The Differential Adaptation Of A Species
One of the most widespread and misconceived ideas are: The human being is the best-adapted animal on Earth and Were at the top of the evolutionary pyramid. If we look at the definition of adaptation, well see that it consists of surviving and having offspring that survive. In short, adaptation means maintaining the existence of the species. In addition, we can deduce that all species that currently exist have also adapted. This is because you either exist or you dont exist.
Given this, many will allude to the great achievements of human beings or their high intellectual capacity in order to differentiate them from other living things. Just as the cat used its claws to survive, human beings used their intellect. Each species has different qualities that allow them to survive.
Its true that human beings have build complex societies in order to achieve this, whereas a bacterium simply does so with its resistance and high reproductive capacity. However, we can think of human beings as students who are struggling to pass a class, whereas bacteria are the students who study on the day of the test and pass. In the end, the result is the same for both.
Darwins Theory Of Natural Selection
Between December of 1831 and October of 1836, Charles Darwin took one of the most important geographic and intellectual journeys in recorded history. On this voyage he collected fossils and observed many forms of wildlife. Upon returning to England and examining his evidence, Darwin detected patterns in variations of animals seemingly related to environmental conditions. For example, he observed that the size and form of a species of birds beaks appeared related to the types of available foods . Eventually he published The Origin of Species , arguably the most influential book in the history of biological science.
Figure 2.1 Darwins finches
Darwin was familiar with the selective breeding practices of farmers designed to result in improved stocks. He reasoned that a similar selective process could occur as the result of natural causes . That is, if environmental factors resulted in some animals having an adaptive advantage relative to others, those animals would be more likely to survive long enough to reproduce. With respect to the birds, those possessing the type of beak best suited to eating the available food type would be able to consume more food and be more likely to survive. Similarly, if some animals possessed a characteristic resulting in their being more attractive to potential mates, they would be more likely to breed .
Figure 2.2 Sexual selection
A Adaptation And Adaptivity
That our evolutionary history influenced not only our bodies, but also our brains, and thus our minds, is not very controversial. But how exactly has evolution affected the way we are, mind-wise? How exactly can evolutionary theory elucidate the structure and function of the human mind?
It may seem that behavioral traits are like any other class of characters , so that they can be subject to natural selection in the same way as physiological traits. In that case, an evolutionary study of human behavior could then proceed by studying behavioral variants and see which of them are adaptive and which selectively neutral or detrimental. However, since natural selection is heritable variation in fitness, it can act only on entities that are transmitted between generations, and behavior as such is not directly transmitted between generations, but only via the genes that code for the proximal cognitive mechanisms that trigger it. Hence, o speak of natural selection as selecting for behaviors is a convenient shorthand, but it is misleading usage. Natural selection cannot select for behavior per se it can only select for mechanisms that produce behavior .
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Applications Of Evolutionary Psychology And Prospects For Further Debate
Finally, philosophers of science will doubtless continue to check thecredentials of evolutionary ideas imported into other areas ofphilosophy. Philosophers of biology in particular, still voicesuspicion if philosophers borrow their evolutionary ideas fromevolutionary psychology rather than evolutionary biology. PhilipKitcher voices this concern with regards to SharonStreets appeals to evolution. Kitcher worries thatStreet does not rely on what is known about humanevolution to provide an account of how her traitsof interest may have emerged. As noted above, Macherys nomological notion of human nature iscriticized on the grounds that he takes his idea of an evolved traitfrom evolutionary psychology as opposed to evolutionary biology.Barker also encourages philosophers, as well as socialscientists, to draw from the huge range of theoretical resourcesevolutionary biologists have to offer, rather than just from thoseprovided by evolutionary psychologists.
