Born Together—Reared Apart


Book Description

The Minnesota Study of Twins Reared Apart startled scientists by demonstrating that twins reared apart are as alike, across a number of personality traits and other measures, as those raised together, suggesting that genetic influence is pervasive. Segal offers an overview of the study’s scientific contributions and effect on public consciousness.




The Trouble with Twin Studies


Book Description

The Trouble with Twin Studies questions popular genetic explanations of human behavioral differences based upon the existing body of twin research. Psychologist Jay Joseph outlines the fallacies of twin studies in the context of the ongoing decades-long failure to discover genes for human behavioral differences, including IQ, personality, and the major psychiatric disorders. This volume critically examines twin research, with a special emphasis on reared-apart twin studies, and incorporates new and updated perspectives, analyses, arguments, and evidence.




Twin Research for Everyone


Book Description

Twin Research: Biology, Health, Epigenetics, and Psychology is a comprehensive, applied resource in twinning and twin studies that is grounded in the most impactful findings from twin research in recent years. While targeted to undergraduate and graduate students, this compendium will prove a valuable resource for scholars already familiar with twin studies, as well as those coming to the field for the first time. Here, more than forty experts across an array of disciplines examine twinning and twin research methodologies from the perspectives of biology, medicine, genetic and epigenetic influences, and neuroscience. Chapters provide clear instruction in both basic and advanced research methods, family and parenting aspects of twinning, twin studies as applied across various disease areas and medical specialties, genetic and epigenetic determinants of differentiation, and academic, neurological and cognitive development. The presentation of existing studies and methods instruction empowers students and researchers to apply twin-based research and advance new studies across a range of biomedical and behavioral fields, highlighting current research trends and future directions. Offers unique insights into twinning rates, mechanisms and factors surrounding twinship Provides clear instruction on both basic and advanced twin research methods and study design Features leading international experts in twin biology, genetics, health and psychology Examines findings from recent twin studies across a broad array of health and behavioral studies




Twin Study


Book Description

In the sense that all stories have been written before, a truly startling piece of fiction may be the greatest literary feat possible. Enter Stacey Richter, a virtuoso contender for that very prize, whose offbeat characters manage to toe the line between eccentricity and banal daily life. Each story is organized around a pair of characters, and these characters are permitted to reach their full bizarre potential against mundane backdrops. The result is fiction that drives toward a place of surreal revelation, in these sometimes disturbing, often funny, short pieces. In Twin Study, Richter beautifully captures — albeit through unlikely exemplars — the essential experience of humanity.




Methodology for Genetic Studies of Twins and Families


Book Description

Few would dispute the truth of the statement `People are Different', but there is much controversy over why. This book authoritatively explains the methods used to understand human variation, and extends them far beyond the primary `nature or nurture' question. After chapters on basic statistics, biometrical genetics, matrix algebra and path analysis, there is a state-of-the-art account of how to fit genetic models using the LISREL package. The authors explain not only the assumptions of the twin method, but how to test them. The elementary model is expanded to cover sex limitation, sibling interaction, multivariate and longitudinal data, observer ratings, and twin-family studies. Throughout, the methods are illustrated by applications to diverse areas such as obesity, major depression, alcohol comsumption, delinquency, allergies, and common fears.




Born Together—Reared Apart


Book Description

The identical “Jim twins” were raised in separate families and met for the first time at age thirty-nine, only to discover that they both suffered tension headaches, bit their fingernails, smoked Salems, enjoyed woodworking, and vacationed on the same Florida beach. This example of the potential power of genetics captured widespread media attention in 1979 and inspired the Minnesota Study of Twins Reared Apart. This landmark investigation into the nature-nurture debate shook the scientific community by demonstrating, across a number of traits, that twins reared separately are as alike as those raised together. As a postdoctoral fellow and then as assistant director of the Minnesota Study, Nancy L. Segal provides an eagerly anticipated overview of its scientific contributions and their effect on public consciousness. The study’s evidence of genetic influence on individual differences in traits such as personality (50%) and intelligence (70%) overturned conventional ideas about parenting and teaching. Treating children differently and nurturing their inherent talents suddenly seemed to be a fairer approach than treating them all the same. Findings of genetic influence on physiological characteristics such as cardiac and immunologic function have led to more targeted approaches to disease prevention and treatment. And indications of a stronger genetic influence on male than female homosexuality have furthered debate regarding sexual orientation.




Twin Studies:


Book Description

This volume is about an ongoing long-term research initiative led by researchers from the School of Dentistry at the University of Adelaide. The aim of this book is to provide an overview of the studies of the teeth and faces of Australian twins and their families that have extended over more than thirty years.




Heredity, Environment, and Personality


Book Description

This volume reports on a study of 850 pairs of twins who were tested to determine the influence of heredity and environment on individual differences in personality, ability, and interests. It presents the background, research design, and procedures of the study, a complete tabulation of the test results, and the authors’ extensive analysis of their findings. Based on one of the largest studies of twin behavior conducted in the twentieth century, the book challenges a number of traditional beliefs about genetic and environmental contributions to personality development. The subjects were chosen from participants in the National Merit Scholarship Qualifying Test of 1962 and were mailed a battery of personality and interest questionnaires. In addition, parents of the twins were sent questionnaires asking about the twins’ early experiences. A similar sample of nontwin students who had taken the merit exam provided a comparison group. The questions investigated included how twins are similar to or different from nontwins, how identical twins are similar to or different from fraternal twins, how the personalities and interests of twins reflect genetic factors, how the personalities and interests of twins reflect early environmental factors, and what implications these questions have for the general issue of how heredity and environment influence the development of psychological characteristics. In attempting to answer these questions, the authors shed light on the importance of both genes and environment and form the basis for different approaches in behavior genetic research.




Twin Research for Everyone


Book Description

Twin Research: Biology, Health, Epigenetics, and Psychology is a comprehensive, applied resource in twinning and twin studies that is grounded in the most impactful findings from twin research in recent years. While targeted to undergraduate and graduate students, this compendium will prove a valuable resource for scholars already familiar with twin studies, as well as those coming to the field for the first time. Here, more than forty experts across an array of disciplines examine twinning and twin research methodologies from the perspectives of biology, medicine, genetic and epigenetic influences, and neuroscience. Chapters provide clear instruction in both basic and advanced research methods, family and parenting aspects of twinning, twin studies as applied across various disease areas and medical specialties, genetic and epigenetic determinants of differentiation, and academic, neurological and cognitive development. The presentation of existing studies and methods instruction empowers students and researchers to apply twin-based research and advance new studies across a range of biomedical and behavioral fields, highlighting current research trends and future directions. Offers unique insights into twinning rates, mechanisms and factors surrounding twinship Provides clear instruction on both basic and advanced twin research methods and study design Features leading international experts in twin biology, genetics, health and psychology Examines findings from recent twin studies across a broad array of health and behavioral studies




Nature's Thumbprint


Book Description

Examining the interactive roles of nature and nurture in psychological and physical development, Neubauer and Neubauer show how each person is greater than the sum of his or her parts. They discuss how temperament, tastes and skills unfold throughout life and the need for this to remain unimpeded.