It seems as if I’ve had a lot of discussions of maternal depression lately-- both the perinatal mood disorders of birth mothers and post-adoption depression. When these topics come up, there are a lot of different responses. Some deny that there could be post-adoption depression, because they’re convinced that the hormones of pregnancy cause perinatal mood disorders (although if this were the case, it’s not too clear why all women don’t have the same problems). Others feel that the women are just suffering from “buyer’s remorse” and could do perfectly well if they just pulled their socks up. Still others feel that such mood disorders are excuses given by people who don’t like the hard work of early motherhood.
In most cases, people focus on the mother as the significant person, the one who’s influenced by depression. They forget the fact that the impact of maternal depression on a baby’s development can be quite negative. They also forget that this is an issue that has significance not just for mothers but for all major caregivers. Depression in nannies, day care providers, or grandmothers who “watch” the child while the mother works all have the potential for interfering with optimum development. (You notice I don’t say “normal development”. Things have to get pretty bad before development gets below the bottom of the normal range-- but long before that there may be a deviation from a baby’s best developmental trajectory, the one that will result in the best developmental outcome.)
So, what do depressed mothers and caregivers do that’s so different from what better-functioning people manage?
Imagine your own experiences with depression-- whether they involved an afternoon of low interest in life, or a long, serious problem with thoughts of suicide. Think how you feel when you’re depressed, what you feel like doing, and how you respond to other people. You’ll probably realize that you feel not only sad, but slow, tired, unresponsive, hard to please, pessimistic, and perhaps guilty or even worthless. You’d like people either to leave you alone completely or to nurture you without thought of themselves. You don’t want to talk or listen to others, you don’t want to make eye contact, you don’t smile or show expression in your posture or gestures.
Then, imagine how you feel when you’re with someone else who is depressed (and you aren’t). You may feel and act sympathetic at first, but that might not last long in the face of their negative mood. You interpret the other person’s mood as anger or hostility or rejection, and soon you respond to that perceived mood by being angry yourself. You don’t want to be with that person, and if you have to be (you live together, for instance), you may end up picking a fight just to get some acknowledgement of your existence.
Now, I don’t want to act as if I think babies have the same interpretations of other people’s behavior as adults do. I’m positive they do not. But when you consider how you feel when you’re depressed, and how you react to other depressed people, I think you can catch something of the flavor of a baby’s reaction to a depressed caregiver. In addition to that “flavor”, though, it might be good to consider some things depressed caregivers do or don’t do, and how those things relate to a baby’s needs.
1.Depressed caregivers don’t talk much.
Babies need to hear speech from the earliest months. Initially, hearing speech helps babies learn which noises adults make as part of speech, and which are not part of speech. To understand a language, you have to learn that particular sounds determine the meaning of speech, and others, like humming, coughing, or saying “ummm” do not. Different languages have different proportions of certain speech sounds and sometimes don’t use a particular sound at all. Babies who hear little speech are delayed in their understanding of the way their native language works and which sounds they need to pay attention to in order to understand.
2.Depressed caregivers make the “still face” often.
By a few months of age, certainly by 4-6 months, babies have normally learned to expect adult facial expressions to change in response to baby communications. When an adult makes the “still face”-- gazing blankly and unresponsively as if he or she can’t see the baby-- it’s very disturbing to the baby, who will begin to cry quite soon, will avert his or her gaze and become disorganized, sometimes hiccupping or spitting up. Adults can make still faces under perfectly normal situations like trying to remember where the car keys are or trying to talk to the plumber on the phone while the baby makes a bid for attention. Ordinarily, though, the non-depressed adult quickly comes back and re-engages with the baby, repairing their temporarily troubled communication. Depressed caregivers, on the contrary, may not only do the still face more often, but may lack the energy or interest to help the baby later understand that everything is okay and resolve the disorganization and anxiety the baby feels.
3.Depressed caregivers do only the basics.
Fatigue and slowing of responses are part of depression and interfere with normal infant care routines. Ordinarily, caregivers do a lot more than just the physical jobs of caring for a baby. The non-depressed caregiver who is changing a diaper talks to the baby in an interesting, voice that catches the baby’s attention. She plays with the baby at the same time, making eye contact, smiling, tickling or blowing on the tummy, perhaps giving the baby a toy to hold (not entirely play, of course, this is a good strategy for keeping the little hands out of the dirty diaper). When feeding the baby, she talks and jokes, perhaps pretending to eat some of the food herself (for some reason, this is a wow with the high-chair set), or helping the baby pick up some finger food. The depressed caregiver goes through these routines without any of the usual grace notes, doing the minimum and missing out the actions that pique the baby’s interest and foster communication, as well as those that encourage learning.
