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I watched a tv show about orangutans last night and learned that although the adults prefer a solitary life, their babies are nursed for 4-6 years and stay with their mum for a few more years after that. It is believed that this extended period of childhood helps them become independent and able to survive on their own later. This fascinated me because I have often been questioned about our practices of extended breastfeeding, babywearing & cosleeping, with people expressing concerns that littlepixie will grow up clingy. Not at all, I tell them, it'll make her more secure and confident.  I found more information here on orangutans
By age four, orangutan juveniles are usually weaned, though they may still nurse during periods of stress until they are seven years old. As I watched the little orangutans on the tv last night, being carried on their mother's back, I thought how similar we are to them, and wondered about the rest of the Great Apes…  Gorillas nurse their young for 3-4 years.
The juvenile period is from three to six years and is characterized by a decrease in maternal grooming, no longer sharing a sleeping nest with the mother, and weaning. Because of the enormity of the task of rearing infants and the stress of lactation on the mother's body, female gorillas experience lactational amenorrhea until the infant is weaned at three or four years. Chimpanzees nurse for 4-6 years. Not until three years of age do young chimpanzees venture more than five meters from their mothers, and between ages four and six, the period of infancy ends with weaning.  Bonobos nurse for 4-5 years.
Bonobos are not weaned until four or five years of age. They are sustained by nursing for the first year of life, and though they may mouth food, they never consume it in the first year. So there you go, despite their diverse lifestyles and family groupings, our closest relatives practice "extended" breastfeeding as a part of normal life. There's one other Great Ape to consider, us, humans. When is our natural weaning age? Katherine Dettwyler has an interesting article "When to wean" where she addresses this question… Studies of nonhuman primates offer a number of different means of estimating the natural time for human weaning. First, large-bodied primates wean their offspring some months after the young have quadrupled their birth weight. In modern humans, this weight milestone is passed at about two and a half to three years of age. Second, like many other mammals, primate offspring tend to be weaned when they have attained about one third of their adult weight; humans reach this level between four and seven years of age. Third, in all species studied so far, primates also wean their offspring at the time the first permanent molars erupt; this occurs at five and a half to six years in modern humans. Fourth, in chimpanzees and gorillas, breast-feeding usually lasts about six times the duration of gestation. On this basis, a human breast-feeding would be projected to continue for four and a half years. Taken together, these and other projections suggest that somewhat more than two and a half years is the natural minimum age of weaning for humans and seven years the maximum age, well into childhood. The high end of this range, six to seven years, closely matches both the completion of human brain growth and the maturation of the child's immune system. It makes you think about how messed up our society's view of breastfeeding is, when the majority of western infants don't get more than a few days or weeks of human milk before switching to a cow, goat or soy variety. It's a bit sad really. Here a few more photos from flickr: Orangutans: Gorillas: Chimpanzees: Bonobos: Orangutan & chimpanzee photos shown above are from fotosearch.com Pixiegirl thank you for this!
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The Lighter Side 
