Adult

Last updated
An adult human male (left) and female (right) Akha cropped hires.JPG
An adult human male (left) and female (right)

An adult is a human or other animal that has reached full growth. [1] The biological definition of the word means an animal reaching sexual maturity and thus capable of reproduction. In the human context, the term adult has meanings associated with social and legal concepts. In contrast to a non-adult or "minor", a legal adult is a person who has attained the age of majority and is therefore regarded as independent, self-sufficient, and responsible. They may also be regarded as a "major". The typical age of attaining legal adulthood is 18, although definition may vary by legal rights, country, and psychological development.

Contents

Human adulthood encompasses psychological adult development. Definitions of adulthood are often inconsistent and contradictory; a person may be biologically an adult, and have adult behavior, but still be treated as a child if they are under the legal age of majority. Conversely, one may legally be an adult but possess none of the maturity and responsibility that may define an adult character.

In different cultures, there are events that relate passing from being a child to becoming an adult or coming of age. This often encompasses the passing a series of tests to demonstrate that a person is prepared for adulthood, or reaching a specified age, sometimes in conjunction with demonstrating preparation. Most modern societies determine legal adulthood based on reaching a legally specified age without requiring a demonstration of physical maturity or preparation for adulthood.

Biological adulthood

Historically and cross-culturally, adulthood has been determined primarily by the start of puberty (the appearance of secondary sex characteristics such as menstruation and the development of breasts in women, ejaculation, the development of facial hair, and a deeper voice in men, and pubic hair in both sexes). [2] [3] In the past, a person usually moved from the status of child directly to the status of adult, often with this shift being marked by some type of coming-of-age test or ceremony. [4] During the Industrial Revolution, children went to work as soon as they could in order to help provide for their family. There was not a huge emphasis on school or education in general. Many children could get a job and were not required to have experience as adults are nowadays. Adulthood, in more recent years, as it has been studied has developed a characteristic list, that goes far beyond just ones physical maturity. [5] These markers for a full, mentally developed, adult include traits of personal responsibilities in multiple aspects of life.

Although few or no established dictionaries provide a definition for the two-word term biological adult, the first definition of adult in multiple dictionaries includes "the stage of the life cycle of an animal after reproductive capacity has been attained". [6] [7] Thus, the base definition of the word adult is the period beginning at physical sexual maturity, which occurs sometime after the onset of puberty. Although this is the primary definition of the base word "adult", the term is also frequently used to refer to social adults. The two-word term biological adult stresses or clarifies that the original definition, based on physical maturity (i.e. having reached reproductive competency), is being used. [8]

The time of puberty varies from child to child, but usually begins between 10 and 12 years old. Girls typically begin the process of puberty at age 10 or 11, and boys at age 11 or 12. [9] [10] [11] Girls generally complete puberty by 15–17, and boys by age 16 or 17. [11] [12] Nutrition, genetics and environment also usually play a part in the onset of puberty. [13] Girls will go through a growth spurt and gain weight in several areas of their body. Boys will go through similar spurts in growth, though it is usually not in a similar style or time frame. This is due to the natural processes of puberty, but genetics also plays a part in how much weight they gain or how much taller they get. [14]

One recent area of debate within the science of brain development is the most likely chronological age for full mental maturity, or indeed, if such an age even exists. Common claims repeated in the media since 2005 (based upon interpretations of imaging data) have commonly suggested an "end-point" of 25, referring to the prefrontal cortex as one area that is not yet fully mature at the age of 18. However, this is based on an interpretation of a brain imaging study by Jay Giedd, dating back to 2004 or 2005, where the only participants were aged up to 21 years, and Giedd assumed this maturing process would be done by the age of 25 years, whereas more recent studies show prefrontal cortex maturation continuing well past the age of 30 years, marking this interpretation as incorrect and outdated. [15] [16] [17] [18] [19] [20] [21]

Legally, adulthood typically means that one has reached the age of majority – when parents lose parental rights and responsibilities regarding the person concerned. [22] Depending on one's jurisdiction, the age of majority may or may not be set independently of and should not be confused with the minimum ages applicable to other activities, such as engaging in a contract, marriage, voting, having a job, serving in the military, buying/possessing firearms, driving, traveling abroad, involvement with alcoholic beverages, smoking, sexual activity, gambling, being a model or actor in pornography, running for president, etc. Admission of a young person to a place may be restricted because of danger for that person, concern that the place may lead the person to immoral behavior, or because of the risk that the young person causes damage (for example, at an exhibition of fragile items).

One can distinguish the legality of acts of a young person, or of enabling a young person to carry out that act, by selling, renting out, showing, permitting entrance, allowing participation, etc. There may be distinction between commercially and socially enabling. Sometimes there is the requirement of supervision by a legal guardian, or just by an adult. Sometimes there is no requirement, but rather a recommendation.