The Nature Of Selection Processes
Darwinism, or selectionism as the approach is more generally known, provides an account of the origins of complexity that does not entail principles that directly impose complexity . Instead, complexity is a possiblealthough not inevitableoutcome of the repeated action of lower-order processes. As a general approach, the potential range of selectionism extends far beyond evolutionary biology. Any limitations of selectionism arise primarily from pretheoretical commitmentsparticularly the sort of implicit rationalism that pervades many accounts of human behavior, as in much of linguistics and cognitive psychology . Selectionism has been productively instantiated in such diverse fields as the design of electronic circuits , economics , and cosmology .
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Explaining Aggression Through Evolutionour Ancestors Were Idiots
Charles DarwinThe Origin Of SpeciesTheory of EvolutionSTOP!Stop right there.”Ape-like ancestors”.NOT “apes”. Chimpanzees and gorillas and orangutans are apes. We’re not descended from them. But they are descended from the same “ape-like ancestors” as us, 6-16 million years ago.NOT “monkeys”. Monkeys have tails. Monkeys are a different group of animals. We’re not descended from monkeys. But our ape-like ancestors and monkeys are both descended from some earlier animals that lived 20 million years ago.It looks like this:Don’t let anyone tell you that we’re descended from apes. Apes might feel offended by that. But us and the apes share a common ancestor together, we’re known as the “hominids”Natural selectionsurvival traits Survival traits are anything that helps an animal survive and reproduce. This can be things like speed and strength, but it can also be cunning or stealth. Things that attract mates are survival traits. So are things that help reach food .Humans have many survival traits. Important ones are intelligence, team work and using tools. Aggression is an important survival trait, which is why the limbic system and hormones produce aggression. Too little aggression and you don’t get to eat or reproduce, too much and you get killed .Genetic mutation iDid someone say “mutants”?Evolutionary psychology9-minute video with a very simple explanation of Darwin’s discoveries and natural selection“Survival of the Fittest”Survival of the Fittest
What Do You Think
NATURAL SELECTION AND GENETIC DISEASES
If Darwin was right about natural selection, then why dowe have so many harmful genetic disorders? Consider,for example, cystic fibrosis, a hereditary disorder of Eu-ropean origin that clogs ones lungs with mucus andprevents digestion, typically causing death before age30. Another example is sickle-cell anemia, which causesearly deaths in many people of African descent. Can youreconcile the existence of such disorders with survivalof the fittest? Think about it, then see page 90.
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Evolutionary psychology uses evolutionary theory to explain similarities inpsychological characteristics. According to evolutionary psychologists, patterns ofbehavior have evolved through natural selection, in the same way that physicalcharacteristics have evolved. Because of natural selection, adaptivebehaviors, or behaviors that increase reproductive success, are kept andpassed on from one generation to the next.
Evaluating The Evolution Of Aggressionao3
CredibilityObjectionsDifferencesThe Exam Board expects you to compare the evolutionary explanation of aggression with the Freudian explanation of aggression. Freud’s ideas are explained on another page. For now, I’ll compare and contrast the biological explanation with the empiricist explanation that aggression is learned.Learning ApproachBehaviourists tabula rasaBiological determinists predispositions Applicationsparticularly
Man had emerged from the anthropoid background for one reason only: because he was a killer. Long ago, perhaps many millions of years ago, a line of killer apes branched off from the non-aggressive primate background. … We learned to stand erect in the first place as a necessity of the hunting life. … And lacking fighting teeth or claws, we took recourse by necessity to the weapon – Robert Ardrey
Scene from “2001: A Space Odyssey “, in which the first human tool is a weapon. When the killer ape throws the bone, a million years pass and it becomes a space ship orbiting Earth.Man the HuntedThe film “Ice Age” makes a very different point, that cooperation and self-sacrifice are the key to survival
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The Massive Modularity Hypothesis
Claims that the mind has a modular architecture, and even massivelymodular architecture, are widespread in cognitive science . The massive modularity thesis is firstand foremost a thesis about cognitive architecture. As defended byevolutionary psychologists, the thesis is also about the source of ourcognitive architecture: the massively modular architecture is theresult of natural selection acting to produce each of the many modules. Our cognitivearchitecture is composed of computational devices, that are innate andare adaptations . This massively modular architecture accountsfor all of our sophisticated behavior. Our successful navigation ofthe world results from the action of one or more of our manymodules.
