Thursday, April 2, 2009

What Apes Can Teach Us Pt II

My original question (in my last post, What Apes Can Teach Us) was whether a baby would take longer to develop the ability to sit up, crawl and walk if left to its own devices; that is, if it was looked after, but not encouraged to reach the next goal by being sat upright, placed on its stomach or put in a baby walker. As I said in the last post, it is probably impossible to answer this question without conducting unethical and unpalatable trials on identical twins. But I wondered if a likely answer might be obtained by observing the parenting strategies of our closest cousins in the animal kingdom, the great apes. Actually I'm not sure I have got any further with the original question but a cursory bit of research on orangutans, gorillas and chimpanzees did yield some fascinating truths about how they bring up their babies - and perhaps how ours should be raised. In particular, I looked at nursing, weaning, baby carrying and sleeping habits. I will cover each in turn but first I think it is necessary to establish whether it is valid to assume that without the influence of society, the behaviour of a human towards its child would resemble that of an ape towards its offspring. Here is my view: a human is a very similar organism to a gorilla, a chimpanzee or an orangutan. Presumably, evolution has ensured that an adult ape instinctively behaves in such a way that its baby has the best possible chance of survival. Since our physiology is so similar, human babies have very similar basic needs to great ape babies. So it seems reasonable to assume that the "optimal" behaviour for a great ape parent would be similar to the "optimal" behaviour for a human parent. No, not identical, but there is surely enough similarity that we can at least think about what apes do, and use it to inform what might be best for our babies. Of course it should be instinctive for humans to behave optimally when raising their children, but unfortunately our minds are clouded with memories of our own upbringing, well-meant advice and so-called expert guidance. Even if we behave in a natural, instinctive way (such as taking our babies to bed) we often feel like we are doing something wrong. Anyway, on to the topics mentioned above.


Katherine Dettwyler wrote a PhD dissertation on the natural length of time for humans to nurse, by studying nursing in great apes. She used a variety of methods to scale up the ape nursing periods; this yielded various periods of human nursing from 2.5 years to 7 years. My brief research showed that great apes nurse for around 3-4 years. So it would seem that "extended nursing" in humans is really normal nursing for our species.

Weaning on to solid food

Great apes begin eating bits of vegetation or fruit, as appropriate for their diet, at around 3 months of age. This is not really that different to human babies - Cave Baby certainly started grabbing food out of my hands at about that age. Whilst I presume that most of the eating that infant apes do is "baby-led", ie they pick it up themselves and put it in their own mouths, I have read that orangutans sometimes chew up some fruit before giving it to their babies. This would seem to provide some justification for the human practice of mashing foods. Perhaps the most "natural" weaning route for humans to take is a mixture of mashed and finger foods, right from the beginnig of weaning, with babies primarily self-feeding.

Baby Carrying

Apes have an advantage when carrying their babies - they have fur, and the babies quickly become strong enough to hold on to the fur. They carry the babies on their fronts constantly for several months (around 6 or more), and when the babies become too heavy, they move to their parents' backs. Since apes use their fur both to keep warm and to carry their young, it makes some sense that humans would make clothes both to insulate them and to carry young. So, without the benefit of fur, perhaps carrying babies in slings is the most natural thing for a human mother to do.


Sleeping with young is so natural and instinctive that it scarcely needs any more explanation; but great apes do indeed sleep with their children for a number of years. It seems from the reading I did that shared sleeping lasts until nursing finishes; perhaps this is a guide as to when human co-sleeping should end - with the end of nursing comes independence and the beginning of a "juvenile" rather than "infant" period of life.

I do not wish this to read like a recipe for how anybody should be bringing up their children. Humans are successful partly because we have society and culture, so societal norms themselves may grant us some advantage that improves survival. But anyone who has chosen to follow their own parental instincts, perhaps baby-wearing or co-sleeping, may recognise a lot of their methods in those used by orangutans, gorillas and chimpanzees.

Oh, and to answer my original question - apes are carried almost constantly until they can walk, so I reckon human babies would still learn to crawl and walk without hot housing.


Mon said...

What a great post!

I'm not buying it, this whole 'apes are enough like us to use them to make claims about human behaviours', but great post anyway! I enjoyed reading it.

Earthenwitch said...

I too wonder about timing of various developmental milestones. Several people have suggested that the witchling would have rolled over sooner (she only really started to do it at about eight months) if we hadn't carried her for so much time in the average day, but the flip-side, I think, is that she has very good upper-body control, and has had for a long time, which I attribute to having ridden around on us all the time!

As for whether or not putting babies on their tums and all that makes a difference, I don't know. I have a friend whose baby has spent a lot of time sitting on his own on the floor, and he is extraordinarily mobile compared with the witchling, but he cries a lot and I wonder if he would be a happier, albeit a stiller, baby if he just got picked up a bit more.

Cave Mother said...

There was some interesting stuff in "Three in a Bed" by Deborah Jackson about children developing at different rates depending on how they were raised. Carried babies might develop physical skills more slowly but be more advanced verbally. What is "normal" development in the West might be quite different elsewhere. And Earthenwitch, I agree that fast isn't necessarily better. Maybe it's better to be held more, feel happy, develop emotionally, not worry too much about how soon they walk. Cave Baby can't roll much and every other babe I know at the same age can. But she sure loves being carried around the house, joining in with vacuuming, cooking etc, and I bet the other babes don't get to do that.

Earthenwitch said...

Quite. The witchling is more than happy to help with washing-up, or cooking, or putting washing away; she's no trouble at all in that sort of situation. I tend to think that it's just not worth her getting upset about things - if we don't get the washing put away, it's not the end of the world, but if she's crying for yonks, that's really not good - no laundry is worth that! I guess it's all balance, isn't it? And trying to avoid comparisons with other babies when you know parents have radically different approaches...

Earthenwitch said...

Oh, and I liked 'Three in a Bed'. Have you read Naomi Stadlen?

Cave Mother said...

No but I want to read more stuff like that so I'll have a look. Thanks. PS I haven't heard/read anyone say "Yonks" for, literally, yonks, so that made me smile and I shall try to use it today :-).