Using the example of pornography, one can distinguish between:

With regard to films with violence, etc.:

The age of majority ranges internationally from ages 15 to 21, with 18 being the most common age. Nigeria, Mali, Democratic Republic of Congo and Cameroon define adulthood at age 15, but marriage of girls at an earlier age is common. [23]

In most of the world, the legal adult age is 18 for most purposes, with some notable exceptions:

  1. The legal age of adulthood in British Columbia, New Brunswick, Newfoundland and Labrador, Northwest Territories, Nova Scotia, Nunavut, and Yukon in Canada is 19 (though there are some exceptions in which Canadians may be considered legal adults in certain situations like sexual consent, which is age 16, and criminal law, federal elections and the military, which is at 18); [24] [25]
  2. The legal age of adulthood in Nebraska and Alabama in the United States is 19. [26]
  3. The legal age of adulthood in South Korea is 19.
  4. The legal age of adulthood in Mississippi and Puerto Rico in the U.S. is 21.

Prior to the 1970s, young people were not classed as adults until 21 in most western nations. For example, in the United States, young citizens could not vote in many elections until 21 until July 1971 when the 26th Amendment passed mandating that the right to vote cannot be abridged for anyone 18 or older. The voting age was lowered in response to the fact that young men between the ages of 18 and 21 were drafted into the army to fight in the Vietnam War, hence the popular slogan "old enough to fight, old enough to vote" [27]

Young people under 21 in the US could also not purchase alcohol, purchase handguns, sign a binding contract, or marry without permission from parents. After the voting age was lowered, many states also moved to lower the drinking age (with most states having a minimum age of 18 or 19) and also to lower the age of legal majority (adulthood) to 18. However, there are legal activities where 18 is not the default age of adulthood. There are still some exceptions where 21 (or even higher) is still the benchmark for certain rights or responsibilities. To name a couple examples, for most states in the US a person is not allowed to rent a vehicle unless they are 25. In the US the Gun Control Act of 1968 prohibits those under 21 from purchasing a handgun from a federally licensed dealer (although federal law makes an exception for individuals between the ages of 18 and 20 to obtain one from a private dealer if state law permits.) [28]

As of July 1984, the National Minimum Drinking Age Act mandated that all states raise their respective drinking ages to 21 to create a uniform standard for legally purchasing, drinking, or publicly possessing alcohol with exceptions made for consumption only in private residences under parental supervision and permission. This was done in response to reduce the number of drunk driving fatalities prevalent among young drivers. States that choose not to comply can lose up to 10% of highway funding. [29]

The Credit Card Act of 2009 imposed tougher safeguards for young adults between the ages of 18 and 20 obtaining a credit card. Young adults under the age of 21 must either have a co-signer 21 or older or show proof (usually a source of income) that they can repay their credit card balance. [30] Unless that requirement is met, one must wait until 21 to be approved for a credit card on their own.

The Affordable Care Act of 2010 expands the age that young adults can remain on their parent's health insurance plan up to age 26. [31]

As of December 2019, the federal government raised the legal age to purchase tobacco and vaping products from 18 to 21. [32] In states where recreational marijuana is legalized, the default age is also 21, though those younger may be able to obtain medical marijuana prescriptions or cards upon seeing a physician. [33]

Gambling also varies from 18 to 21 depending on the state and many rental car companies do not rent cars to those under 21 and have surcharges for drivers under 25 (although this is not codified, and is company policy).

In Quebec, Canada the Quebec legislature in 2020 raised the age one could purchase recreational marijuana from 18 to 21 stepping out of line with most of the country that set a minimum age of 19 (except Alberta, which is 18.) The Quebec government cited the risk that marijuana poses to the brain development of people under 21 as justification for the age raise. [34]

In March 2021, the state of Washington in a 5–4 decision, justices in the Supreme Court of the State of Washington tossed the life without parole sentences of a 19-year-old and a 20-year-old convicted in separate cases of first-degree aggravated murder decades ago, saying, as with juveniles, the court must first consider the age of those under 21 before sentencing them to die behind bars. This comes at a time where there are ongoing debates about whether those between 18 and 20 should be exempted from the death penalty. [35] [36] [37] [38]

In Germany, courts largely sentence defendants under the age of 21 according to juvenile law in a bid to help them reintegrate into society and mete out punishments that fit the crime as well as the offender.

In May 2021, the state of Texas raised the age that one can be an exotic dancer and work and patronize sexually oriented businesses from 18 to 21. [39]

In the UK, there have been many proposals to raise the age that one can buy tobacco from 18 to 21 in an attempt to curb teen and young adult use to get to a "smoke-free" UK by 2030. [40] All of these laws made over the years reflect the growing awareness that young adults, while not children, are still in a transitional stage between adolescence and full adulthood and that there should be policy adjustments or restrictions where necessary, especially where it pertains to activities that carry certain degrees of risk or harm to themselves or others. [41]

At the same time, however, even though the generally accepted age of majority is 18 [42] in most nations, there are rights or privileges afforded to adolescents who have not yet reached legal adulthood. In the United States, youth are able to get a part-time job at 14 provided they have a work permit. At 16, one is able to obtain a driver's permit or license depending on state laws and is able to work most jobs (except ones requiring heavy machinery) and consent to sexual activity (depending on the state). At 17, one is able to enlist in the armed forces with parental consent although they cannot be deployed to be in combat roles until age 18.