There are many arguments for the massive modularity thesis. Some arebased upon considerations about how evolution must have acted someare based on considerations about the nature of computation and someare versions of the poverty of the stimulus argument first presentedby Chomsky in support of the existence of an innate universal grammar. Myriad versions of each of these argumentsappear in the literature and many arguments for massive modularity mixand match components of each of the main strands of argumentation.Here we review a version of each type of argument.
Response By Evolutionary Psychologists
Evolutionary psychologists have addressed many of their critics , Barkow , and Alcock ,). Among their rebuttals are that some criticisms are straw men, or are based on an incorrect nature versus nurture dichotomy or on misunderstandings of the discipline.Robert Kurzban suggested that “…critics of the field, when they err, are not slightly missing the mark. Their confusion is deep and profound. It’s not like they are marksmen who can’t quite hit the center of the target they’re holding the gun backwards.”
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Principles Of Evolutionary Psychology
Evolutionary psychology is a well-defined discipline of study and research, with fundamental foundations that have developed and continue to guide new studies. There are five basic principles of evolutionary psychology:
- Your brain is a physical system that instructs you to behave in a manner appropriate and adaptive to your environment.
- The neural circuitry of your brain helps you solve problems in an appropriate manner. The specific ways that the neural circuitry is constructed were directed by natural selection, over the course of generations.
- Most of your psychological behaviors are determined subconsciously by your neural circuitry, and you are largely unaware of these subconscious processes. You rely on conscious decision-making to guide you in your daily life, and you may be aware of the conclusions resulting from the complex neural circuitry while remaining unaware of the underlying process involved.
- Neural circuits in the brain are specialized to solve different adaptive problems. For example, the circuitry involved in vision is not the same as for vomiting.
- Your mind is based on adaptive changes that originated in the Pleistocene era.
Antisocial And Criminal Behavior
Evolutionary psychology has been applied to explain criminal or otherwise immoral behavior as being adaptive or related to adaptive behaviors. Males are generally more aggressive than females, who are more selective of their partners because of the far greater effort they have to contribute to pregnancy and child-rearing. Males being more aggressive is hypothesized to stem from the more intense reproductive competition faced by them. Males of low status may be especially vulnerable to being childless. It may have been evolutionary advantageous to engage in highly risky and violently aggressive behavior to increase their status and therefore reproductive success. This may explain why males are generally involved in more crimes, and why low status and being unmarried are associated with criminality. Furthermore, competition over females is argued to have been particularly intensive in late adolescence and young adulthood, which is theorized to explain why crime rates are particularly high during this period. Some sociologists have underlined differential exposure to androgens as the cause of these behaviors, notably Lee Ellis in his evolutionary neuroandrogenic theory.
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Natural Selection Of Species Is Misleading
The good of the species is a common misconception. It comes about because most of an animals life is devoted to reproduction, and most of the selfless acts an animal performs are for its offspring. Therefore, it seems like creatures act as they do in order to continue the species.
However, the point is that creatures ultimate goal cant be the survival of the species as a whole, or such selfish behaviors wouldnt exist in nature. The truth is that nature is fiercely competitive, with members of the same population having to fight each other for limited resourcesand, therefore, for survival. This is called natural selection: Organisms who are fit enough to survive and reproduce in their environments will be the ones to pass on their genes to the next generation.
What Is Darwins Theory Of Natural Selection Based On
The core of Darwin’s theory is natural selection, a process that occurs over successive generations and is defined as the differential reproduction of genotypes. Natural selection requires heritable variation in a given trait, and differential survival and reproduction associated with possession of that trait.
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A The Computational Model Of The Mind
Following the development of modern logic and the formalization of the notion of computation , early AI construed logical operations as mechanically executable information processing routines. Eventually, this led to the idea that mental processes and mental states may themselves also be analyzable in purely syntactic terms. The Computational Theory of Mind, developed by philosophers like Hilary Putnam and Jerry Fodor , for instance, conceives of mental states as relations between a thinker and symbolic representations of the content of the states, and of mental processes as formal operations on the syntactic features of those representations.
