So , we've evolved to be nice to kin, and this is influencer psychology in certain ways and the most obvious examples of this concern our relationships to our children because we are most related to our children and our children are most related to us. This is particularly the case for the psychology of birds and mammals including humans as opposed to fish and reptiles. Because birds and mammals invest in quality not quantity. We have relatively few offspring so, it's important that we take care of them and that they survive. One of the interesting evolutionary features of creatures like us is that there's a long period of dependence prior to sexual maturity. So this is in some way a biological adaptation, we have slowed down our course of growth. So, we spend this time learning and adapting to our environment before making it out in the world as sort of separate and distinct agents. As a psychologist, there are now two separate psychological stories we have to ask. The first is, what are the psychological mechanisms of childcare of how parents respond to children? The second is, what are the psychological mechanisms underlying how children respond to parents? We know a little bit about the psychology of how we respond to children. For instance, we are wired up to like children, we are wired up to respond to their distress calls which would be like crying in humans, we're wired up to find them cute. So, this picture if you Google images and type in cute baby this is one of the things that come up. There are certain features that are present in young mammals across not just humans but other mammals, a large protruding forehead, big eyes, upturned nose, chubby cheeks and we're wired up to find this cute. So, this evolved for dealing with children. What's interesting and an example of an evolutionary accident is that when we see the same features in adults, that influences our perception of them. So, some adults have baby faces and when we see a baby face, Leonardo DiCaprio is example of an adult with a baby face, relatively speaking. We tend to think of them more as naive, and helpless, and kind, and warm. Even though we can tell that they're not really younger and while we respond to somebody who has more of less of a baby's face more of a male testosterone face for men like Ben Affleck we don't think of them in the same way, we don't think of them as naive, helpless, kind, and warm. This is an example of the psychologies and the byproducts of this adaptations that direct us towards children. Then from the child side, children have evolve to develop attachment to adults, and so they will typically attached to whoever's closest, whoever takes care of them, and for a young baby will typically prefer the voice, and face, and smell of the mother and when the baby's able to explore to cuddle around, it will come back to the mother. You wonder why? What's the psychological mechanism underlying that. There's different theories. One theory is what's sometimes called a cupboard theory by BF Skinner. So, we looked at his theory of operand conditioning, before and from an operand conditioning standpoint a reinforcement and reward and punishment, the mother's rewarding, the mother gives milk for instance, and so that's why the baby comes back to the mother because of the rewards that the mother yields. A related theory but quite different, is developed by a psychologist Bowlby, and Bowlby unlike Skinner, points to innate tendency specifically evolved for attachment, and argues that there's two forces going on. One is a positive force. Babies are drawn to her mother for comfort and social interaction and physical warmth. This feeling of cuddling and a negative force a fear of strangers that drives babies away from individuals who aren't familiar who they aren't attached to. There's been some lovely experiments that presents some evidence for the innate Attachment Theory by Bowlby, some which are done with nonhuman primates. I'll end this part of the lecture by showing you a brief clip from a famous experiment designed to look at the nature of attachment. Let me show you a monkey raised on a nursing wire mother. Now, here are 106's two mothers. As you can see, it was ringed on a wire mother. Here's baby 106. He's going to the wire mother got the [inaudible]. Oh he's going back, he's back on the cloth mother and he'll stay on the cloth mother. Actually this baby spent some 17 hours a day on the cloth mother and less than one hour a day on the wire mother. We had predicted that the variable of contact comfort, would be a variable of measurable importance. But we were unprepared to find that it completely overwhelmed and overshadowed all other variables, including those of nursing. Frankly doctor, if it comes to a choice between wire and cloth, it's reasonable to expect that any child will go to the cloth, that's a matter of creature comfort like a baby with its blanket. But is this really love? Well, what do you mean by saying that a baby loves its mother? Certainly one thing we mean is that it gets a great feeling of security in the presence of the mother. Now, Mr. Collingwood wouldn't you say that if you frightened a baby, that it went running to its mother was comforted and then all the fear disappeared and was replaced by a complete sense of security that that baby loved its mother? Now, in this experiment, this is the apparatus we use. That looks diabolical. That's just the way the baby monkey feels about it. Lighting eyes, loud sound, moving mechanical parts, all of these things are designed to frighten a monkey. Now here we have a peaceful resting baby monkey. Let's find out what his reactions to his mother are when we frighten him. He's scared all right. Just like any child will do in a similar situation. He runs away. It's more than running away, he was writing to his mother to touch him to drive away his fear. Contact with the mother changes his entire personality. Look, now he's actually threatening the diabolical object. All right. This gives us part of the picture of this thing the infantal love.