The voting age for local elections in most American cities is 18. But in five localities nationwide — four of which are in Maryland — 16 and 17-year-olds are eligible to vote. The cities are Takoma Park, Riverdale, Greenbelt, and Hyattsville. [43]

In 2020, students 16 or older in Oakland, California gained the right to vote in school board elections. There is a growing movement to lower the voting age in the US and many other countries from 18 to 16 in hopes of engaging the youth vote and encouraging greater electoral participation. Some countries already have a voting age of 16 which include Austria, Scotland, Argentina, Brazil, Wales, Cuba, and Ecuador.

In Germany, one can purchase beer and wine at the age of 16 although they cannot purchase spirits or hard liquor until 18. The age of consent in Germany is 14 if both partners are under 18 but at least 14. Sexual activity with a person under 18 is punishable if the adult is a person of authority over the minor in upbringing, education, care, or employment.

Social construction of adulthood

In contrast to biological perspectives of aging and adulthood, social scientists conceptualize adulthood as socially constructed. [44] [45] While aging is an established biological process, the attainment of adulthood is social in its criteria. In contrast to other perspectives that conceptualize aging and the attainment of adulthood as a largely universal development, regardless of context, nation, generation, gender, race, or social class. Social scientists regard these aspects as paramount in cultural definitions of adulthood. [46]

Further evidence of adulthood as a social construction is illustrated by the changing criteria of adulthood over time. Historically, adulthood in the U.S. has rested on completing one's education, moving away from the family of origin, and beginning one's career. [47] [48] [49] Other key historical criteria include entering a marriage and becoming a parent. These criteria are social and subjective; they are organized by gender, race, ethnicity, social class, among other key identity markers. As a result, particular populations feel adult earlier in the life course than do others. [50] [51] [52] [53]

Contemporary experiences of and research on young adults today substitute more seemingly subjective criteria for adulthood which resonate more soundly with young adults' experiences of aging. [51] [54] The criteria are marked by a growing "importance of individualistic criteria and the irrelevance of the demographic markers of normative conceptions of adulthood." [55] In particular, younger cohorts' attainment of adulthood centers on three criteria: gaining a sense of responsibility, independent decision-making, and financial independence. [56] [57]

Jeffrey Arnett, a psychologist and professor at Clark University in Massachusetts, studied the development of adults and argues that there is a new and distinct period of development in between adolescence and adulthood. This stage, which he calls "emerging adulthood", occurs between the ages of 18 and 25. [58] Arnett describes these individuals as able to take some responsibility for their lives, but still not completely feeling like an adult. Arnett articulates five distinct features that are unique to this period of development: identity exploration, feeling in between, instability, self-focus, and having possibilities. [59] Arnett makes it clear that these 5 aspects of emerging adulthood are only relevant during the life stage of emerging adulthood. [60]

The first feature, identity exploration, describes emerging adults making decisions for themselves about their career, education, and love life. This is a time of life when a young person has yet to finalize these decisions but are pondering them, making them feel somewhere in between adolescent and adult. This leads into a second feature of this phase of life—feeling in between. Emerging adults feel that they are taking on responsibilities but do not feel like a 'full' adult quite yet. Next, the instability feature notes that emerging adults often move around after their high school years whether that is to college, friends' houses, or living with a romantic partner, as well as moving back home with their parents/guardians for a time.This moving around often ends once the individual's family and career have been set. Tagging along with the instability feature is having self-focus. Emerging adults, being away from their parental and societal routines, are now able to do what they want when they want and where they want before they are put back into a routine when they start a marriage, family, and career. Arnett's last feature of emerging adulthood, an age of possibilities, characterizes this stage as one where "optimism reigns". [59] These individuals believe they have a good chance of turning out better than their parents did. [59]

Religion

According to Jewish tradition, adulthood is reached at age 13 for Jewish boys and 12 for Jewish girls in accordance with the Bar or Bat Mitzvah; [61] [62] they are expected to demonstrate preparation for adulthood by learning the Torah and other Jewish practices. The Christian Bible and Jewish scripture contain no age requirement for adulthood or marrying, which includes engaging in sexual activity.

