When choosing our partner, looks play a decisive role. Research has shown that features such as symmetrical faces, good health, or female traits (when it comes to women) might prove quite essential when deciding whether the person in front of us is worth or not taking the risk of starting a relationship.

Love at first sight...or not

Love & Relationships

While physical attraction will never cease to be an essential component of a relationship, it does have strong competition when talking about communication.&nbsp;The fact that both partners share the same language style can only have positive effects on their future together. Language is also a sure means to see if somebody is having the time of their life or just another wasted evening.

The language style on a date

Whenever you go on a date, you tend to pay attention to some aspects more than to others. Therefore, individuals find themselves judging the person across the table by taking into account his or her smell, hairiness, taste of their kiss, and so on.&nbsp;All these do not only provide one with important information about the person's lifestyle, but they also say more than enough about their health and personal habit. So you better pay attention to these details next time you are on a date, as they behave like the other one's signature.

Your partner's personal signature

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Looks aren't everything but love, it would seem, is far from blind. Across cultures and sexes, some features hold greater appeal. "More symmetrical faces do seem to be rated more attractive," says Tamsin Saxton, a senior lecturer at Northumbria University and part of the evolution, perception and behaviour research group. "The theory goes that your genes provide a template for symmetrical bodies, symmetrical face. [When] there's some sort of problem - you get ill or you encounter some problem with the environment - that can sometimes throw the symmetry off a little bit," she says. "So it might be that if you are picking a symmetric partner then you are actually picking somebody whose genes are fairly well suited to the environment around you."
Looks aren't everything but love, it would seem, is far from blind. Across cultures and sexes, <a href="http://www2.psych.ubc.ca/~schaller/Psyc591Readings/Rhodes2006.pdf">some features</a> hold greater appeal. "More symmetrical faces do seem to be rated more attractive," says Tamsin Saxton, a senior lecturer at Northumbria University and part of the evolution, perception and behaviour research group. "The theory goes that your genes provide a template for symmetrical bodies, symmetrical face. [When] there's some sort of problem - you get ill or you encounter some problem with the environment - that can sometimes throw the symmetry off a little bit," she says. "So it might be that if you are picking a symmetric partner then you are actually picking somebody whose genes are fairly well suited to the environment around you."
And while striking faces may sometimes be drop-dead gorgeous, studies have shown we are generally drawn to Mr or Ms Average, whatever our culture. According to scientists including Professor Randy Thornhill from the University of New Mexico, average features could be a sign of genetic diversity and good health.
But is there such a thing as a "type"? Women with feminine features, such as a smaller chin and fuller lips, tend to be deemed <a href="http://beheco.oxfordjournals.org/content/19/4/902.full">more appealing </a>by both sexes, Saxton tells me, but preferences for male features are <a href="http://www.google.co.uk/url?sa=t&amp;rct=j&amp;q=&amp;esrc=s&amp;source=web&amp;cd=8&amp;ved=0CHEQFjAH&amp;url=http%3A%2F%2Fwww.bashour.com%2Ffaces%2Fdocuments%2FBibliography%2FPDF%2FPenton-Voak%2C%2520I.%2520S.%2520--%2520Female%2520preference%2520for%2520male%2520faces%2520changes%2520cyclically%2520--%2520Further%2520evidence.pdf&amp;ei=dXHvUrrnJKGS7AaF8ICYAQ&amp;usg=AFQjCNG8ZZETEx9IHpfEv44mmQb1piMaAA&amp;sig2=ZMUzOfs_l91pE06LOm8ZCQ&amp;bvm=bv.60444564,d.ZGU">far from clear-cut</a>. "When women are more likely to be able to conceive that seems to be the time when they are <a href="http://link.springer.com/article/10.1007/s10508-007-9268-y#">liking more masculine</a> facial features [in men] and also more masculine bodies, voices and male behaviour," says Saxton. So a disaster date might genuinely be a case of right person, wrong time. But it is possible to <a href="http://www.ehbonline.org/article/S1090-5138%2808%2900005-6/abstract">disrupt the trend</a>. "There's a good deal of evidence that use of the hormonal contraception <a href="http://www.sciencedirect.com/science/article/pii/S0169534709002638">pill is associated</a> with greater preference for more feminine male facial features." And it isn't only chemicals sloshing around inside that can tip the balance. "Women seem to prefer more masculine male faces in countries where <a href="http://rspb.royalsocietypublishing.org/content/277/1692/2405.abstract?ijkey=400c564e2849caba14fdffe63abb7c396ec0f87f&amp;keytype2=tf_ipsecsha;">health prospects </a>are poorer," Saxton says.
