Module1.1 (3).pptx

Unit 1 – Biological Basis of Behavior 1.1 Heredity & Environment Veranda Colbert 2024-2025 AP Psychology Module 1.1 Interaction of Heredity and Environment 1.1-1 Describe evolutionary psychologists’ use of natural selection to explain behavior tendencies. 1.1-2 Describe how behavior ge...

Unit 1 – Biological Basis of Behavior 1.1 Heredity & Environment Veranda Colbert 2024-2025 AP Psychology Module 1.1 Interaction of Heredity and Environment 1.1-1 Describe evolutionary psychologists’ use of natural selection to explain behavior tendencies. 1.1-2 Describe how behavior geneticists explain our individual differences. 1.1-3 Explain how twin and adoption studies help us understand the effects and interactions of nature and nurture. 1.1-4 Explain how heredity and environment work together.  Nature vs. Nurture Debate The nature vs. nurture debate questions whether our traits are inherited, or shaped by our experiences Plato believed in the inheritance of character and intelligence, while Aristotle emphasized experience through the senses Today’s science views traits as arising from the interaction of both nature and nurture, a concept central to modern psychology. This debate, known as the nature-nurture issue, remains a foundational topic in psychology. Natural Selection and Psychology Charles Darwin’s theory of natural selection proposes that traits enhancing survival and reproduction are likely to be passed down. This principle is foundational in evolutionary psychology, explaining both physical traits and behaviors. Darwin's theory continues to influence psychology today, providing a framework for understanding behavior through an evolutionary lens. The idea is that adaptation helps organisms thrive in their environments. Evolutionary psychology: the study of the evolution of behavior and the mind, using principles of natural selection. Evolutionary Psychology Evolutionary psychology focuses on understanding human behavior by considering the evolutionary processes that shaped it. It looks at how shared biology and evolutionary history influence human similarities, such as common fears and social behaviors. This field examines how certain behaviors have been advantageous for survival across generations. Evolutionary psychologists often use the principle of natural selection to explain behavior and mental processes. Behavior Genetics How do we individually differ because of our differing genes and environments? – Behavior Genetics Behavior genetics explores how our genetic makeup and environment influence our behavior. It studies the relative power and limits of these influences, often using twin and adoption studies. This field highlights the complex interaction between heredity and experience, with an emphasis on polygenetic traits. Understanding this interaction helps explain individual differences in behavior and personality. Nurture works on what nature provides Gene-Environment Interaction Gene-environment interaction refers to the way our genes and experiences work together to shape who we are. Some traits, like intelligence or temperament, are expressed only in specific environments influenced by genetic predispositions. This interaction is central to understanding individual differences in behavior and is closely related to the concept of epigenetics. Epigenetics studies how environmental factors can turn genes on or off, affecting their expression.  The Nature of Epigenetics Epigenetics explores how environmental factors can affect gene expression without changing the DNA sequence. These changes can influence both physical and behavioral traits, sometimes across generations, and are often influenced by methylation. Epigenetics helps explain why identical twins may develop different traits, even when raised in similar environments. This field is advancing our understanding of the complex interaction between heredity and environment. Identical vs. Fraternal Twins Identical twins develop from a single fertilized egg and share the same genetic makeup, while fraternal twins develop from two separate eggs. Identical twins are often more similar in personality and behavior than fraternal twins, highlighting the role of genetics. Twin studies help researchers understand the influence of genetics versus environment, focusing on both monozygotic and dizygotic twins. Identical twins provide valuable insights into the nature-nurture issue. Twin and Adoption Studies Twin and adoption studies are essential for understanding the effects of heredity and environment on behavior. These studies compare identical and fraternal twins, as well as adopted children with their biological and adoptive families. The findings show that shared family environments have less impact on personality than genetics, revealing the influence of shared and nonshared environments. These studies shed light on the complex interaction of nature and nurture. Evolutionary Success and Human Similarities Human beings share deep genetic similarities due to evolutionary success. Despite cultural differences, people around the world share common behaviors and emotions, such as fear and social bonding. Evolutionary psychology explains these similarities by tracing them back to survival and reproductive advantages, which are part of our genetic legacy. Understanding these commonalities helps us appreciate the shared aspects of human nature. Our Genetic Legacy Our genetic legacy