The 1983 Code of Canon Law states, "A man before he has completed his sixteenth year of age, and likewise a woman before she has completed her fourteenth year of age, cannot enter a valid marriage". [63] According to The Disappearance of Childhood by Neil Postman, the Christian Church of the Middle Ages considered the age of accountability, when a person could be tried and even executed as an adult, to be age 7. While certain religions have their guidelines on what it means to be an adult, generally speaking, there are trends that occur regarding religiosity as individuals transition from adolescence to adulthood. The role of religion in one's life can impact development during adolescence. [64] The National Library of Medicine (NCBI) highlights some studies that show rates of religiosity declining as people move out of the house and live on their own. Oftentimes when people live on their own, they change their life goals and religion tends to be less important as they discover who they are. Other studies from the NCBI show that as adults get married and have children they settle down, and as they do, there tends to be an increase in religiosity. Everyone's level of religiosity builds at a different pace, meaning that religion relative to adult development varies across cultures and time. [65]

See also

Related Research Articles

<span class="mw-page-title-main">Developmental psychology</span> Scientific study of psychological changes in humans over the course of their lives

Developmental psychology is the scientific study of how and why humans grow, change, and adapt across the course of their lives. Originally concerned with infants and children, the field has expanded to include adolescence, adult development, aging, and the entire lifespan. Developmental psychologists aim to explain how thinking, feeling, and behaviors change throughout life. This field examines change across three major dimensions, which are physical development, cognitive development, and social emotional development. Within these three dimensions are a broad range of topics including motor skills, executive functions, moral understanding, language acquisition, social change, personality, emotional development, self-concept, and identity formation.

Gender dysphoria (GD) is the distress a person experiences due to a mismatch between their gender identity—their personal sense of their own gender—and their sex assigned at birth. The term replaced the previous diagnostic label of gender identity disorder (GID) in 2013 with the release of the diagnostic manual DSM-5. The condition was renamed to remove the stigma associated with the term disorder.

<span class="mw-page-title-main">Adolescence</span> Human transition from puberty to adult

Adolescence is a transitional stage of physical and psychological development that generally occurs during the period from puberty to adulthood. Adolescence is usually associated with the teenage years, but its physical, psychological or cultural expressions may begin earlier or end later. Puberty typically begins during preadolescence, particularly in females. Physical growth and cognitive development can extend past the teens. Age provides only a rough marker of adolescence, and scholars have not agreed upon a precise definition. Some definitions start as early as 10 and end as late 30. The World Health Organization definition officially designates an adolescent as someone between the ages of 10 and 19.

Development of the human body is the process of growth to maturity. The process begins with fertilization, where an egg released from the ovary of a female is penetrated by a sperm cell from a male. The resulting zygote develops through mitosis and cell differentiation, and the resulting embryo then implants in the uterus, where the embryo continues development through a fetal stage until birth. Further growth and development continues after birth, and includes both physical and psychological development that is influenced by genetic, hormonal, environmental and other factors. This continues throughout life: through childhood and adolescence into adulthood.

<span class="mw-page-title-main">Child</span> Human between birth and puberty

A child (pl. children) is a human being between the stages of birth and puberty, or between the developmental period of infancy and puberty. It may also refer to an unborn human being. The legal definition of child generally refers to a minor, otherwise known as a person younger than the age of majority. Children generally have fewer rights and responsibilities than adults. They are generally classed as unable to make serious decisions.

A boy is a young male human. The term is commonly used for a child or an adolescent. When a male human reaches adulthood, he is usually described as a man.

In medicine and the social sciences, a young adult is generally a person in the years following adolescence, sometimes with some overlap. Definitions and opinions on what qualifies as a young adult vary, with works such as Erik Erikson's stages of human development significantly influencing the definition of the term; generally, the term is often used to refer to adults in approximately the age range of 18 to 40 years, with some more inclusive definitions extending the definition into the early to mid 40s. The young adult stage in human development precedes middle adulthood.

<span class="mw-page-title-main">Coming of age</span> Young persons transition from childhood to adulthood

Coming of age is a young person's transition from being a child to being an adult. The specific age at which this transition takes place varies between societies, as does the nature of the change. It can be a simple legal convention or can be part of a ritual or spiritual event.

<span class="mw-page-title-main">Youth</span> Time between childhood and adulthood

Youth is the time of life when one is young. The word, youth, can also mean the time between childhood and adulthood (maturity), but it can also refer to one's peak, in terms of health or the period of life known as being a young adult. Youth is also defined as "the appearance, freshness, vigor, spirit, etc., characteristic of one, who is young". Its definitions of a specific age range varies, as youth is not defined chronologically as a stage that can be tied to specific age ranges; nor can its end point be linked to specific activities, such as taking unpaid work, or having sexual relations.

<span class="mw-page-title-main">Tanner scale</span> Physical development scale of children, adolescents, and adults

The Tanner scale is a scale of physical development as children transition into adolescence and then adulthood. The scale defines physical measurements of development based on external primary and secondary sex characteristics, such as the size of the breasts, genitals, testicular volume, and growth of pubic hair. This scale was first quantified in 1969 by James Tanner, a British pediatrician, after a two-decade-long study following the physical changes in girls undergoing puberty.