It seems the suggestion of heroics could also fuel a romance. A <a href="http://alittlelab.stir.ac.uk/pubs/Burriss_09_scars_paid.pdf">study</a> conducted by researchers at Liverpool and Stirling Universities recruited 115 women and 64 men, asking one group to assess images of the opposite sex with digitally added facial scars while another group viewed blemish-free mug shots. The upshot was that women rated slight scarring in a man's face marginally more attractive when considering a short-term fling - men viewed scarring in women with indifference. The researchers say that scarring may be read by women as a sign of masculinity, courage and strength.
But whether or not you are looking for Indiana Jones, good health is a key quality and once again there may be subtle, chemical cues. In 2009 <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2780675/">researchers at St Andrews University</a> asked 54 people to digitally tweak the hue of a selection of male and female Caucasian faces to make them look "healthy", finding that a light yellow tint and pink flush is perceived to be indicative of the hale and hearty. Follow-up collaborative <a href="http://www.ehbonline.org/article/S1090-5138%2810%2900116-9/abstract">studies </a>supported the view that yellow colouring is deemed more attractive across cultures, and <a href="http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0032988">suggested</a> that an increase in the intake of carotenoid pigments, such as those found in fruit and veg, may increase this yellow tint, although other influences can't be ruled out. But, hot or not, your date has only just begun and it's time to make that opening gambit.
<h2>THE CHAT</h2>
<figure> <img src="https://i.guim.co.uk/img/static/sys-images/Guardian/Pix/pictures/2014/2/4/1391530261953/Smartphones-006.jpg?width=300&amp;quality=85&amp;auto=format&amp;fit=max&amp;s=e7dacdf58dbcea44427e763a0b38d8f2"></figure>It turns out, that it is not just what you say, but the way that you say it that flags up a successful date. One such indicator appears to be the use of function words such as personal pronouns, articles and conjunctions.
"The more you use this group of words, called function words, similarly, the more you like each other," says Molly Ireland a psychologist at Texas Tech University. Ireland and her colleagues <a href="http://homepage.psy.utexas.edu/HomePage/Faculty/Pennebaker/Reprints/Ireland_et.al_LSM&amp;relationships.pdf">studied</a> how such words are used by heterosexual men and women by examining 40 speed dates, using special computer programs to analyse the speakers' language. The study found that speed dating couples were more likely to mutually wish to see each other again if their language style matched better. "When two people are matching each other's use of, say, personal pronouns and articles, that means that they are on the same wavelength in terms of how they are connecting their thoughts and how they are thinking about the situation," she says.
So if your date is speaking in a detached fashion, using "the", "it" and "that" often but you are throwing in plenty of "I" and "we", then chances are there is no point swapping numbers. "It's a very strong predictor," says Ireland.
And while talking a lot may point to a good date, Ireland says their study showed it wasn't the strongest factor. "If you are on a date with somebody who is relatively quiet and maybe you are a relatively quiet person, too, that doesn't matter as long as you are using similar speaking styles," she says. According to Ireland it isn't an easy effect to fake - not only is it difficult to consciously pick up on function words but it is also tricky to deliberately manipulate them.
Speed-dating also threw up some interesting observations for researchers at Stanford University who <a href="http://www.funginstitute.berkeley.edu/sites/default/files/2013%20McFarland%20et%20al_Making%20the%20Connection_Social%20Bonding%20in%20Courtship%20Situations.pdf">studied</a> more than 900 heterosexual dates to work out what makes people click. "Dating is just a great way to study what are the linguistic signs more generally of people creating a bond," one of the authors, Dan Jurafsky, explains. "Men tend to choose skinny women and women tend to choose tall men, but you'll be happy to know that even after controlling for these physical characteristics, people's language is still an excellent predictor of whether they clicked."