4.Depressed caregivers may not be very careful or attentive.
When babies can roll over, or pull to stand in their cribs, or later on crawl and so on, caregivers need “eyes in the back of their heads” to ensure safety. Even so, most babies experience a few scary tumbles as their caregivers fail to anticipate their doing something for the first time. The depressed caregiver moves slowly and has trouble paying attention to more than the troubles in her own thoughts and feelings. She may be so preoccupied that the baby might as well be at the top of the stairs or in the bathtub alone. Paradoxically, the depressed caregiver’s sense of guilt or worthlessness may concern her so much that she fails to prevent accidents and thus really does become guilty.
These are only a few of the caregiving problems that can be associated with depression. It may well be that the best thing we could do to foster good early development would be to attend to and treat the depression of mothers and other infant caregivers, so they can do the optimum job of bringing up young children.
Tuesday, April 19, 2011
Sunday, April 10, 2011
Breastfeeding: Test Your Knowledge-- True or False?
The important human function of breastfeeding is the subject of many myths and misunderstandings. A fascinating meld of biological and behavioral events, it’s worth the attention of everyone interested in early development, even those who will not be participating at the adult end. Test your knowledge of breastfeeding by reading these “true or false?” questions.
1. Breastfeeding helps the baby resist infectious diseases. True or false?
Very true! Although babies are born with a supply of antibodies they got from their mothers’ immune systems, those antibodies can only protect against diseases the mother had already been exposed to, not exposure to new diseases after the birth. In addition, those antibodies will have diminished by the time the baby is about 8 months old, a point at which infants do not yet do a good job of making their own antibodies. The nursing mother acts as an “auxiliary immune system” to her infant. She supplies more of the antibodies she already had, and if the nursing pair are exposed to a new disease, the mother’s efficient immune system goes to work to produce antibodies and pass them on to the baby in her milk. What if the baby is exposed to something, and the mother not exposed to it? Don’t worry, she will be exposed quickly, because the physical intimacy of nursing (and other infant care) means she will come into contact with the baby’s mucus, urine, and feces.
Do note that the baby can still use this kind of help toward the end of the first year. Babies who live in clean conditions, with modern food supplies and access to modern medicine, are less affected by a lack of breastfeeding, but those living in primitive conditions may die of infections that could have been prevented by breastfeeding.
2.Nursing mothers need to eat a lot more than usual. True or false?
It depends on the conditions. If the mother was well nourished during the pregnancy, she has laid down extra fat and extra calcium in her bones, and these will be used to support lactation, so she needs little if any extra food. If the mother is living at a subsistence level, she will need extra calories to compensate for those consumed by the baby. An ounce of human milk has about 20 calories on the average, so you can do the math, considering the amount of milk consumed by babies of different sizes and ages.
The nursing mother does need to drink a lot more fluid than when she is not breastfeeding. Every ounce of fluid the baby takes needs to be replaced. Many nursing mothers automatically go to drink a glass of water before they pick up the baby to nurse, or have a cup of tea while breastfeeding. Traditionally, nursing mothers drank dark beers like porter, which supplied extra fluid and a hefty dose of B vitamins, and gave everyone a nice nap too-- nowadays we tend to frown on this, and certainly this practice would have its dangers if it occurred more than once in a while .
3. You can’t breastfeed a baby once he or she gets teeth. True or false?
False. Babies can easily be taught not to bite the nipple, if the mother is vigilant (and believe me, after one bite she WILL be vigilant). Biting and sucking take different jaw movements, and an attentive mother can see when a sucking baby re-adjusts its jaw position in preparation for a chomp. The mother then gently inserts her finger between the baby’s jaws, toward the back of the mouth. This breaks the suction, so the baby cannot get any milk, and if he or she bites down, there’s not much satisfaction, because those itchy teething gums are in the front. Within 24 hours, the baby will have learned that although you can bite lots of things, you can’t bite that nipple-- it just doesn’t work.
Nursing mothers really have to teach biting babies not to bite, or their nipples can actually be damaged, and the baby will have to be weaned from the breast.