Erikson's stages of psychosocial development, as articulated in the second half of the 20th century by Erik Erikson in collaboration with Joan Erikson, is a comprehensive psychoanalytic theory that identifies a series of eight stages that a healthy developing individual should pass through from infancy to late adulthood.

Gender dysphoria in children (GD), also known as gender incongruence of childhood, is a formal diagnosis for children who experience significant discontent due to a mismatch between their assigned sex and gender identity. The diagnostic label gender identity disorder in children (GIDC) was used by the Diagnostic and Statistical Manual of Mental Disorders (DSM) until it was renamed gender dysphoria in children in 2013 with the release of the DSM-5. The diagnosis was renamed to remove the stigma associated with the term disorder.

James E. Marcia is a clinical and developmental psychologist. He taught at Simon Fraser University in British Columbia, Canada and the State University of New York at Buffalo in Upstate New York.

Emerging adulthood, early adulthood, or post-adolescence refers to a phase of the life span between late adolescence and early adulthood, as initially proposed by Jeffrey Arnett in a 2000 article from the American Psychologist. It primarily describes people living in developed countries, but it is also experienced by young adults in wealthy urban families in the Global South. The term describes young adults who do not have children, do not live in their own homes, and/or do not have sufficient income to become fully independent. Arnett suggests emerging adulthood is the distinct period between 20 and 29 years of age where young adults become more independent and explore various life possibilities.

According to Alberts, Elkind, and Ginsberg the personal fable "is the corollary to the imaginary audience. Thinking of themselves as the center of attention, the adolescent comes to believe that it is because they are special and unique.” It is found during the formal operational stage in Piagetian theory, along with the imaginary audience. Feelings of invulnerability are also common. The term "personal fable" was first coined by the psychologist David Elkind in his 1967 work Egocentrism in Adolescence.

<span class="mw-page-title-main">Transgender youth</span> Children and adolescents who are transgender

Transgender youth are children or adolescents who do not identify with the sex they were assigned at birth. Because transgender youth are usually dependent on their parents for care, shelter, financial support, and other needs, they differ in challenges compared to adults. According to the World Professional Association for Transgender Health, the American Psychological Association, and the American Academy of Pediatrics, appropriate care for transgender youth may include supportive mental health care, social transition, and/or puberty blockers, which delay puberty and the development of secondary sex characteristics to allow children more time to explore their gender identity.

In psychology, maturity can be operationally defined as the level of psychological functioning one can attain, after which the level of psychological functioning no longer increases much with age. However, beyond this, integration is also an aspect of maturation, such as the integration of personality, where the behavioral patterns, motives and other traits of a person are gradually brought together, to work together effectively with little to no conflict between them, as an organized whole, e.g., bringing a person's various motives together into a purpose in life. Case in point: adult development and maturity theories include the purpose in life concept, in which maturity emphasizes a clear comprehension of life's purpose, directedness, and intentionality, which contributes to the feeling that life is meaningful.

The media and American adolescent sexuality relates to the effect the media has on the sexuality of American adolescents and the portrayal thereof.

Jeffrey Jensen Arnett is a professor in the Department of Psychology at Clark University in Massachusetts. His main research interest is in "emerging adulthood", a term he coined, which refers to the distinct phase between adolescence and young adulthood, occurring from the ages of 18 to 25.

Alcohol is a liquid form substance which contains ethyl alcohol that can cause harm and even damage to a person's DNA. "Alcohol consumption is recognized worldwide as a leading risk factor for disease, disability, and death" and is rated as the most used substance by adolescences. Adolescence is a transitional stage of physical and psychological changes, usually a time in a person life in which they go through puberty. Combining these transitional stages and the intake of alcohol can leave a number of consequences for an adolescent.

