stands a very good chance of destroying the entire population; all genetic diversity is dependent on random mutations. For another, it is only really suitable for single-celled organisms such as bacteria, as trying to split up a multi-celled organism once all the data has been replicated is a complicated geometric task. Other organisms have tried other methods of reproducing asexually, such as budding in yeast, but about 1 billion years ago an incredibly strange piece of genetic mutation must have taken place, possibly among several different organisms at once. Nobody knows exactly what happened, but one type of organism began requiring the genetic data from two, rather than one, different creatures, and thus was sexual reproduction, both metaphorically and literally, born.

Just about every complex organism alive on Earth today now uses this system in one form or another (although some can reproduce asexually as well, or self-fertilise), and it’s easy to see why. It may be a more complicated system, far harder to execute, but by naturally varying the genetic makeup of a species it makes the species as a whole far more resistant to external factors such as disease- natural selection being demonstrated at its finest. Perhaps is most basic form is that adopted by aquatic animals such as most fish and lobster- both will simply spray their eggs and sperm into the water (usually as a group at roughly the same time and place to increase the chance of conception) and leave them to mix and fertilise one another. The zygotes are then left to grow into adults of their own accord- a lot are of course lost to predators, representing a huge loss in terms of inputted energy, but the sheer number of fertilised eggs still produces a healthy population. It is interesting to note that this most basic of reproductive methods, performed in a similar matter by plants, is performed by such complex animals as fish (although their place on the evolutionary ladder is both confusing and uncertain), whilst supposedly more ‘basic’ animals such as molluscs have some of the weirdest and most elaborate courtship and mating rituals on earth (seriously, YouTube ‘snail mating’. That shit’s weird)

Over time, the process of mating and breeding in the animal kingdom has grown more and more complicated. Exactly why the male testes & penis and the female vagina developed in the way they did is unclear from an evolutionary perspective, but since most animals appear to use a broadly similar system (males have an appendage, females have a depository) we can presume this was just how it started off and things haven’t changed much since. Most vertebrates and insects have distinct sexes and mate via internal fertilisation of a female’s eggs, in many cases by several different males to enhance genetic diversity. However, many species also take the approach that ensuring they care for their offspring for some portion of their development is a worthwhile trade-off in terms of energy when compared to the advantages of giving them the best possible chance in life. This care generally (but not always, perhaps most notably in seahorses) is the role of the mother, males having usually buggered off after mating to leave mother & baby well alone, and the general ‘attitude’ of such an approach gives a species, especially females, a vested interest in ensuring their baby is as well-prepared as possible. This manifests itself in the process of a female choosing her partner prior to mating. Natural selection dictates that females who pick characteristics in males that result in successful offspring, good at surviving, are more likely to pass on their genes and the same attraction towards those characteristics, so over time these traits become ‘attractive’ to all females of a species. These traits tend to be strength-related, since strong creatures are generally better at competing for food and such, hence the fact that most pre-mating procedures involve a fight or physical contest of some sort between males to allow them to take their pick of available females. This is also why strong, muscular men are considered attractive to women among the human race, even though these people may not always be the most suitable to father their children for various reasons (although one could counter this by saying that they are more likely to produce children capable of surviving the coming zombie apocalypse). Sexual selection on the other hand is to blame for the fact that sex is so enjoyable- members of a species who enjoy sex are more likely to perform it more often, making them more likely to conceive and thus pass on their genes, hence the massive hit of endorphins our bodies experience both during and post sexual activity.

Broadly speaking then, we come to the ‘sex situation’ we have now- we mate by sticking penises in vaginas to allow sperm and egg to meet, and women generally tend to pick men who they find ‘attractive’ because it is traditionally an evolutionary advantage, as is the fact that we find sex as a whole fun. Clearly, however, the whole situation is a good deal more complicated than just this… but what is a multi parter for otherwise?