A characteristic, such as breast development, voice pitch, or facial hair, that distinguishes the sexes from each other but is not directly concerned with reproduction. The appearance of these characteristics is influenced by hormones. Words nearby secondary sex characteristic secondary road , secondary saturation , secondary school , secondary sensory nucleus , secondary seventh chord , secondary sex characteristic , secondary sexual characteristic , secondary spermatocyte , secondary storage , secondary stress , secondary structure. Origin of secondary sex characteristic First recorded in — Also called secondary sex character. Any of the physical traits in a sexually mature animal that are specific to one sex but are not directly involved in the act of reproducing. Secondary sex characteristics are thought to have evolved to give an individual an advantage in mating by making the individual more attractive to mates or by allowing the individual to defeat rivals in competition for mates. Some secondary sex characteristics include the facial hair of the human male, the relatively prominent breasts of the human female, the antlers found only in the male of most species of deer, and the colorful plumage of the males of many species of birds. The appearance of secondary sex characteristics is determined by the sex hormones. See more at sexual selection.
Secondary sex characteristics are features which make it possible to tell the sexes of a species apart. They are not directly linked to reproduction. Male birds usually have much more colourful feathers plumage , the females are usually better able to hide, because their plumage is camouflaged. Well-known secondary sex characteristics in humans are the deeper voice, facial hair mustache and beard and more muscular build in men. Faces , generally, make a big impact. It is the part other people interact with. However, the wider hips are needed to give birth. Babies are born through the space between the three bones of a woman's pelvis. So is doubtful to call this a secondary characteristic, except so far as the width helps attract mates. Breasts are also essential, but in humans they are much larger in proportion to other mammals , and they do serve to attract males.
As a member, you'll also get unlimited access to over 79, lessons in math, English, science, history, and more. Plus, get practice tests, quizzes, and personalized coaching to help you succeed. Already registered? Log in here for access. Log in or sign up to add this lesson to a Custom Course. Log in or Sign up. Jim has a master's degree in secondary Education and has taught English from middle school level to college. Have you ever really considered the differences between males and females in various species? If you have, you may have noticed the differences in physical traits between the two sexes. Without even realizing it, you were likely thinking about both primary and secondary characteristics.
While primary sex characteristics are those that are present at birth, secondary sex characteristics are those that appear during puberty. These secondary sex characteristics are caused by hormones released at the time of puberty, which usually is around two years earlier in girls than in boys. While both boys and girls grow taller in their teenage years, the male body becomes more muscular, and the shoulders grow broader than the hips, while the female's hips become wider than her shoulders, and breasts develop.
Some of the first changes in a boy are the growth of his testicles and growth of pubic hair. Later, the chest becomes larger, hair grows in the armpits, muscles grow in the arms and legs and shoulders become larger and stronger. In some males, hair also grows on the chest, but generally, Asian men are less hairy and less muscular than Caucasian men, and those from Africa have coarser body hair.
Facial hair, which usually grows first above the lips and later grows on the cheeks, may grow into a mustache and beard unless the boy shaves regularly. The larynx voice box becomes larger as well, resulting in a deeper voice. In girls, pubic hair begins to grow, followed by underarm hair; breasts develop, with the areola around the nipple becoming darker. Fat deposits around the hips and buttocks also contribute to the female's more rounded appearance. Although the menstrual cycle begins, it may be irregular, with some monthly cycles occurring without ovulation.
Since , menstruation has been beginning a few months earlier every decade, possibly due to better nutrition or to the consumption of meat that contains hormones. In general, girls gain less height and weight than boys do during their teenage years. How Female Puberty Works. How Male Puberty Works. What are the signs of puberty? Puberty How Female Puberty Works.