References

  1. "Adult organism". Archived from the original on 2022-11-05. Retrieved 2022-11-05.
  2. McNamara, Thomas Edward (2004). Evolution, Culture, and Consciousness: The Discovery of the Preconscious Mind. University Press of America. pp. 262–263. ISBN   0-7618-2765-X . Retrieved December 11, 2018.
  3. SETTERSTEN, RICHARD (2015). "Becoming adult: Meanings of markers to adulthood" (PDF). Emerging Trends in the Social and Behavioral Sciences: An Interdisciplinary, Searchable, and Linkable Resource: 1–16 via umnikizdes.
  4. Marantz Henig, Robin (2010-08-18). "What Is It About 20-Somethings?". The New York Times. p. 10. Archived from the original on 2011-05-11. Retrieved 2010-09-24. The Discovery of adolescence is generally dated to 1904, with the publication of the massive study "Adolescence," by G. Stanley Hall, a prominent psychologist and first president of the American Psychological Association.
  5. "Has Fecundability been Declining in Recent Years in Developed Countries?". Journal of Biosocial Science. 15 (1). January 1983. doi:10.1017/s0021932000006349. ISSN   0021-9320.
  6. Becker; Landau, Sidney I., eds. (1986). International dictionary of medicine and biology. Wiley. ISBN   0-471-01849-X. OCLC   801872498.
  7. Churchill's illustrated medical dictionary. New York: Churchill Livingstone. 1989. ISBN   0-443-08691-5. OCLC   19322374.
  8. Gluckman, Peter D.; Hanson, Mark A. (January 2006). "Evolution, development and timing of puberty". Trends in Endocrinology & Metabolism. 17 (1): 7–12. doi:10.1016/j.tem.2005.11.006. PMID   16311040. S2CID   26141301.
  9. Kail, RV; Cavanaugh JC (2010). Human Development: A Lifespan View (5th ed.). Cengage Learning. p. 296. ISBN   978-0-495-60037-4. Archived from the original on 2023-01-10. Retrieved 2018-03-20.
  10. Schuiling, Kerri Durnell; Likis, Frances E. (2016). Women's Gynecologic Health. Jones & Bartlett Learning. p. 22. ISBN   978-1-284-12501-6. Archived from the original on January 10, 2023. Retrieved March 20, 2018. The changes that occur during puberty usually happen in an ordered sequence, beginning with thelarche (breast development) at around age 10 or 11, followed by adrenarche (growth of pubic hair due to androgen stimulation), peak height velocity, and finally menarche (the onset of menses), which usually occurs around age 12 or 13.
  11. 1 2 Phillips, D. C. (2014). Encyclopedia of Educational Theory and Philosophy. SAGE Publications. pp. 18–19. ISBN   978-1-4833-6475-9. Archived from the original on January 10, 2023. Retrieved March 20, 2018. On average, the onset of puberty is about 18 months earlier for girls (usually starting around the age of 10 or 11 and lasting until they are 15 to 17) than for boys (who usually begin puberty at about the age of 11 to 12 and complete it by the age of 16 to 17, on average).
  12. Solomon, Jean W.; O'Brien, Jane Clifford (2014). Pediatric Skills for Occupational Therapy Assistants – E-Book. Elsevier Health Sciences. p. 103. ISBN   978-0-323-29163-7 . Retrieved March 20, 2018.
  13. Ge, Xiaojia; Natsuaki, Misaki N.; Neiderhiser, Jenae M.; Reiss, David (2007). "Genetic and Environmental Influences on Pubertal Timing: Results From Two National Sibling Studies". Journal of Research on Adolescence. 17 (4): 767–788. doi:10.1111/j.1532-7795.2007.00546.x.
  14. "Stages of puberty: what happens to boys and girls". nhs.uk. 2018-04-26. Archived from the original on 2020-12-04. Retrieved 2020-12-13.
  15. Henig, Robin Marantz (18 August 2010). "What is It About 20-Somethings?". The New York Times. Archived from the original on 26 February 2017. Retrieved 23 February 2017.
  16. Petanjek, Zdravko; Judaš, Miloš; Šimić, Goran; Rašin, Mladen Roko; Uylings, Harry B. M.; Rakic, Pasko; Kostović, Ivica (2011). "Extraordinary neoteny of synaptic spines in the human prefrontal cortex". Proceedings of the National Academy of Sciences. 108 (32): 13281–13286. Bibcode:2011PNAS..10813281P. doi: 10.1073/pnas.1105108108 . PMC   3156171 . PMID   21788513.
  17. "People don't become 'adults' until their 30s, say scientists". BBC News. 19 March 2019. Archived from the original on 14 June 2022. Retrieved 14 June 2022.
  18. Romer, Daniel (2010). "Adolescent risk taking, impulsivity, and brain development: implications for prevention". Developmental Psychobiology. 52 (3): 263–276. doi:10.1002/dev.20442. PMC   3445337 . PMID   20175097.
  19. Casey, BJ; Caudle, Kristina (2013). "The Teenage Brain: Self Control". Current Directions in Psychological Science. 22 (2): 82–87. doi:10.1177/0963721413480170. PMC   4182916 . PMID   25284961.
