Entwined Lives: Twins and What They Tell Us about Human Behavior

This book provides an encyclopedic overview of research about twins. When I first opened the book, my initial reaction was "ouch", because of the densely packed font. The reason for the denseness is that Segal has so many topics to cover and so much information to share with us that the letters had to be squeezed to get it all into one volume. But not to fear - - there are pictures sprinkled throughout the text.Segal, a twin herself, has been researching twins for over 20 years, since her undergraduate studies. This book sums up much of that research in a format that is approachable by general audiences (and includes extensive endnotes to help interested readers find the studies that are cited). The many topics in her book include: identical twins, fraternal twins, twins reared apart, children adopted together, conjoined twins, non-human twins, friendship between twins, loss of a twin, famous twins, mental skills, athletic skills, and behavioral traits. One of the most interesting results of Segal's and others' twin research is the strong influence that genes have on intelligence, behavioral traits, and athletic ability. Segal reports that identical twins, reared together or apart, are remarkably similar in these areas, and become more so as they get older. The similarity is weaker with fraternal twins, siblings, and cousins, and hardly found at all between unrelated same-aged children raised together. Certain health factors on the other hand, seem to be more dependent on environmental factors and life choices than on genetics, such as aging of the skin and heart disease. Many of Segal's results come from research on identical twins reared apart, in whom strong similarities point to genetic programming since the environments in which they were raised were different. The logical opposite of identical twins reared apart is unrelated same-aged children reared together, in whom any similarities would suggest environmental influences. Segal has a short chapter on such siblings, but this area could really use more research to complement what has been done with twins reared apart.This book is absolutely fascinating for what it says, not only about twins and other multiples, about the siblings and parents of twins, about adopted children, but also about humans in general.

I am very impressed with this book. It discusses several topics on twins that so many other books on this subject seem to miss. It also goes into great detail about often overlooked discussions on twins. It includes statistics, interviews, and a variety of research on twin studies. This book is not easy reading, though. It is written, I believe, for fellow professionals and twin researchers. It's not a "cozy, get through quick" book written for the average mom-of-twins like those that line the shelves of so many local bookstores. However, the extra time I took to read (and sometime re-read the statistics)the book was well worth it as this piece of literature left me with more information than I have received from dozens of other books on twins.

I love this book! It is a gold mine of information, of anecdotes, of insightful observations. Twin research to Segal is "bliss." She reveals this in the very personal "Afterword: Part of Me". Her enthusiasm is infectious. Her bliss in contagious. Entwined Lives is a monument to twinship. Segal's book comes with glowing tributes on the back from Professor David Lykken and Professor Irving Gottesman. Their enthusiasm for the book is surpassed by the enthusiasm of the author for her subject and all the twins she has met. The book is described with exclamation by Thomas J. Bouchard, Ph.D. in his Foreword as a "book extraordinaire!". It certainly is. Nancy Segal writes about twins with verve and enjoyment in a style which will appeal to the general reader. All readers, including academics, will learn. There are extensive notes and references for each chapter and a Glossary to explain more technical terms, although these are avoided where possible. The personal style of the book intentionally and very successfully allows easy translation of the technical into the generally comprehensible.

I bought this book because I am an identical twin and I was curious about recent research on twins. Segal is certainly the expert here. However she goes beyond just the facts of the studies and ties in lots of interesting information and theories about how genetics influences our behavior and our attachments to the people in our family. Her theories on the reasons for the closeness of a mother to her children were very interesting to me.This book has much to offer to different people - it discusses general interest topics like why we behave the way we do and end up a certain way. It should also be a "must read" for any identical twin or parent of a twin. Segal does an extraordinary job of describing the special relationship that exists between identical twins.

Dr. Nancy Segal has further drawn back the curtain shrouding the mysteries of human behavior with this enduring observation. I found the book reveals an enormous amount about ourselves through the study of twins. Dr. Segal is a gifted researcher with an exquisite writing style. She takes elaborate research topics and explains them in ways that we all can understand. Page after page, the book reveals new information about how we humans develop through nature and nurture, the end result being that our genetic design has more to do with who we are than we every imagined. The book gives us significant insight far beyond the surface interest most have in twins. I found the book also very entertaining with its numerous ancedotes and real-life stories about twins. Being a twin myself, the book helped me gain new perspective about my twinship and eliminate many eroneous perceptions/myths about twins.