Evolutionary Psychology endorses the computational model of the mind as an information processing system or a formal symbol manipulator and thus treats the mind as a collection of computational machines or information-processing mechanisms that receive input from the environment and produce behavior or physiological changes as output. To this, it adds an evolutionary perspective: The evolutionary function of the human brain is to process information in ways that lead to adaptive behavior the mind is a description of the operation of a brain that maps informational input onto behavioral output . The brain is thus not just like a computer. It is a computerthat is, a physical system that was designed to process information .
Examples Of Empirical Research
Evolutionary Psychology has sparked an enormous amount of empirical research covering nearly any imaginable topic, including issues as diverse as language, morality, emotions, parental investment, homicide, social coercion, rape, psychopathologies, landscape preferences, spatial abilities, or pregnancy sickness .
David Buss has argued that there are major differences between males and females regarding mate choice and jealousy that are evolved responses to different selection pressures . For instance, he reasoned that because men need to guard against cuckoldry, while women need to guard against losing their mates economic resources, men should be concerned more by signs of sexual infidelity than about the loss of their partners emotional attachment, while women should be troubled more by cues that signal emotional infidelity than by signs of sexual infidelity. Buss et al. asked males and females from the USA, Europe and Asia whether they would be more distressed by sexual or emotional infidelity:
Please think of a serious committed romantic relationship that you have had in the past, that you currently have, or that you would like to have. Imagine that you discover that the person with whom youve been seriously involved became interested in someone else. What would distress or upset you more :
Imagining your partner forming a deep emotional attachment to that person.
Imagining your partner enjoying passionate sexual intercourse with that other person.
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Historic And Systematic Roots
Modern Evolutionary Psychology has its roots in the late 1980s and early 1990s, when psychologist Leda Cosmides and anthropologist John Tooby from Harvard joined the anthropologist Donald Symons at The University of California, Santa Barbara where they currently co-direct the Center for Evolutionary Psychology. It gained wide attention in 1992 with the publication of the landmark volume The Adapted Mind by Jerome Barkow, Leda Cosmides and John Tooby, and since then numerous textbooks and popular presentations have appeared. These days, Evolutionary Psychology is a powerful research program that has generated some interesting research, but it has also sparked a heated debate about its aspirations and limitations .
Evolutionary Psychology is effectively a theory about How the Mind Works . The human mind is not an all-purpose problem solver relying on a limited number of general principles that are universally applied to all problemsa view that dominated early artificial intelligence and behaviorism . Rather, the human mind is a collection of independent, task-specific cognitive mechanisms, a collection of instincts adapted for solving evolutionary significant problems. The human mind is sort of a Swiss Army knife . This conception of the mind is based on three important ideas adopted from other disciplines : the computational model of the mind, the assumption of modularity, and the thesis of adaptationism.
C Untestability And Story Telling
One of the key problems for Evolutionary Psychologists is to show that the adaptationist explanations they offer are indeed explanations properly so called and not mere just-so-stories that feature plausible scenarios without its being certain that they are historical fact. Stephen Jay Gould, for instance, who famously criticized evolutionary biology for its unreflected and widespread adaptationism that tends to ignore other plausible evolutionary explanations , has argued that the sole task of Evolutionary Psychology has become a speculative search for reasons why a behavior that harms us now must once have originated for adaptive purposes .
First, however, this holds only for research that conforms to Cosmides and Toobys theoretical model . It does not apply to research that does not generate a prediction based on a putative problem, but tries to infer the historical function of an organisms traits from its current structure. Profets work on pregnancy sickness would be a case in point: here, one already knows the trait and merely speculates about its historic function, in contrast to the other cases, where the existence of the trait is inferred from evolutionary considerations about the problems prevalent in the EEA.
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