  20. Epstein, Robert (2007-06-01). "The Myth of the Teen Brain". Scientific American. Archived from the original on 2021-12-13. Retrieved 2021-12-07.
  21. Moshman, David (2011). Adolescent Rationality and Development. Psychology Press. doi:10.4324/9780203835111. ISBN   978-0-203-83511-1. Archived from the original on 2021-12-07. Retrieved 2021-12-07.
  22. Hamilton, Vivian (2016). Adulthood in Law and Culture. College of William & Mary Law School: Faculty Publications. pp. 55–97.
  23. Spooner, Samantha (July 14, 2014). "Legal ages of marriage across Africa: Even when it's 18, they are married off at 12!". Mail & Guardian Africa. Archived from the original on January 24, 2018.
  24. Bellemare, Steven (July 2008). "Age of consent for sexual activity in Canada". Paediatrics & Child Health. 13 (6): 475. doi: 10.1093/pch/13.6.475 . PMC   2532909 . PMID   19436429.
  25. B. A., Political Science. "What Does Age of Majority Mean in Canada?". ThoughtCo. Archived from the original on 2021-01-08. Retrieved 2020-12-13.
  26. "Age of Majority by State as of 2020". Policygenius. Archived from the original on 2020-12-07. Retrieved 2020-12-13.
  27. Birnbaum, Gemma R. (28 October 2020). ""Old Enough to Fight, Old Enough to Vote": The WWII Roots of the 26th Amendment". Archived from the original on 2021-06-13. Retrieved 2021-06-13.
  28. "Statute 82 Page 1213-2 PDF file" (PDF). Archived (PDF) from the original on 2021-05-15. Retrieved 2021-06-13.[ full citation needed ]
  29. "The 1984 National Minimum Drinking Age Act | APIS - Alcohol Policy Information System". alcoholpolicy.niaaa.nih.gov. Archived from the original on 2021-06-13. Retrieved 2021-06-13.
  30. DeMatteo, Megan (22 July 2020). "My first unsecured credit card came with a $20,000 limit—here's why that is rare today". CNBC. Archived from the original on 13 June 2021. Retrieved 13 June 2021.
  31. "Young Adults and the Affordable Care Act: Protecting Young Adults and Eliminating Burdens on Families and Businesses | CMS". Archived from the original on 2021-06-13. Retrieved 2021-06-13.
  32. "Tobacco 21". FDA. 22 February 2021. Archived from the original on 22 June 2021. Retrieved 13 June 2021.
  33. "What is the Age Limit of Medical Cannabis in California?". 18 September 2018. Archived from the original on 13 June 2021. Retrieved 13 June 2021.
  34. Lindeman, Tracey (30 October 2019). "Quebec raises legal consumption age for cannabis to 21". The Guardian . Archived from the original on 24 May 2021. Retrieved 13 June 2021.
  35. "Mandatory life without parole prohibited for young WA adults" . 11 March 2021. Archived from the original on 13 June 2021. Retrieved 13 June 2021.
  36. Michaels, Andrew (9 June 2016). "A Decent Proposal: Exempting Eighteen- to Twenty-Year-Olds from the Death Penalty". Archived from the original on 13 June 2021. Retrieved 13 June 2021.
  37. "Kentucky Trial Judge Rules Death Penalty Unconstitutional for Offenders Younger Than Age 21". Archived from the original on 2021-06-13. Retrieved 2021-06-13.
  38. "Should 18- to 21-year-olds be eligible for execution?". 19 September 2019. Archived from the original on 2021-06-13. Retrieved 2021-06-13.
  39. "Texas bill aims to crack down on human trafficking". 29 April 2021. Archived from the original on 13 June 2021. Retrieved 13 June 2021.
  40. "Raise age for sale of cigarettes to 21 and stop 'tobacco epidemic', say UK MPS". The Guardian . 9 June 2021. Archived from the original on 13 June 2021. Retrieved 13 June 2021.
  41. Arain, Mariam; Haque, Maliha; Johal, Lina; Mathur, Puja; Nel, Wynand; Rais, Afsha; Sandhu, Ranbir; Sharma, Sushil (2013). "Maturation of the adolescent brain". Neuropsychiatric Disease and Treatment. 9: 449–461. doi: 10.2147/NDT.S39776 . PMC   3621648 . PMID   23579318.
  42. "age of majority". LII / Legal Information Institute. Retrieved 2023-11-03.
  43. Niel, Clara (October 2020). "Takoma Park is one of five cities where minors can vote. And young voters are turning out". Archived from the original on 2021-05-10. Retrieved 2021-06-13.
  44. Settersten, Richard A. Jr. (2 December 2018). Lives in time and place: the problems and promises of developmental science. Taylor & Francis. ISBN   978-0-415-78421-4. OCLC   1121019775.[ page needed ]
  45. Elder, Glen H., ed. (1985). "Perspectives on the life course". Life course dynamics: trajectories and transitions, 1968-1980. Cornell University Press. pp. 23–49. ISBN   0-8014-9323-4. OCLC   469306035.