4. Nursing babies don’t like the milk that’s flavored by strong-tasting foods their mothers have eaten. True or false?
This is mainly false, with some possible individual exceptions. The taste researchers Menella and Beauchamp fed a group of nursing mothers an all-garlic-flavored lunch, waited a couple of hours, and then timed how long the babies nursed. When they compared this to nursing time after a bland lunch, they found that the babies actually nursed longer when the milk had a garlic flavor.
There may be some individual differences, with particular babies possibly disliking certain flavors. One important point is that when a nursing mother has had a mild breast infection, the milk on that side seems to be a little saltier than usual, and babies may not care for it-- to the mother’s frustration, as frequent thorough nursing is a help in clearing up these problems.
1. Breastfeeding helps the baby resist infectious diseases. True or false?
Very true! Although babies are born with a supply of antibodies they got from their mothers’ immune systems, those antibodies can only protect against diseases the mother had already been exposed to, not exposure to new diseases after the birth. In addition, those antibodies will have diminished by the time the baby is about 8 months old, a point at which infants do not yet do a good job of making their own antibodies. The nursing mother acts as an “auxiliary immune system” to her infant. She supplies more of the antibodies she already had, and if the nursing pair are exposed to a new disease, the mother’s efficient immune system goes to work to produce antibodies and pass them on to the baby in her milk. What if the baby is exposed to something, and the mother not exposed to it? Don’t worry, she will be exposed quickly, because the physical intimacy of nursing (and other infant care) means she will come into contact with the baby’s mucus, urine, and feces.
Do note that the baby can still use this kind of help toward the end of the first year. Babies who live in clean conditions, with modern food supplies and access to modern medicine, are less affected by a lack of breastfeeding, but those living in primitive conditions may die of infections that could have been prevented by breastfeeding.
2.Nursing mothers need to eat a lot more than usual. True or false?
It depends on the conditions. If the mother was well nourished during the pregnancy, she has laid down extra fat and extra calcium in her bones, and these will be used to support lactation, so she needs little if any extra food. If the mother is living at a subsistence level, she will need extra calories to compensate for those consumed by the baby. An ounce of human milk has about 20 calories on the average, so you can do the math, considering the amount of milk consumed by babies of different sizes and ages.
The nursing mother does need to drink a lot more fluid than when she is not breastfeeding. Every ounce of fluid the baby takes needs to be replaced. Many nursing mothers automatically go to drink a glass of water before they pick up the baby to nurse, or have a cup of tea while breastfeeding. Traditionally, nursing mothers drank dark beers like porter, which supplied extra fluid and a hefty dose of B vitamins, and gave everyone a nice nap too-- nowadays we tend to frown on this, and certainly this practice would have its dangers if it occurred more than once in a while .
3. You can’t breastfeed a baby once he or she gets teeth. True or false?
False. Babies can easily be taught not to bite the nipple, if the mother is vigilant (and believe me, after one bite she WILL be vigilant). Biting and sucking take different jaw movements, and an attentive mother can see when a sucking baby re-adjusts its jaw position in preparation for a chomp. The mother then gently inserts her finger between the baby’s jaws, toward the back of the mouth. This breaks the suction, so the baby cannot get any milk, and if he or she bites down, there’s not much satisfaction, because those itchy teething gums are in the front. Within 24 hours, the baby will have learned that although you can bite lots of things, you can’t bite that nipple-- it just doesn’t work.
Nursing mothers really have to teach biting babies not to bite, or their nipples can actually be damaged, and the baby will have to be weaned from the breast.
4. Nursing babies don’t like the milk that’s flavored by strong-tasting foods their mothers have eaten. True or false?
This is mainly false, with some possible individual exceptions. The taste researchers Menella and Beauchamp fed a group of nursing mothers an all-garlic-flavored lunch, waited a couple of hours, and then timed how long the babies nursed. When they compared this to nursing time after a bland lunch, they found that the babies actually nursed longer when the milk had a garlic flavor.
There may be some individual differences, with particular babies possibly disliking certain flavors. One important point is that when a nursing mother has had a mild breast infection, the milk on that side seems to be a little saltier than usual, and babies may not care for it-- to the mother’s frustration, as frequent thorough nursing is a help in clearing up these problems.
