LECTURE 13 EVOLUTIONARY PSYCHOLOGY 演化心理学
LECTURE 13 EVOLUTIONARY PSYCHOLOGY 演化心理学
NTRODUCTION Evolutionary psychology is one of many biologically informed approaches to the study of human behavior. Along with cognitive psychologists, evolutionary psychologists propose that much, if not all, of our behavior can be explained by appeal to internal psychological mechanisms What distinguishes evolutionary psychologists from many cognitive psychologists is the proposal that the relevant internal mechanisms are adaptations(适应器)- products of natural selection--that helped our ancestors get around the world, survive and reproduce. to understand the central claims of evolutionary psychology we require an understanding of some key concepts in evolutionary biology, cognitive psychology, philosophy of science and philosophy of mind
INTRODUCTION • Evolutionary psychology is one of many biologically informed approaches to the study of human behavior. Along with cognitive psychologists, evolutionary psychologists propose that much, if not all, of our behavior can be explained by appeal to internal psychological mechanisms. What distinguishes evolutionary psychologists from many cognitive psychologists is the proposal that the relevant internal mechanisms are adaptations(适应器）—products of natural selection—that helped our ancestors get around the world, survive and reproduce. To understand the central claims of evolutionary psychology we require an understanding of some key concepts in evolutionary biology, cognitive psychology, philosophy of science and philosophy of mind
NTRODUCTION Philosophers are interested in evolutionary psychology for a number of reasons For philosophers of science -mostly philosophers of biology--evolutionary psychology provides a critical target. There is a broad consensus among philosophers of science that evolutionary psychology is a deeply flawed enterprise. For philosophers of mind and cognitive science evolutionary psychology has been a source of empirical hypotheses about cognitive architecture and specific components of that architecture philosophers of mind are also critical of evolutionary psychology but their criticisms are not as all-encompassing as those presented by philosophers of biology. Evolutionary psychology is also invoked by philosophers interested in moral psycholog both as a source of empirical hypotheses and as a critical target
INTRODUCTION • Philosophers are interested in evolutionary psychology for a number of reasons. For philosophers of science —mostly philosophers of biology—evolutionary psychology provides a critical target. There is a broad consensus among philosophers of science that evolutionary psychology is a deeply flawed enterprise. For philosophers of mind and cognitive science evolutionary psychology has been a source of empirical hypotheses about cognitive architecture and specific components of that architecture. Philosophers of mind are also critical of evolutionary psychology but their criticisms are not as all-encompassing as those presented by philosophers of biology. Evolutionary psychology is also invoked by philosophers interested in moral psychology both as a source of empirical hypotheses and as a critical target
THE RESEARCH TRADITION OF EP Evolutionary psychology rests upon specific theoretical principles not all of which are shared by others working in the biology of human behavior. For example 1 human behavioral ecologists(人类行为学家) present and defend explanatory hypotheses about human behavior that do not appeal to psychological mechanisms. Behavioral ecologists also believe that much of human behavior can be explained by appealing to evolution while rejecting the idea held by evolutionary psychologists that one period of our evolutionary history in the source of all our important psychological adaptations(Irons 1998) 2. Developmental psychobiologists(发肓心理一生物学家) take yet another approach: they are anti-adaptationist. These theorists believe that much of our behavior can be explained without appealing to a suite of specific psychological adaptations for that behavior. Instead they emphasize the role of development in the production of various human behavioral traits From here on, "evolutionary psychology refers to a specific research tradition among the many biological approaches to the study of human behavior
THE RESEARCH TRADITION OF EP • Evolutionary psychology rests upon specific theoretical principles not all of which are shared by others working in the biology of human behavior. For example, • 1.human behavioral ecologists(人类行为学家) present and defend explanatory hypotheses about human behavior that do not appeal to psychological mechanisms. Behavioral ecologists also believe that much of human behavior can be explained by appealing to evolution while rejecting the idea held by evolutionary psychologists that one period of our evolutionary history in the source of all our important psychological adaptations (Irons 1998). • 2. Developmental psychobiologists （发育心理—生物学家）take yet another approach: they are anti-adaptationist. These theorists believe that much of our behavior can be explained without appealing to a suite of specific psychological adaptations for that behavior. Instead they emphasize the role of development in the production of various human behavioral traits. • From here on, “evolutionary psychology” refers to a specific research tradition among the many biological approaches to the study of human behavior