  46. Ryff, Carol D. (16 January 2018). "The Subjective Experience of Life-Span Transitions". In Rossi, Alice S. (ed.). Gender and the life course. Routledge. pp. 97–113. ISBN   978-1-351-32902-6. OCLC   1028167964.
  47. Arnett, Jeffrey Jensen (1998). "Learning to Stand Alone: The Contemporary American Transition to Adulthood in Cultural and Historical Context". Human Development. 41 (5/6): 295–315. doi:10.1159/000022591. JSTOR   26763368. S2CID   143862036.
  48. Levinson, Daniel J. (1979). The Seasons of a man's life. Ballantine Books. ISBN   0-345-29727-X. OCLC   9162079.
  49. Shanahan, Michael J. (August 2000). "Pathways to Adulthood in Changing Societies: Variability and Mechanisms in Life Course Perspective". Annual Review of Sociology. 26 (1): 667–692. doi:10.1146/annurev.soc.26.1.667. JSTOR   223461.
  50. Arnett, Jeffrey Jensen (2003). "Conceptions of the Transition to Adulthood Among Emerging Adults in American Ethnic Groups". New Directions for Child and Adolescent Development. 2003 (100): 63–76. doi:10.1002/cd.75. PMID   12955983.
  51. 1 2 Aronson, Pamela (February 2008). "The Markers and Meanings of Growing Up: Contemporary Young Women's Transition From Adolescence to Adulthood". Gender & Society. 22 (1): 56–82. doi:10.1177/0891243207311420. PMC   2312095 . PMID   18418470.
  52. Barrett, Anne E. (March 2003). "Socioeconomic Status and Age Identity: The Role of Dimensions of Health in the Subjective Construction of Age". The Journals of Gerontology Series B: Psychological Sciences and Social Sciences. 58 (2): S101–S109. doi: 10.1093/geronb/58.2.s101 . PMID   12646599.
  53. Barrett, Anne E. (May 2005). "Gendered experiences in midlife: Implications for age identity". Journal of Aging Studies. 19 (2): 163–183. doi:10.1016/j.jaging.2004.05.002.
  54. Settersten, Richard A. Jr.; Furstenberg, Frank F.; Rumbaut, Rubén G., eds. (15 April 2008). "On the Frontier of Adulthood: Emerging Themes and New Directions". On the frontier of adulthood: theory, research, and public policy. University of Chicago Press. pp. 3–25. ISBN   978-0-226-74890-0. OCLC   191752480.
  55. Shanahan, Michael J.; Porfeli, Erik J.; Mortimer, Jeylan T.; Erickson, Lance D. (15 April 2008). "Subjective Age Identity and the Transition to Adulthood: When do Adolescents Become Adults?". In Settersten, Richard A. Jr.; Furstenberg, Frank F.; Rumbaut, Rubén G. (eds.). On the frontier of adulthood: theory, research, and public policy. University of Chicago Press. pp. 225–255. ISBN   978-0-226-74890-0. OCLC   191752480.
  56. Arnett, Jeffrey Jensen (2014). Emerging adulthood: the winding road from the late teens through the twenties. Oxford University Press. ISBN   978-0-19-992938-2. OCLC   945977734.[ page needed ]
  57. Waters, Mary C.; Carr, Patrick J.; Kefalas, Maria J.; Holdaway, Jennifer (15 April 2008). "Becoming Adult: Meanings and Markers for Young Americans". In Settersten, Richard A. Jr.; Furstenberg, Frank F.; Rumbaut, Rubén G. (eds.). On the frontier of adulthood: theory, research, and public policy. University of Chicago Press. pp. 169–190. ISBN   978-0-226-74890-0. OCLC   191752480.
  58. "Jeffrey Jensen Arnett, PhD". apa.org. Archived from the original on 2020-11-02. Retrieved 2020-12-13.
  59. 1 2 3 Munsey, Christopher (June 2006). "Emerging adults: The in-between age". Monitor on Psychology. Vol. 37. American Psychological Association. p. 68. Retrieved 2020-12-13.
  60. Arnett, Jeffrey Jensen (December 2007). "Emerging Adulthood: What Is It, and What Is It Good For?". Child Development Perspectives. 1 (2): 68–73. doi:10.1111/j.1750-8606.2007.00016.x. ISSN   1750-8592.
  61. "Bar Mitzva in Peninei Halakha by rabbi Eliezer Melamed". Archived from the original on 2022-10-18. Retrieved 2022-10-18.
  62. "Bat Mitzva in Peninei Halakha by rabbi Eliezer Melamed". Archived from the original on 2022-10-18. Retrieved 2022-10-18.
  63. "Code of Canon Law: Table of Contents". vatican.va. Archived from the original on 2021-08-22. Retrieved 2022-12-23.
  64. Donelson, Elaine (1999). "Psychology of religion and adolescents in the United States: Past to present". Journal of Adolescence. 22 (2): 187–204. doi:10.1006/jado.1999.0212. PMID   10089119.
  65. Lee, Bo Hyeong Jane; Pearce, Lisa D.; Schorpp, Kristen M. (September 2017). "Religious Pathways from Adolescence to Adulthood". Journal for the Scientific Study of Religion. 56 (3): 678–689. doi:10.1111/jssr.12367. PMC   5912683 . PMID   29706663.