Love is a many-splendored thing, according to experts. As someone who considers themselves a scientist and, depending on how many glasses of wine I have had, someone who has been in love, this week of all weeks I couldn’t help but wonder, what exactly is love? Does it benefit us as a species? Is it an evolutionary hangover regarding altruism and mating preference, skewered by social etiquette? Or is it selfishness, projected on someone as a need to be with them, but in reality an obsession to obtain their gametes for you, and only you, and not share these amazing genes with anyone else? These certainly cross my mind whenever I am eyeing up someone in Metric, but for others it may not be as crystal clear.

And when I mean love, what exactly do I mean? The love I am referring to is the sort that caused Ryan Gosling to grow a beard and build that house. The sort that made Joseph Gordon-Levitt stroll into the park and sing and dance with what didn’t seem like a coincidental arrangement of people for a Saturday morning. The sort of love that when Dumbledore asked, “After all this time?” made Snape reply, “Always.” I don’t mean the love between a mother and her daughter, a man and his dog, or a biologist and their agar plates. These are still legitimate forces of adoration and come under the large umbrella of the term love too, but in this case, it is romantic love that seems to need the constant dissection to understand it or justify behaviour done in the name of love.

This love is explained not so delicately by Helen Fisher, an anthropologist, but a scientist nonetheless. She sorts the progression of love into three discrete but not necessarily independent stages; lust, attraction, and attachment. These three are not listed in chronological order in terms of a romantic relationship’s development as they are very much interchangeable. Each of these three stages comes with different boosts of hormones throughout the brain, to accommodate the different life strategies that are optimal for different stages in mammalian reproduction. Love is literally all in your head, although it can cause the usual racing of the heart, sweating of the palms or high quantities of alcohol ingestion too (or possibly chlamydia).

For example, lust accommodates the sex drive and the wish to mate and reproduce recklessly and repeatedly, regardless of where said mate lies on the Imperial scale. It is associated with oestrogens and androgens – hormones that work for the reproductive side of things in the body, and are regulated within the hypothalamus. It is purelya chemical surge to want to get hot and heavy very suddenly, and can subside as quickly as it came (one orgasm joke in the bag). This neurological wiring is completely independent of attraction, which can explain just how easy it can be at times to kick that rugby guy out of your bed after a drunken night out.

Attraction, however, is associated with catecholamines (organic compounds) like dopamine, which can act as neuromodulators – that is, they induce prolonged, neurologically derived emotive incentives to want someone, and that person only. It was pointed out by the big man himself, Darwin, that attraction facilitates mating preference as opposed to just mating alone (a masturbation joke? You decide). Heightened levels of these hormones are linked to the “reward centres” of the brain, making you think that the obsession you are nurturing is a great thing, as monogamous mating seems apt for bringing up the offspring of Homo sapiens, among others.

Attraction is the part where you consider the partner to be able to suit both yourself and your possible offspring in emotive traits and physical traits needed for resource acquisition and prolonged companionship. Intense attraction is considered to be this “love thing” people get upset about, and Fisher ruthlessly lists what psychological properties are associated with this stage of hormonal peaks – intrusive thinking about this person, a longing for emotional reciprocity, a feeling of uncontrollable passion, the eagerness to reorder daily priorities to be available to this loved person and the willingness to sacrifice for them…the list goes on and on.

Ever found yourself finishing revision half an hour early to buy that special someone a jacket potato in the library café?

Although such a list reads like Sheldon Cooper’s diary entries as opposed to that Valentine’s card you probably won’t be getting, no doubt it will resonate with some of the more love-struck students out there. Ever found yourself finishing revision half an hour early to buy that special someone a jacket potato in the Library Café? You might be in love mate. This is the selfish element of love – and if it is requited can solidify a mating pair for optimal offspring survival and make sure no-one else steals those golden gametes.

Finally, attachment is associated with long term companionship. Linked to oxytocin and vasopressin release in the hypothalamus of the brain, these act to maintain monogamous attachments between organisms and encourages mutual parental behaviour. This stage does bode well if it follows the lust of actually making a baby, then the attraction needed to keep the parents together through the pregnancy, but it doesn’t necessarily have to be so. It has been suggested that this is the case for successful arranged marriages, or even in long lasting friendship. Even without the hormonal surges associated with lust and attraction, such couples can sustain a happy family environment regardless of not being hopeless fools or copulating like horny teenagers at some point.

So with this little guide to the science behind love now in your hands, please refrain from using it as some sort of aid to pick up girls after a few too many pints. No girl wants to hear how you can trigger oestrogen release in her in the shortest time ever. The same goes to lovestruck girls; please don’t attempt to tell that guy whose back of head you have been staring at in lectures for most of last term that he gets your catecholamine level soaring.

Declaring love seems to work well by doing so through poetry, literature, interpretive dance, or even via tequila shots. So depending on your audience, consider using these methods instead this Valentine’s Day to snag yourself a date, but feel free to keep in mind what might be going on under the skin too. However, if I do find a card in my locker declaring how you want to grow old with me and stimulate vasopressin release within me, don’t think I will be put off too much either.