Themes
Key
LitCharts assigns a color and icon to each theme in Survival of the Sickest, which you can use to track the themes throughout the work.
Evolution and Illness
Interspecies Connectivity and Adaptation
Environment, Ancestry, and Race
Genetic Expression, Acquired Traits, and Mutation
Interdisciplinary Science and Research
Summary
Analysis
Sharon Moalem tells the reader that this book is about miracle of life and the medical wonders, myths, and mysteries it contains. He shares one such mystery of his own: when Moalem was 15, his 71-year-old grandfather was diagnosed with Alzheimer’s disease. As a young man, it’s incredibly painful for Moalem to watch someone he loves suffer, and he wants answers as to why this is happening. Another aspect of his grandfather’s health further confuses Moalem: his grandfather has a lifelong love of donating blood, not only for the satisfaction of performing a good deed, but because he claims it alleviates his aches and pains. Puzzled by this and distraught over his grandfather’s ever-diminishing memory, Moalem believes it’s his responsibility to solve both mysteries.
Moalem opens with a personal anecdote that introduces disease as the primary concern of the book. His own feelings of pain, helplessness, confusion over his grandfather’s Alzheimer’s diagnosis show how devastating illness can be, especially when one doesn’t understand the root cause of the problem. Young Moalem’s decision to singlehandedly take on the challenge of solving his grandfather’s medical mystery implicitly encourages readers to take a similar hands-on, self-motivated approach. By emulating young Moalem’s attitude, people can learn more about the conditions that they and their loved ones face rather than defeatedly accepting ill health.
Themes
Moalem convinces his father to take him to a medical library, where he relentlessly searches for insight into his grandfather’s health. He knows that his grandfather is giving up iron when he donates blood, so he pores over books about this element and stumbles upon his answer: a disease called hemochromatosis. This hereditary condition causes excess iron to build up in the body to the point that it can damage major organs. Giving blood is the most effective way to reduce the body’s iron levels, so Moalem intuits that the reason his grandfather feels better when he donates blood is because it’s treating his undiagnosed hemochromatosis.
Again, Moalem’s self-driven pursuit for answers emphasizes the importance of scientific research (even into seemingly disparate topics) when trying to make sense of medical mysteries. The chance discovery that Moalem’s grandfather’s love of donating blood is actually rooted in a disease confirms this. Meanwhile, the fact that hemochromatosis is hereditary sets up another one of the book’s most important, though counterintuitive, ideas: that often, even diseases we view as undesirable and debilitating are able to survive in the gene pool.
Themes
Moalem has a feeling that his grandfather’s hemochromatosis and Alzheimer’s are somehow connected—after all, if hemochromatosis can damage major organs like the liver, why couldn’t it damage the brain? Unfortunately, no one takes 15-year-old Moalem seriously. But a few years later, Moalem chooses to major in biology in college, determined to continue pursuing the link between his grandfather’s two diseases. After graduating, he even delays going to medical school to pursue a PhD in neurogenetics. Two years later, his research uncovers the answer he’s been searching for: there is indeed a genetic association between hemochromatosis and Alzheimer’s. Though Moalem’s grandfather has already passed away at this point, Moalem feels hopeful that this discovery could help others.
Moalem’s intuition that hemochromatosis and Alzheimer’s must be related—and his years-long persistence in uncovering the link between the two—once again advocates for the importance of targeted and shrewd medical research into not only the root causes of diseases, but the connections among them. The fact that his hunch is ultimately proven right further emphasizes the importance of research for the betterment of humanity on a broad scale.
Themes
Moalem reveals that he, too, has hemochromatosis. When he gets diagnosed at 18, he wonders why so many people (30 percent of those with Western European ancestry) inherit the gene for this disorder. Why, he wonders, does evolution enable harmful traits like this to persist? This, Moalem says, is what Survival of the Sickest is about. Rather than just looking at symptoms and treatments, Moalem wants to uncover the evolutionary roots of diseases in the hopes that a deeper understanding will lead to helping people live longer and healthier lives—much like how Moalem himself has been able to manage his hemochromatosis.
The fact that both Moalem and his grandfather, along with 30 percent of people with Western European ancestry, have hemochromatosis is significant—there must be some underlying reason why a seemingly terrible disease has persisted in the gene pool over time. With this in mind, Moalem presents the thesis of the book: he aims to trace the evolutionary history of inherited diseases like hemochromatosis in order to better understand why they came about, why they were passed on, and how we can better treat them going forward.
Themes
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First, Moalem says, this book will examine hereditary disorders and why they persist in the gene pool. Second, it will delve into how our ancestors’ environments shaped our genes. Third, the book will show how the evolution of other organisms can give us insight into our own. Through this, Moalem hopes to impart a sense of reverence for the planet onto the reader, as well as to help them feel more in control of the future by giving them a more comprehensive understanding of the past. Before the reader continues on, Moalem encourages them to remember four things: that human life is interconnected with all other life, that the evolution of all organisms is interrelated, that genetic mutation isn’t inherently bad, and that one’s DNA isn’t set in stone.
Here, Moalem offers a brief outline of the book’s topics. In addition to showing how the diseases we inherit are rooted in our ancestry, Moalem will also show how humans (and our evolution) are connected to all of Earth’s other life-forms. As such, he hopes to inspire curiosity and wonder in the reader, as well as to provide a more nuanced understanding of evolution and disease. Moalem also aims to debunk common misconceptions—like that genetic mutation is always bad or that one’s genetic code is the be-all-end-all of one’s health—in order to better inform the reader and help them take control of their own lives.
Themes
