Biological factors are something that contributes hugely to the formation and maintenance of relationships- whether it is romantic, friendly or family related. Many researchers have conducted studies in which they have attempted to try and explain the link between biological factors and human relationships. I am going to specifically focus on Bowlby’s study on the role of hormones in bonding, Buss’ study on women jealousy and its relation to estrogen levels, Fishers study on the brain and its role in romantic relationships, and Marazziti who studied the effect of serotonin on love obsession. These studies will help me show the role that biological factors have in human relationships in both the development and maintenance of them.
So when oestrogen levels are low, women tend to be more sexually jealous where as when the oestrogen levels are relatively high women tend to be more emotionally jealous. This helped to set the base of his argument that “human sexual behaviour is grounded in the need to optimize the potential for reproduction, with the goal of the best genetic combination possible for the offspring, as well as maximizing parental care after a birth.” When he did his study in 1993 he found that women and men in regions of the world with high levels of pathogen stress rated the importance of physical attractiveness. For this study there was a huge amount of gender bias as he tends to favor men and only criticizes women… This gives an uneven weighting and unreliable results from the research. Also he made generalizations that cant be made as different people have different personalities. Due to these criticisms, there can be hints at possibilities on his theories of this biological factors affect on human relationships however it is not something that has been proven.

Finally, Fishers research in 2001was a conducted study using FMRI (functioning magnetic resonance imaging) to analyze and examine the impact of the brain on romantic love. He took a large sample of young couples to test in this experiment. He took each person individually into the