Tuesday, April 5, 2011
A Survivor of Holding Therapy Tells His Story
Please go to http://anyachaika.wordpress.com/2011.04/05/a-first-hand-account-of-holding-therapy-in-the-uk and read one boy's experience of holding therapy and other disturbing treatment. The author of this piece is a young man now and is preparing to fight against the use of "fringe" mental health treatments in the United Kingdom.
Saturday, April 2, 2011
Rats and Mice and Such Small Deer: Can They Help Us Learn About Human Infants?
Over at http://marginalperspectives.blogspot.com there’s a discussion going on about research on other species. Reference has been made to a research article: Graham,Y.P., Heim, C., Goodman,S.H., Miller, A.H., & Nemeroff,C.B. (1999). The effects of neonatal stress on brain development: Implications for psychopathology. Development and Psychopathology, 11, 545-565. (And yes, if that name rings a bell, this is the same Nemeroff who had to leave Emory because of failure to report his income from a drug company--- http://www.emorywheel.com/detail.php?n=27732). At marginalperspectives, people are talking about whether information obtained by observing rats can be generalized to human infants. They’re most concerned about the effects of separation from the mother, as evidenced by rat experiments (I mean experiments using rats as subjects, not experiments performed by rats).
The Graham et al paper reports, among many other things, that undesirable brain changes occur in young rats who are separated from their mothers, even though in one situation somewhat older pups could see the mothers through a transparent burrow. The marginalperspectives group suggest that this means that similar effects occur in human babies who are separated from their mothers, as, for example, in a hospital nursery, or of course in adoption.
The Graham group notes the large developmental differences between the central nervous system maturity of newborn rats and humans, noting that a human at 24 weeks gestational age (still 16 weeks preterm) is equivalent in maturity to a newborn rat pup. This in itself points up for us differences between the species. In addition, though, we need to look at differences in rat and human experience of separation. When rat pups are experimentally removed from their mothers in this kind of study, they are NOT given substitute maternal care. Separation from the mother means separation from care. When human infants are separated from their birthmothers in medical situations or in adoption and fostering, they are given substitute care. The only parallel involving substitute care for rats lies in the situation described by Graham et al, in which additional handling by human beings is beneficial for rat pups’ brain and behavioral development.
The Graham article does not allow easy generalization of these points from rat pups to human infants. To try to do this is to confound the variables of maternal-like care and of the mother herself. We can’t logically jump from the experiences of rat pups in experimental separation to those of human infants who are fostered or adopted, nannied, nursed, baby-sat, or picked up by their daddies or big brothers or sisters.
Let me point out, by the way, that not only are humans developmentally and neurologically different from rats, and that rat pups are more mature than humans at birth-- rat mothers also behave differently from human mothers. As an old-fashioned psychologist, dating back to the days when every psych student worked with pigeons or rats or both as part of their studies, I know a lot about this (including how to pick the little guys up without getting bitten).
Rat mothers have much different jobs from human mothers/caregivers. It doesn’t matter if they’re depressed or anxious, because they needn’t talk or communicate with gestures like eye movement. They don’t need to pick up a baby and help it latch on to the nipple, or to maintain their marital relationships during the trying first months of motherhood. Here’s what they do: if a baby gets out of the nest, they retrieve it and put it back in so it doesn’t get cold. They lick the babies all over, thus stimulating urination and defecation, and you guessed it, they lick that up too. If a baby is very sick or dies, they eat it (and of course they started their maternal care by eating off the amniotic sacs and placenta, occasionally eating a baby while they were at it). When the babies start to grow fur, the mother gets a lot less interested. (By the way, the pups at birth are just pink bare skin, so transparent that you can actually see the milk in their stomachs after they nurse-- a sight that would probably be comforting to worried nursing mothers if humans had it too!)
Studying other species can give us some good ideas about how humans might develop, but until we test the ideas in humans themselves, we can’t safely conclude that the facts about one species tell us the facts about another. Does anyone remember Thalidomide, the tranquilizer that caused severe birth defects in Europe? It was thoroughly tested with animal models. It wasn’t teratogenic in those cases. But it surely was in humans. It was a bad idea to generalize too quickly across species about that drug, and that should tell us something about generalizing across species about social and emotional development.
The Graham et al paper reports, among many other things, that undesirable brain changes occur in young rats who are separated from their mothers, even though in one situation somewhat older pups could see the mothers through a transparent burrow. The marginalperspectives group suggest that this means that similar effects occur in human babies who are separated from their mothers, as, for example, in a hospital nursery, or of course in adoption.