After analysing voice-recordings from the dates, they found that for couples who reported "clicking", both the men and the women seemed excited. The men varied their volume and laughed more; while women changed both their loudness and pitch. "By contrast, people feeling awkward use more qualifiers - they say "kind of" and "sort of" and "a little bit" a lot," says Jurafsky. "It's as if they are feeling so uncomfortable with the date that they can't even commit to their sentences." Interestingly, however, Jurafsky and colleagues found it was only when the woman felt uncomfortable that both parties failed to report clicking.
And while women preferred men who spoke loudly, sympathised with them and interrupted them, both men and women preferred it when the woman made herself the focus of the conversation. But perhaps it is best to avoid grilling your date. "We found questions were used by women to keep a lagging conversation going, and they were used by men who had nothing to say," the authors wrote.
And bad news chaps - if you're looking for a lady it could be tough. Women were found to report clicking less frequently than men. "The women are the empowered party," says Jurafsky.
<h2>THE LATE NIGHT SMOOCH</h2>
<figure> <img src="https://i.guim.co.uk/img/static/sys-images/Guardian/Pix/pictures/2014/2/4/1391530652909/Kissing-Fish-008.jpg?width=300&amp;quality=85&amp;auto=format&amp;fit=max&amp;s=38d8b14e726f8dde60997dc8232a349a"></figure>If the date works out, a kiss may be on the cards. It's a crucial moment that could fan the flames or snuff out the spark.
"Each of these stages involves closer and closer spatial relationships so you get in close enough where you can actually smell the person," explains Robin Dunbar, Professor of Evolutionary <a href="https://www.theguardian.com/science/psychology">Psychology</a> at the University of Oxford.
And the clues you are picking up, he says, are genetic. "Your smell and your taste are all determined by a particular complex of genes that determine your immune system."
These major histocompatibility complex (MHC) genes are vital in determining how resistant you are to diseases, and have been found to influence the odour of fluids such as saliva, urine and sweat. In a <a href="http://www.coherer.org/pub/mhc.pdf">study</a> conducted by Claus Wedekind from the University of Lausanne, nearly 50 female participants were asked to sniff T-shirts worn for two nights by men and rate the attractiveness of the whiff. The results showed that the women preferred the odour of T-shirts worn by men with a dissimilar MHC type.
While you may look for similarities with your date, when it comes to MHC genes, genetic variety is the spice of life as offspring are likely to have a wider diversity of immune-system genes, enabling them to fight of a host of maladies.
But how can you tell all this from a kiss? "You don't go, 'oh yes that tastes like a different major histocompatibility complex to me'," explains Dunbar. "What you sense it as is you enjoyed it or you didn't enjoy it."
Once again oral contraceptives can cause confusion, with <a href="http://www.ncbi.nlm.nih.gov/pubmed/18700206">studies</a> including those by Craig Roberts at Stirling University showing that women taking the pill seem to prefer men with similar MHC type. "This is a disaster," says Dunbar. "Women's judgment about how much they like a prospective partner or the smell of a prospective partner is completely derailed."
Kissing or sniffing can also help you pick up on other signals. "One of the other cues it is giving you is health, because that is really strongly affected in both your odour and your taste," says Dunbar.
While kissing is common to many cultures other customs, such as "rubbing noses", can also yield such crucial information. But, Dunbar says, the description is misleading. "What they actually do is put their nose next to the other person's nose and breathe in deeply. They are smelling the smell."
But don't worry if your date is doused in perfume or aftershave. A <a href="http://beheco.oxfordjournals.org/content/12/2/140.abstract">study </a>of 137 men and women by Wedekind and Manfred Milinski found that preference for certain scents appears to be correlated with the wearer's MHC genotype. "Everybody assumes you buy perfumes to cover up all your horrid unwashed smells, it's absolutely quite the opposite," Dunbar explains. "You buy the ones that match and enhance your natural smell signature."
And the sizing up process doesn't stop there. Waist-to-hip ratios in women, waist-to-shoulder ratios in men and even hairiness are all being judged over the evening. But if your chemistry clicks, your mouse may never need to click again. Topics
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Looks aren't everything but love, it would seem, is far from blind. Across cultures and sexes, some features hold greater appeal. "More symmetrical faces do seem to be rated more attractive," says Tamsin Saxton, a senior lecturer at Northumbria University and part of the evolution, perception and behaviour research group.

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