By CASSANDRA GEISEN
—Interest in human genealogy can be traced to Biblical times with the mention in the Old Testament of Abraham’s siring Isaac, who fathered Jacob, who then begat Judas. Many of the ancient cultures, including those within Africa and China, have always placed great importance on ancestry and the need to know who we are and where we came from. Christine Kenneally’s beautifully rendered, exhaustively researched book, The Invisible History of the Human Race, begins with the premise that human beings today occupy an auspicious moment in history for discovering and better understanding their genetic and genealogical history. Because of enormous advances in DNA testing within the past 10 years alone, together with a wealth of knowledge and historical information now available through genealogical websites, we now have a far greater understanding of how our DNA has shaped our individual histories and continues to affect our daily lives.
The Invisible History of the Human Race:
How DNA and History Shape Our Identities and Our Futures
By Christine Kenneally
Published by the Penguin Group, 2014
“Within each of our cells,” Kenneally states, “is a library of DNA that has been passed down to us.” Genomes, the set of genes within us, are, according to Kenneally, the “human barcodes” that give us our identity, inherited from all of our family members who came before us. Many Americans, however, can barely identify three generations of previous ancestors. In contrast, the Chinese, who are noted for their detailed family record books called jai pu, can trace their genealogies back 2,500 years. The New Zealand Maori have also kept family history records for centuries and can trace their ancestral beginnings back more than 1,000 years. Western interest in genealogy only came about, according to Kenneally, with the rise and power of an aristocratic class in Europe. After European immigrants settled into the new colonies that would eventually become America, interest in genealogy continued to remain high as it established family pedigrees.
Yet, around the time of the Revolutionary War in the late 1700s, a backlash developed against genealogy because of the new ideals that emphasized equality among men. Still, property owners, in particular, continued to create legal records for themselves but women, slaves, and Native Americans were often omitted from official records. Gradually, it was regarded as distasteful to be curious about one’s ancestors. The pendulum swung in several directions, however, and eventually interest in one’s family tree became popular again in the US. Genealogists grew in number and started to exert their influence. As the field of genealogy grew, however, charlatans entered the profession and counterfeit lineages rose. Eventually, genealogy was barred from university studies in the US and the field was widely discredited. To this day, some still view the study of genealogy in the US States with skepticism. As scientific knowledge of genetics has grown exponentially, however, a desire to understand and embrace one’s unique genetic and genealogical footprint has soared. Advances in scientific research and tools have finally provided the field of genealogy and genetics the gravitas it deserves.
The Invisible History of the Human Race explains how genetic analysis can help us understand the missing links of our ancestry and the historical and cultural patterns that have influenced and even shaped our sense of taste and food choices. The gene for amalyses, as an example, helps humans process starch. There are genes that also assist humans in processing cow milk and wheat that were necessary for adapting to changing agricultural environments hundreds of years ago. Genetic analysis of our genes also explains the existence of “working genes,” used to identify bitterness, which once aided humans in avoiding poisonous foods. Humans possess other working genes, some of which are gradually disappearing as we distance ourselves further from the natural world. These working genes include a heightened ability to see, smell, and accurately identify pheromones.
Christine Kenneally shares a wealth of fascinating and uncommon data, gleaned from genetic, historical, and cultural research. We know, for example, that “the human tree originated in Africa hundreds of thousands of years ago and that genomes, or the genetic markers of everyone in the world outside of Africa, is a subset of the genomic variation still found in Africa.” We also know that a significant amount of Genghis Khan’s DNA remains in Asia today. This infamous, feared Mongol warlord and his empire were responsible for the slaughter of nearly 40 million human beings in the 12th and 13th centuries. Genghis Khan’s Y chromosome was passed down to many, many sons he fathered while eliminating the Y-chromosomes of millions of other males in the region. Khan’s sons continued to rule large swaths of Asia after his death, further spreading his gene pool long after he was gone.
Knowledge of our Neanderthal ancestors is another recent genetic discovery. “In just the last few years we have learned that 85 percent of all people carry DNA from Neanderthals, an entirely different species that lived until 27,000 years ago.” This interbreeding occurred,” according to Kennealy, “despite the fact that Homo sapiens and Neanderthals were distinct species.” Scientific research has also demonstrated that the Neanderthal genome helped make the first Eurasians lighter-skinned than their African ancestors and allowed them to adapt to a much colder climate. Humans’ skin color also grew lighter because of their need to generate more vitamin D in darker climates.
What makes our inherited DNA so fascinating to study is the manner in which our environment, our experiences, and our genetic history shape our individual lives, our opportunities, and our futures. Recent DNA discoveries and advances also are teaching us how DNA contributes to both common and hereditary diseases.
Christine Kenneally not only shares a wealth of fascinating data about recent genetic breakthroughs, but her book serves as a trove of information that can be integrated into ESL lesson plans on subjects such as geography, history, science, and culture. Kenneally, for example, traces geographic patterns of human migration that originated in Africa more than 250,000 years ago, eventually resulting in the settlement through the centuries of the other six continents. She highlights the similarity of ancestral worship practices in cultures within Africa, Australia, and Asia and discusses the science of genomes, how each human cell is a “massive library of DNA, three billion base pairs that have been passed down to us.”
Genomes have not only taught us about early human migration patterns but also about the influence of genes on human traits and diseases. We now know how many genes influence height (40) and how genes exert their influence by both chemical changes within our cells in addition to changes in the environment. Perhaps most significantly, Christine Kenneally’s book reveals the fact that “biological race” is an artificially created construct. Based upon genetic research we now understand that “there are more differences within populations—or what we think of as racial groups—than between them.” As such, human races and populations, despite differences such as physical characteristics, have far more in common and are more similar to each other than was previously known. This is a compelling fact that should be shared and emphasized with our ESL students.
Christine Kenneally’s The Invisible History of the Human Race is one of those rare literary gems that combine the very best of storytelling with the latest scientific discoveries. Kenneally, a linguist and a journalist, weaves a fascinating, true tale of the role that history and culture have played in shaping the human genome. The many unpredictable, nonreplicable experiences in our lives will continue to influence our genes, rendering human beings unique and truly one-of-a-kind.
Cassandra Giesen has taught high school Spanish, English, and ESL. She has a MA in Education with emphasis in TESOL from California State University, San Bernardino and regularly writes about education, culture, politics, and international relations. She lives in Marin County, California, with her husband and family.