The Graham group notes the large developmental differences between the central nervous system maturity of newborn rats and humans, noting that a human at 24 weeks gestational age (still 16 weeks preterm) is equivalent in maturity to a newborn rat pup. This in itself points up for us differences between the species. In addition, though, we need to look at differences in rat and human experience of separation. When rat pups are experimentally removed from their mothers in this kind of study, they are NOT given substitute maternal care. Separation from the mother means separation from care. When human infants are separated from their birthmothers in medical situations or in adoption and fostering, they are given substitute care. The only parallel involving substitute care for rats lies in the situation described by Graham et al, in which additional handling by human beings is beneficial for rat pups’ brain and behavioral development.
The Graham article does not allow easy generalization of these points from rat pups to human infants. To try to do this is to confound the variables of maternal-like care and of the mother herself. We can’t logically jump from the experiences of rat pups in experimental separation to those of human infants who are fostered or adopted, nannied, nursed, baby-sat, or picked up by their daddies or big brothers or sisters.
Let me point out, by the way, that not only are humans developmentally and neurologically different from rats, and that rat pups are more mature than humans at birth-- rat mothers also behave differently from human mothers. As an old-fashioned psychologist, dating back to the days when every psych student worked with pigeons or rats or both as part of their studies, I know a lot about this (including how to pick the little guys up without getting bitten).
Rat mothers have much different jobs from human mothers/caregivers. It doesn’t matter if they’re depressed or anxious, because they needn’t talk or communicate with gestures like eye movement. They don’t need to pick up a baby and help it latch on to the nipple, or to maintain their marital relationships during the trying first months of motherhood. Here’s what they do: if a baby gets out of the nest, they retrieve it and put it back in so it doesn’t get cold. They lick the babies all over, thus stimulating urination and defecation, and you guessed it, they lick that up too. If a baby is very sick or dies, they eat it (and of course they started their maternal care by eating off the amniotic sacs and placenta, occasionally eating a baby while they were at it). When the babies start to grow fur, the mother gets a lot less interested. (By the way, the pups at birth are just pink bare skin, so transparent that you can actually see the milk in their stomachs after they nurse-- a sight that would probably be comforting to worried nursing mothers if humans had it too!)
Studying other species can give us some good ideas about how humans might develop, but until we test the ideas in humans themselves, we can’t safely conclude that the facts about one species tell us the facts about another. Does anyone remember Thalidomide, the tranquilizer that caused severe birth defects in Europe? It was thoroughly tested with animal models. It wasn’t teratogenic in those cases. But it surely was in humans. It was a bad idea to generalize too quickly across species about that drug, and that should tell us something about generalizing across species about social and emotional development.
Do Animals Have Babysitters? An Important Aspect of Human Child Care
A recent book by the anthropologist Sarah Hrdy (“Mothers and Others: The Evolutionary Origins of Mutual Understanding”, Harvard University Press, 2009), describes some important differences between the great apes and human beings in hunter-gatherer groups. Apes and humans are noticeably different in their reproductive and infant-care behaviors, and Hrdy proposes that these differences are important for our understanding of human development. Among the great apes, females give birth only every 6 to 8 years. Hunter-gatherer women usually give birth every 3 or 4 years. Yet apes mature more quickly than humans, so the ape big brother or big sister is almost an adult by the time the next infant is born, while the human child is still very much in need of adult care when the next baby comes. The mother ape invests many years’ work in bringing one offspring near to maturity before taking on the next, but the human may have several children who simultaneously require a great deal of adult nurturance and supervision. Human children particularly need the kind of personal attention that fosters language development, or they will not grow up to be functioning members of their group.
How is this apparently paradoxical situation to be understood? Sarah Hrdy suggests that one very big difference between humans and great apes lies in the number of caregivers each infant has. Ape mothers do not like other apes to so much as touch their young infants. Although other apes play with and help the juvenile apes as they get older, the mother is pretty much on her own in early infant care. Not so with human beings, however. Human mothers allow and even encourage familiar adults to be in contact with their babies. Those adults can and do provide important aspects of care-- not just feeding and cleaning, but the social interactions, gestures, and sounds that contribute to development of communication and speech. In the evolutionary development of our species, Hrdy believes, there were advantages for babies who were good at engaging with adults and getting cared for. Skill at understanding what other people felt and intended would also be advantageous. Those babies would be more likely to survive, grow to maturity, and reproduce, passing on their genetic material and the behavior traits associated with it. Those useful traits would be more important for humans, who might depend on many adults for care, than for apes who initially were cared for by their mothers alone.