THEORY OF EP 1. The brain is a computer designed by natural selection to extract information from the environment 2. Individual human behavior is generated by this evolved computer in response to information it extracts from the environment Understanding behavior requires articulating the cognitive programs that generate the behavior 3. The cognitive programs of the human brain are adaptations. They exist because they produced behavior in our ancestors that enabled them to survive and reproduce 4. The cognitive programs of the human brain may not be adaptive now; they were adaptive in ancestral environments 5. Natural selection ensures that the brain is composed of many different special purpose programs and not a domain general architecture 6. Describing the evolved computational architecture of our brains allows a systematic understanding of cultural and social phenomena
THEORY OF EP • 1.The brain is a computer designed by natural selection to extract information from the environment. • 2.Individual human behavior is generated by this evolved computer in response to information it extracts from the environment. Understanding behavior requires articulating the cognitive programs that generate the behavior. • 3.The cognitive programs of the human brain are adaptations. They exist because they produced behavior in our ancestors that enabled them to survive and reproduce. • 4.The cognitive programs of the human brain may not be adaptive now; they were adaptive in ancestral environments. • 5.Natural selection ensures that the brain is composed of many different special purpose programs and not a domain general architecture. • 6. Describing the evolved computational architecture of our brains “allows a systematic understanding of cultural and social phenomena
METHODS OF EP The methods for testing hypotheses in evolutionary psychology come mostly from psychology For example, in Singh's work, male subjects are presented with drawings of women with varying waist hip ratios(腰臀比) and ask to give their preference rankings.n Buss's work supporting several hypothesized mate selection mechanisms, he performed similar experiments on subjects asking for their responses to various questions about features of desired mates(Buss 1990). Buss, Singh and other evolutionary psychologists emphasize the cross cultural validity of their results claiming consistency in responses across a wide variety of human For the most part standard psychological experimental methods are used to test hypotheses in evolutionary psychology. This has raised questions about the extent to which the evolutionary component of evolutionary psychologists hypotheses is being tested. A response profile may be prevalent in a wide variety of subject populations but this says nothing about whether or not the response profile is a psychological mechanism that arose from a particular selective regimen
METHODS OF EP • The methods for testing hypotheses in evolutionary psychology come mostly from psychology. For example, in Singh‘s work, male subjects are presented with drawings of women with varying waist hip ratios (腰臀比) and ask to give their preference rankings. In Buss's work supporting several hypothesized mate selection mechanisms, he performed similar experiments on subjects, asking for their responses to various questions about features of desired mates (Buss 1990). Buss, Singh and other evolutionary psychologists emphasize the cross cultural validity of their results, claiming consistency in responses across a wide variety of human. For the most part standard psychological experimental methods are used to test hypotheses in evolutionary psychology. This has raised questions about the extent to which the evolutionary component of evolutionary psychologists' hypotheses is being tested. A response profile may be prevalent in a wide variety of subject populations but this says nothing about whether or not the response profile is a psychological mechanism that arose from a particular selective regimen
The Massive Modularity Hypothesis We've talked about this in the last lecture
The Massive Modularity Hypothesis • We’ve talked about this in the last lecture
