Darwin was a product of his time and with his time came the ideas of sexism and racism which were clearly built into his theories. There are some aspects of Darwin's theory about the differences between men and women that can be explained by biology, but overall it is clear that his theory is based on sexist ideas prevalent in the 1800s. Women are expected to be caring, altruistic, maternal and submissive while men are expected to be dominant, aggressive, successful and confident. Most of Darwin's theory regarding the differences between men and women can be explained by social expectations that shaped what is acceptable in society. Recent studies show that women are viewed as emotional sex in all cultures (Crawford and Unger). Darwin says: “[woman] seems to differ from man in mental disposition, chiefly in her greater tenderness and her less selfishness; and this also applies to savages…” (Darwin 234). This is simply an observation of the socially imposed standards that Darwin considers evolutionary traits. Darwin's hypothesis about mental dispositions leading to differences in male and female attitudes can be explained by stereotypes instilled in people. Gender stereotypes begin to form in children by age five and are typically fully entrenched by the end of adolescence (Crawford and Unger). Women are expected to be tender and considerate of others, as well as submissive. While none of this means that stereotyping is bad, as it is a normal process, it simply explains why this is due to social and not biological factors. A study was conducted to see people's reactions to the angry and sad faces of men and women. women. When these two faces merged together, as in, the angry woman and the sad woman merged… in the center of the card… they find themselves in an unpleasant situation while the women do not (Crawford and Unger). Since men tend to feel more uncomfortable, they simply prefer to reduce their physical reactions by not wanting to face problems. Therefore, the responsibility of maintaining a healthy relationship may fall under the woman's duty. “It is not probable that man's greater strength was acquired chiefly through the inherited effects of his having worked harder than woman for his own subsistence and that of his family; for women in all barbarous nations are forced to work at least as hard as men” (234). Men can usually be stronger than women, but that's not necessarily always true. Women could be as strong as men if cultural and beauty standards were different and if that was what women wanted. This idea evolved from implemented social factors rather than evolution or biology.