is a result of the evolutionary processes that have shaped our species. While humans share a common set of genes, individual differences arise from slight genetic variations, known as mutations. These variations contribute to the diversity we see in personality, intelligence, and other traits. Behavior genetics seeks to understand how these differences are shaped by both genes and the environment, often through studies of gene- environment interaction. Evolutionary Psychology and Modern Life Evolutionary psychology provides insights into how ancient survival mechanisms influence modern behavior. Many psychological traits that were advantageous in the past may be less adaptive in today's world, such as the stress response to threats. For example, our preference for high- calorie foods once helped us survive, but now contributes to health issues like obesity. This field helps explain the mismatch between our evolved tendencies and contemporary living. The Impact of Culture on Evolution Culture plays a significant role in shaping how evolutionary principles manifest in behavior. Cultural evolution occurs when human practices and beliefs change over time, influencing which behaviors are adaptive. Social norms around cooperation and competition can affect evolutionary success, highlighting the role of cultural transmission. Understanding the interaction between culture and evolution is key to grasping human development. Understanding Genetic Predispositions Genetic predispositions are tendencies encoded in our DNA that can influence behavior and health. However, these predispositions do not determine outcomes on their own, as environmental factors play a critical role. Epigenetic changes, such as those influenced by diet or stress, can modify how these predispositions manifest. This understanding is central to the study of health psychology and behavior genetics. Epigenetics and Long-Term Effects Epigenetic changes can have long-term effects on an individual's health and behavior. Factors like stress, diet, and exposure to toxins can alter gene expression and potentially be passed on to future generations. This challenges the traditional view that only DNA mutations can be inherited and emphasizes the role of epigenetic marks. Epigenetics could revolutionize our understanding of heredity and health. Natural Selection in Modern Contexts Natural selection continues to shape human behavior, even in modern contexts. Traits that once provided a survival advantage may still influence behaviors, such as fear responses or social bonding, seen in the fight or flight response. However, in today’s world, some of these traits may no longer be as beneficial, leading to issues like anxiety in response to modern stressors. Evolutionary psychology explores these nuances to better understand current human behavior. The Role of Mutations in Evolution Mutations are random changes in DNA that can lead to new traits or variations in existing ones. While many mutations are neutral or harmful, some provide advantages that can be selected for in a population, contributing to evolutionary change. These advantageous mutations contribute to the diversity within a species and are a key factor in natural selection. Understanding mutations is key to grasping how diversity arises within a species. Behavioral Tendencies and Survival Behavioral tendencies, such as aggression or cooperation, can be traced back to their survival value in ancestral environments. Evolutionary psychology suggests that these behaviors were selected because they enhanced survival and reproduction. Today, these tendencies are still present, although their expression may vary depending on the environment, influenced by gene-environment interaction. This perspective helps explain why certain behaviors are deeply ingrained in human nature. Contemporary Issues in Nature vs. Nurture The nature vs. nurture debate has evolved with advancements in genetics and psychology. Researchers now focus on how genes and the environment interact to shape behavior, often looking at polygenetic traits. Modern studies show that most traits are influenced by a complex interplay of multiple genes and environmental factors, highlighting the role of gene- environment interaction. This ongoing research continues to refine our understanding of human development. The Influence of Shared and Nonshared Environments Shared environments are the environmental factors shared by siblings raised in the same family, such as socioeconomic status or parental style. Nonshared environments are those unique to the individual, such as different peer groups or personal experiences. Research shows that nonshared environments often play a larger role in shaping individual differences in personality than shared environments. This distinction helps explain why siblings can be so different from one another. Nature-Nurture in Psychological Disorders The development of psychological disorders often involves an interaction between genetic predispositions and environmental triggers. Disorders like depression or schizophrenia are more likely to develop when individuals with a genetic susceptibility encounter stressful or adverse environments. Gene-environment interaction is crucial in understanding how certain individuals are more vulnerable to mental health issues than others. This insight is essential for developing effective prevention and treatment strategies.