It’s interesting to speculate on whether attachment-- the strong preference of humans for staying near familiar people at times of threat-- would also have emerged from having a mother who would tolerate other caregivers for her baby. A toddler who was very engaging might be likely to approach and communicate with strangers, who might then take the baby away-- unless internal attachment processes made it less likely that the child would approach completely unfamiliar people. A baby who was jealously guarded by its mother, as occurs among the great apes, would not need attachment processes to keep it near the family; the mother would do this job. Although attachment is often thought of as the “invisible playpen” that would have kept our ancestors’ babies out of danger from fire and wild animals, we see another important dimension when we realize that the babies’ ability to get attention from adults might have put them in danger of kidnapping or death from enemy humans. If they could crawl or toddle, but did not have the emotional attachment that would warn them away from strangers, they might not live to grow up; when they became mobile, the emergence of attachment and stranger anxiety would keep them safer.
Although social interaction, communication, and forms of attachment occur in species other than our own, it’s not necessarily correct to assume that any of those behaviors is the same in every species. I recently received a journal reviewer’s comment that referred to attachment as “transspecific” (occurring across species). Although that is true, it’s less correct to assume that attachment is “panspecific” (occurring in all species in the same way). Some behaviors of human and animal babies seem so parallel that we tend to think of them as identical when they may not be so. But no human baby exists without adult caregivers, and few animal babies can. That means that in order to understand parallels between humans and animals, we may need to look at adult caregiving behavior as well as at the babies’ own actions. Humans use babysitters, animals don’t--- and many other differences may follow from those facts.
How is this apparently paradoxical situation to be understood? Sarah Hrdy suggests that one very big difference between humans and great apes lies in the number of caregivers each infant has. Ape mothers do not like other apes to so much as touch their young infants. Although other apes play with and help the juvenile apes as they get older, the mother is pretty much on her own in early infant care. Not so with human beings, however. Human mothers allow and even encourage familiar adults to be in contact with their babies. Those adults can and do provide important aspects of care-- not just feeding and cleaning, but the social interactions, gestures, and sounds that contribute to development of communication and speech. In the evolutionary development of our species, Hrdy believes, there were advantages for babies who were good at engaging with adults and getting cared for. Skill at understanding what other people felt and intended would also be advantageous. Those babies would be more likely to survive, grow to maturity, and reproduce, passing on their genetic material and the behavior traits associated with it. Those useful traits would be more important for humans, who might depend on many adults for care, than for apes who initially were cared for by their mothers alone.
It’s interesting to speculate on whether attachment-- the strong preference of humans for staying near familiar people at times of threat-- would also have emerged from having a mother who would tolerate other caregivers for her baby. A toddler who was very engaging might be likely to approach and communicate with strangers, who might then take the baby away-- unless internal attachment processes made it less likely that the child would approach completely unfamiliar people. A baby who was jealously guarded by its mother, as occurs among the great apes, would not need attachment processes to keep it near the family; the mother would do this job. Although attachment is often thought of as the “invisible playpen” that would have kept our ancestors’ babies out of danger from fire and wild animals, we see another important dimension when we realize that the babies’ ability to get attention from adults might have put them in danger of kidnapping or death from enemy humans. If they could crawl or toddle, but did not have the emotional attachment that would warn them away from strangers, they might not live to grow up; when they became mobile, the emergence of attachment and stranger anxiety would keep them safer.
Although social interaction, communication, and forms of attachment occur in species other than our own, it’s not necessarily correct to assume that any of those behaviors is the same in every species. I recently received a journal reviewer’s comment that referred to attachment as “transspecific” (occurring across species). Although that is true, it’s less correct to assume that attachment is “panspecific” (occurring in all species in the same way). Some behaviors of human and animal babies seem so parallel that we tend to think of them as identical when they may not be so. But no human baby exists without adult caregivers, and few animal babies can. That means that in order to understand parallels between humans and animals, we may need to look at adult caregiving behavior as well as at the babies’ own actions. Humans use babysitters, animals don’t--- and many other differences may follow from those facts.
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