As proposal. Those biological factors make our

As we know, the attraction is a force between two people or two objects. It is the power could make people more intimate, and further lead to romantic relationships or friendships, and resist their separation. According to this definition, the attraction is as same as the romantic love in animals, which can be characterized by increased energy, romantic gestured, and obsessed with a specific mate. In a biological way, the researchers found two elements in human blood can make attraction. One of them is the adrenalin, which can make your heart beat faster, your palms get sweaty, and your mouth gets dry. The other one is Serotonin that may be involved in love too. In 2003, Fisher et al argued about the relationship between the neural mechanisms associated with the romantic love. They used the fMRI to scan the participants’ brain and found when participants look at their lover, the dopamine-rich brain area is associated with rewards, motivation, and goal orientation. (http://www.appsychology.com/IB%20Psych/IBcontent/Studies/Fisher.htm)The results show that the existence of the brain circuit is to attract. The same brain circuit is also associated with “addiction”, which may support the assumption that “romantic love is an addiction.” However, the Passionate Love Scale is not accurate because the participant could lie about the questionnaire. what’s more, there is researcher bias and ethical issue. The other evolutionary explanation is partner selection based on genes. Weekend (1995) utilized the sweaty t-shirt to investigate the mate preferences based on the genetic makeup of immune system function. This experiment supports the evolutionary interpretation of human spouse choice. Experiments show that attractiveness is affected by biological factors. These women are more likely to have genetic make-up males, which may increase the health of potential infants. But evolutionary theory can not explain the attraction and love between same-sex couples because the relationship is not created for the generation of offspring. Also, culture plays an important role in attraction, which is a big error in this proposal. Those biological factors make our body in response to the true love.
What’s more, every time when we talked about the romantic love, that always brings me back to psychological origins of attraction. Burne(1971) posed a hypothesis that people are like to attract the person who shared the similar trait to themselves. Because people can boost their self-esteem when they are sharing the same value.  As same as Newcomb(1961), he found the students will be easy to build the friendship if they shared the same attitude and value. Even Markey and Markey investigate the undergraduate student personality and their dream partner traits. They found most of the participants wanted a lover similar to themselves. Also, the results suggest that it is important to think that the likelihood of a potential partner is similar, but perhaps this ideal partner is hard to find. A follow-up study of a new study found that romances of love and harmony are more likely to be predominant and obedient. This shows that the complementarity of certain personality factors can have a positive impact on harmony.Those experiments showed that there is a correlation that similarity is a factor to choose a partner. They all used a relatively large sample which means all validates the result. However, their self-selected sample and self-reports lack generalizability and reliability.  Participants may lie about the questionnaire too. Dijkstra and Barelds (2010) conclusion are people tend to view their partner from the current perspective. If they are no longer attracted by their partner, he or she is perceived as different from himself and usually less positive than herself. But their questionnaires might have self-serving bias too.
At last, from the socio-cultural origins of attraction, proximity factors represent physical intimacy is important in attracting. Attractive approaching theory suggests that just being in another’s body increases the likelihood of becoming friends. Festinger et al. (1950) investigate the role of proximity to friendship patterns. The results show that opportunities for intimacy or opportunity to collide with one another in everyday life increase the chances of friendship. In a matter of months, the friendship with people living in the same building has more than tenfold, and the friendship with people living next door has been increasing. Researchers believe that physical contact increases the chances of interaction and thus increases familiarity. Festinger performed interview and observation. But this experiment sample can’t be generalized. Meanwhile, Buss et al. (1990) think in almost all cultures, respondents considered “mutual attraction and love” as the most important relationship. This shows that in a relationship, the desire for each other’s love is more than just a Western phenomenon. But when they are doing this experiment, the study encountered post-translational translation problems in the questionnaire, which may reduce the effectiveness of the results. It has a large sample but the sample of each country is not representative, so it is impossible to generalize these findings. In a word, attraction can be affected by the genes, similarity, and culture factor. Those factors from the biological, psychological, and socio-culture can explain why people get attracted to a special mate.