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Healthy teenagers can go through puberty at different ages -

On average, girls begin puberty at 11 while boys typically start at 12, though girls can start as early as 8 or 9, or as late as 13, and boys can start as early as 9 or as late as 13 as well. 

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Puberty age has dropped over the years -

At the turn of the century, the average American girl wouldn’t get her period until she was around 16-17, whereas now, girls are going through this on average at 12-13.

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Puberty age has dropped over the years -

There are many theories that explain this, including the exposure to synthetic chemicals, higher levels of stress and obesity.

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Puberty age has dropped over the years -

Some point to poor nutrition and higher rates of disease as the cause of later puberty in the past.

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Risks of early puberty -

Precocious puberty can affect individuals later in life. Girls are at higher risk of developing breast and ovarian cancer, as well as obesity.

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Risks of early puberty -

Early puberty is also correlated with psycho-social issues, including higher likelihood of developing depression and substance abuse.

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Voice change -

Boys’ voices change when they reach puberty. It gets lower and deeper. This is due to a number of physiological changes.

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Anatomical changes -

An increase in testosterone levels causes the cartilage and vocal cords to grow, and the larynx also shifts (the Adam's apple becomes visible).

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Castrati -

Except for the Castrati: a group of young boys who sang in church choirs. This is because they were castrated before puberty to maintain their high-pitch voices.

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Castrati -

The Italian castrato singer, Alessandro Moreschi was reportedly the only castrato to record solo.

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Guevedoces -

There’s a small community in the Dominican Republic where a number of children are born with female features, but then develop male genitalia during puberty. 

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Guevedoces -

This is due to a genetic condition. The delay in developing male genitalia is due to a deficiency in an enzyme called 5-alpha-reductase, which converts testosterone into dihydro-testosterone. This process usually happens in the womb.

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Lefties reach puberty slightly later than right-handed children -

This might potentially be related to lefties’ slightly smaller stature on average, but more research is needed.

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Acne -

Acne usually appears during puberty. Androgens—hormones that are present during adolescence—will trigger the sebaceous glands, which can lead to clogging of the pores and feeding of acne bacteria. 

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Blackheads -

The medical term for blackheads is comedo, which comes from the Latin word for glutton. Nineteenth-century doctors would use the term to describe parasitic worms, which resembled blackheads.

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Male and female brains develop differently during puberty -

Scans have found that boys show an increase in connectivity in certain brain areas, while girls show a decrease in connectivity in the same areas of the brain.

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Male and female brains develop differently during puberty -

Dr. Jaanus Harro, from the Division of Neuropsychopharmacology at the University of Tartu says: "This is particularly interesting in terms of demonstrating connectivity differences between boys and girls. While depression is more prevalent in females it still does occur in males too frequently, while the formal diagnostic criteria are identical."

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Male and female brains develop differently during puberty -

Dr. Harro added: “However, the neural pathways to depression in males and females might be partly different, as increasing number of gene-environment interaction studies has shown different interactions in boys and girls, on occasion quite opposite to one other. This imaging study offers a potential brain correlate to these distinct interactions, and it is quite plausible that they might arise during adolescence."

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Some animals take a lot longer than humans to reach sexual maturity -

Greenland sharks for instance, take their time. Around 150 years for females, to be more precise, which, considering that they live an average of 300–500 years, is not that long.

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Some animals never reach puberty -

Aphids don’t have to reach sexual maturation to reproduce. They are essentially born pregnant!

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Dog teenage angst -

Yes, dogs also struggle with obedience during adolescence. As with human teens, dogs also rebel against their parents (in this case, owners) but respond more positively to external figures of authority.

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Cows -

Cows’ behavior is also less predictable while going through puberty, according to a study. Yes, teen cows also get moooody.

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Cabrera's hutia -

These rodents reach puberty according to weight, rather than age. Around 360 g for females, and 300 g for males.

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Birds -

Some birds grow spectacular plumage during puberty. This has different functions, according to species, but it’s mostly for attracting mates.

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Birds -

But it’s not always male birds that grow exuberant plumage for mating. Some birds, such as Sandpipers and Buttonquail, have reverse sexual roles.

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Birds -

Males incubate eggs and females defend their territory, and fight for male attention. In this case, females have the most beautiful plumage.

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Even seemingly basic plumage can be attractive -

Birds have four types of cone cells in their eyes (humans only have three) so it’s believed that they see color and light differently. For instance, they can see UV light.

Sources: The Royal Society, Science Daily)

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See also: -

Weird and wonderful facts about your body

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