Daniel E. Lieberman Quotes
“Our body’s evolutionary journey is also far from over. Natural selection didn’t stop when farming started but instead has continued and continues to adapt populations to changing diets, germs, and environments. Yet the rate and power of cultural evolution has vastly outpaced the rate and power of natural selection, and the bodies we inherited are still adapted to a significant extent to the various and diverse environmental conditions in which we evolved over millions of years. The end product of all that evolution is that we are big-brained, moderately fat bipeds who reproduce relatively rapidly but take a long time to mature.”
“The fundamental answer to why so many humans are now getting sick from previously rare illnesses is that many of the body's features were adapted in environments from which we evolved, but have become maladapted in the modern environments we have now created. This idea, known as the mismatch hypothesis, is the core of the new emerging field of evolutionary medicine, which applies evolutionary biology to health and disease.”
“When Franklin D. Roosevelt signed the Social Security Act in 1935, old age was defined as sixty-five years, yet estimated life expectancy in the United States at the time was sixty-one years for males and sixty-four years for females.62 A senior citizen today, however, can expect to live eighteen to twenty years longer. The downside is that he or she also should expect to die more slowly. The two most common causes of death in 1935 America were respiratory diseases (pneumonia and influenza) and infectious diarrhea, both of which kill rapidly. In contrast, the two most common causes of death in 2007 America were heart disease and cancer (each accounted for about 25 percent of total deaths). Some heart attack victims die within minutes or hours, but most elderly people with heart disease survive for years while coping with complications such as high blood pressure, congestive heart failure, general weakness, and peripheral vascular disease. Many cancer patients also remain alive for several years following their diagnosis because of chemo-therapy, radiation, surgery, and other treatments. In addition, many of the other leading causes of death today are chronic illnesses such as asthma, Alzheimer’s, type 2 diabetes, and kidney disease, and there has been an upsurge in the occurrence of nonfatal but chronic illnesses such as osteoarthritis, gout, dementia, and hearing loss.63 Altogether, the growing prevalence of chronic illness among middle-aged and elderly individuals is contributing to a health-care crisis because the children born during the post–World War II baby boom are now entering old age, and an unprecedented percentage of them are suffering from lingering, disabling, and costly diseases. The term epidemiologists coined for this phenomenon is the “extension of morbidity.”
“We have much to learn about myopia, but two facts are clear. First, myopia is a formerly rare evolutionary mismatch that is exacerbated by modern environments. Second, even though we don’t entirely understand which factors cause children’s eyeballs to elongate too much, we do know how to treat the symptoms of myopia effectively with eyeglasses. Eyeglasses”
“The Good News: Taller, Longer-Lived, and Healthier Bodies The last 150 years have profoundly transformed how we eat, work, travel, fight disease, keep clean, and even sleep. It is as if the human species had a total makeover: our daily lives would be barely comprehensible to our ancestors from just a few generations ago, but we are essentially identical genetically, anatomically, and physiologically. The change has been so rapid that too little time has elapsed for more than a modicum of natural selection to have occurred.”
“Human evolution is not over, but the chances of natural selection adapting our species in dramatic, major ways to common non-infectious mismatch diseases are remote unless conditions change dramatically. One reason is that many of these diseases have little to no effect on fertility. Type 2 diabetes, for example, generally develops after people have reproduced, and even then, it is highly manageable for many years.8 Another consideration is that natural selection can act only on variations that affect reproductive success and that are also genetically passed from parent to offspring. Some obesity-related illnesses can hinder reproductive function, but these problems have strong environmental causes.9 Finally, although culture sometimes spurs selection, it is also a powerful buffer. Every year new products and therapies are being developed that allow people with common mismatch diseases to cope better with their symptoms. Whatever selection is operating is probably occurring at a pace too slow to measure in our lifetimes.”
