By Emer Maguire

07 June 2018 - 08:00

Bee pollinating a purple flower
'Society tells us romance is responsible for relationships. The truth is, it’s all down to science – a captivating cocktail of chemistry, genetics, biology and evolution.' Photo ©

Capri23auto licensed under CC0 1.0 and adapted from the original.

Is love truly a drug? And are looks really that important? Science communicator Emer Maguire talks us through love's three stages.

The elusive emotion of love is the foundation of human existence as we know it. Everyone from The Beatles to Ed Sheeran sang about it. Movies celebrate it. The whole world seems to be looking for it. Some of us find it several times, and some of us never do. 

Society tells us romance is responsible for relationships. The truth is, it’s all down to science – a captivating cocktail of chemistry, genetics, biology and evolution.

After suffering the side effects of love myself for some time, I decided to delve further into the science behind it. In my exploration, I found that the anthropologist and love guru Dr Helen Fisher  has split love into three distinct stages.

Stage one – lust

We begin with lust, the fun-filled and flirting-fuelled first stage. At puberty, two sex hormones become active in our bodies – oestrogen and testosterone. Suddenly we find ourselves preoccupied with the urge to find someone to reproduce with. 

Have you ever been in a club and someone makes eye contact with you across a crowded bar? If so, congratulations! That means you have engaged in the age old flirting ritual, the copulatory gaze. This intimate eye contact ignites an animalistic part of the human brain, giving us two choices – approach or retreat. If the feeling is mutual, feel free to approach your new beau. If not, back away slowly.

We humans are relatively good at dealing with unrequited lust. However, animals aren’t quite so tactful. Take the flirty male wolf spider for example. If he approaches an unwilling female, she doesn’t simply retreat – she eats him! So don’t feel too bad the next time you’re rejected. It could be a lot worse. 

It can take our brains less than a second to decide if we are attracted to someone or not. 

A glimmer of hope for the less attractive amongst us – studies  show that a good flirting technique is more important than good looks. So even if you haven’t been blessed with Hollywood looks, you can make up for it with charm and flirty banter. You may think flirting is just a bit of fun, but have you ever stopped to think that it’s fundamental to the continuation of the human race?

One thing that can spark our interest in someone is their natural scent. We have a group of genes called the MHC (major histocompatibility complex) genes. They control our immune system, and they also give us our natural scent.

There was a famous experiment by the Swiss researcher Claus Wedekind, which was equal parts gross and genius. Woman had to smell sweaty t-shirts that men had worn for a couple of days, and then rate the smell in terms of its pleasantness, intensity and sexiness (the things we do for science). Women overwhelmingly preferred the smell of t-shirts worn by men with different MHC genes to their own.

Why? Well, two people with different MHC genes, and therefore different immune systems, could produce a child whose immune system can better fight disease.

Stage two – romantic attraction

Once you make your way through all the flirting and fancying of stage one, you can move to stage two –romantic attraction. This is the stage where you are madly in love. Think fireworks, Romeo and Juliet, rose tinted glasses, butterflies-in-the-tummy kind of love. Your new love is all you can think about and talk about, much to the annoyance of everyone else around you.

Can we explain such euphoric and romantic feelings through science? In short, yes.

People associate love with the heart, but the real magic happens in the brain. Researcher Lucy Brown, along with Dr Helen Fisher, placed people who were madly in love into an MRI scanner. Several areas of the brain lit up, indicating increased blood flow and activity within those areas.

One of the areas is the caudate nucleus, an area that helps us expect and detect rewards. The reward in this case is, of course, love. The second area to light up is the ventral tegmental area. It acts like a chemical factory. Like our own personal cupid, it shoots arrows laced with love drugs into our vulnerable brains and bodies. These love drugs are adrenaline, dopamine and oxytocin, which are released alongside lowering serotonin levels. This chemical cocktail stimulates the same area of the brain as cocaine – with similar side effects. You may have an increased heart rate, obsessive thoughts, and ultimately, addiction. 

Unfortunately for the majority of us, the honeymoon stage comes to an end at some point. Why? Our brains cannot survive in such a blissful, drugged-up state forever. Instead, it sobers up, guiding us to our next stage.

Stage three – attachment

Welcome to stage three – attachment. You are now in this relationship for the long haul. Whether it’s a mortgage, a marriage, getting an adorable puppy together or having a couple of kids, you’re pretty sure you and your other half are long-term lovers.

The brain reacts with a dose of oxytocin, the love hormone. It acts like the glue in a long-term relationship. In terms of evolution, it may have been helpful to be stuck with your partner long enough to create and raise offspring to help our species survive.

For those of you who are lucky enough to make it through the three stages of love, congratulations! But don’t thank romance – thank science.

Emer Maguire is a neurosciences speech and language therapist who also has a Masters degree in Clinical Anatomy from Queens University Belfast. She’s a 'stand-up scientist', teaching people about science by making them laugh. In her spare time, she’s a singer-songwriter, wannabe cyclist and serial joker. She recently presented at Sofia Science Festival. 

Emer was crowned the UK’s best science communicator by international competition FameLab, a partnership between British Council and Cheltenham Science Festival, and uses comedy in her talks to inspire curiosity and learning about science. 

Watch the FameLab International Final live on 7 June 2018 and see more FameLab talks on YouTube.

Follow Emer on Twitter @EmerMofficial

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