Philosophy of biology VS Evolutionary Psychology Many philosophers have criticized evolutionary psychology. Most of these critics are philosophers of biology For evolutionary psychologists, the most interesting contribution that evolutionary theory makes is the explanation of apparent design in nature or the explanation of the production of complex organs by appeal to natural selection. Evolutionary psychologists generate evolutionary hypotheses by 1. first finding apparent design in the world, say in our psychological make up, and then presenting a selective scenario that would have led to the production of the trait that exhibits apparent design 2. The hypotheses evolutionary psychologists generate, given that they are usually hypotheses about our psychological capacities, are tested by standard psychological methods Philosophers of biology challenge evolutionary psychologists on both of these points
Philosophy of biology vs. Evolutionary Psychology • Many philosophers have criticized evolutionary psychology. Most of these critics are philosophers of biology. • For evolutionary psychologists, the most interesting contribution that evolutionary theory makes is the explanation of apparent design in nature or the explanation of the production of complex organs by appeal to natural selection. Evolutionary psychologists generate evolutionary hypotheses by • 1. first finding apparent design in the world, say in our psychological make up, and then presenting a selective scenario that would have led to the production of the trait that exhibits apparent design. • 2.The hypotheses evolutionary psychologists generate, given that they are usually hypotheses about our psychological capacities, are tested by standard psychological methods. • Philosophers of biology challenge evolutionary psychologists on both of these points
What is an adaption? Sober makes a few further clarifications of the notion of adaptation that are helpful. 1. First, we should distinguish between a trait that is adaptive and a trait that is an adaptation. any number of traits can be adaptive without those traits being adaptations. A sea turtles forelegs are useful for digging in the sand to bury eggs but they are not adaptations for nest building(Sober 2000, 85) Also, traits can be adaptations without being currently adaptive for a given organism. Vestigial organs(退化器官) such as our appendix or vestigial eyes in cave dwelling organisms are examples of such traits (Sterelny and Griffiths 1999) 2. Second, we should distinguish between ontogenic(个体发育的) and phylogenetic(种系发肓的) adaptations( Sober200086).The adaptations of interest to evolutionary biologists are phylogenetic adaptations, which arise over evolutionary time and impact the fitness of the organism. ontogenetic adaptations including any behavior we earn in our lifetimes, can be adaptive to the extent that an organism benefits from them but they are not adaptations in the relevant sense
What is an adaption? • Sober makes a few further clarifications of the notion of adaptation that are helpful. 1.First, we should distinguish between a trait that is adaptive and a trait that is an adaptation. Any number of traits can be adaptive without those traits being adaptations. A sea turtles forelegs are useful for digging in the sand to bury eggs but they are not adaptations for nest building (Sober 2000, 85). • Also, traits can be adaptations without being currently adaptive for a given organism. Vestigial organs (退化器官) such as our appendix or vestigial eyes in cave dwelling organisms are examples of such traits (Sterelny and Griffiths 1999). • 2. Second, we should distinguish between ontogenic（个体发育的） and phylogenetic （种系发育的）adaptations (Sober 2000, 86). The adaptations of interest to evolutionary biologists are phylogenetic adaptations, which arise over evolutionary time and impact the fitness of the organism. Ontogenetic adaptations, including any behavior we learn in our lifetimes, can be adaptive to the extent that an organism benefits from them but they are not adaptations in the relevant sense
EP UNDERSTANDING OF ADAPTION adaptations, the functional components of organisms, are identified[.] by[.. evidence of their design: the exquisite match between organism structure and environment(Hagen 2005, 148) Reverse engineering is a process of figuring out the design of a mechanism on the basis of an analysis of the tasks it performs Evolutionary functional analysis is a form of reverse engineering in that it attempts to reconstruct the mind's design from an analysis of the problems the mind must have evolved to solve(Buller 2005,92)
EP’ UNDERSTANDING OF ADAPTION • “adaptations, the functional components of organisms, are identified […] by […] evidence of their design: the exquisite match between organism structure and environment” (Hagen 2005, 148). • “Reverse engineering is a process of figuring out the design of a mechanism on the basis of an analysis of the tasks it performs. Evolutionary functional analysis is a form of reverse engineering in that it attempts to reconstruct the mind's design from an analysis of the problems the mind must have evolved to solve” (Buller 2005, 92)