“study of thirty thousand elderly people in fifty-two countries found that switching to an overall healthy lifestyle—eating a diet rich in fruits and vegetables, not smoking, exercising moderately, and not drinking too much alcohol—lowered heart disease rates by approximately 50 percent.14 Reducing exposure to carcinogens, such as tobacco and sodium nitrite, have been shown to decrease the incidence of lung and stomach cancers, and it is likely (more evidence is needed) that lowering exposures to other known carcinogens, such as benzene and formaldehyde, will reduce the incidence of other cancers. Prevention really is the most powerful medicine, but we as a species consistently lack the political or psychological will to act preventively in our own best interests. It is worthwhile to ask to what extent efforts to treat the symptoms of common mismatch diseases have the effect of promoting dysevolution by taking attention and resources away from prevention. On an individual level, am I more likely to eat unhealthy foods and exercise insufficiently if I know I’ll have access to medical care to treat the symptoms of the diseases these choices cause many years later? More broadly within our society, is the money we allocate to treating diseases coming at the expense of money to prevent them?”
“no matter how you look at the issue, prevention is a fundamentally preferable and more cost-effective way to promote health and longevity. Most people agree that we invest insufficiently in prevention, but they would also surmise that it is difficult to get young, healthy people to avoid behaviors that increase their risk of future illness. Consider smoking, which causes more preventable deaths than any major risk factor (the other big ones being physical inactivity, poor diet, and alcohol abuse). After prolonged legal battles, public health efforts to discourage smoking have managed to halve the percentage of Americans who smoke since the 1950s.19 Yet 20 percent of Americans still smoke, causing 443,000 premature deaths in 2011 at a direct cost of $96 billion per year. Likewise, most Americans know they should be physically active and eat a healthy diet, yet only 20 percent of Americans meet the government’s recommendations for physical activity, and fewer than 20 percent meet government dietary guidelines.20 There are many, diverse reasons we are bad at persuading, nudging, or otherwise encouraging people to use their bodies more as they evolved to be used (more on this later), but one contributing factor could be that we are still following in the footsteps of the marquis de Condorcet, waiting for the next promised breakthrough. Scared of death and hopeful about science, we spend billions of dollars trying to figure out how to regrow diseased organs, hunting for new drugs, and designing artifical body parts to replace the ones we wear out. I am in no way suggesting that we cease investing in these and other areas. Quite the contrary: let’s spend more! But let’s not do so in a way that promotes the pernicious feedback loop of just treating mismatch diseases rather than preventing them. In practical”
“Another relevant factor is money. In the United States and many other countries, health care is partly a for-profit industry.21 Consequently, there is a strong incentive to invest in or promote treatments such as antacids and orthotics that alleviate the symptoms of diseases and that people have to buy frequently and for many years. Another way to make lots of money is to favor costly procedures like surgery instead of less expensive preventive treatments like physical therapy. Preventive”
Daniel E. Lieberman
- Date of birth: June 03, 1964
- Born: in Massachusetts, The United States.
- Description: Daniel E. Lieberman (born June 3, 1964) is a paleoanthropologist at Harvard University, where he is the Edwin M Lerner II Professor of Biological Sciences, and chair of the Department of Human Evolutionary Biology. He is best known for his research on the evolution of the human head and the evolution of the human body.
Lieberman was educated at Harvard University, where he obtained his A.B., M.A. and Ph.D. degrees. He also received a M. Phil from Cambridge University. He was a Junior Fellow in the Harvard Society of Fellows and taught at Rutgers University and the George Washington University before becoming a professor at Harvard University in 2001. He is on the curatorial board of the Peabody Museum of Archaeology and Ethnology, a member of the Department of Organismic and Evolutionary Biology at Harvard, and the Scientific Executive Committee of the L.S.B. Leakey Foundation. He is the director of the Skeletal Biology Laboratory at Harvard University.
Lieberman studies how and why the human body is the way it is. His research combines paleontology, anatomy, physiology and experimental biomechanics in the lab and in the field. He has focused to a large extent on why and how humans have such unusual heads. He is also well known for his research on the evolution of human locomotion including whether the first hominins were bipeds, why bipedalism evolved, the biomechanical challenges of pregnancy in females, how locomotion affects skeletal function and, most especially, the evolution of running. His 2004 paper with Dennis Bramble, “Endurance Running and the Evolution of the Genus Homo” proposed that humans evolved to run long distances to scavenge and hunt. His research on running in general, especially barefoot running was popularized in Chris McDougall’s best-selling book Born to Run. Lieberman is an avid marathon runner, often barefoot, which has earned him the nickname, The Barefoot Professor.