Credit: George Hodan/public domain Across the entire world, women can expect to live longer than men. But why does this occur, and was this always the case? 
 
 According to a new study led by University of Southern California Leonard Davis School of Gerontology researchers, significant differences in life expectancies between the sexes first emerged as recently as the turn of the 20th century. As infectious disease prevention, improved diets and other positive health behaviors were adopted by people born during the 1800s and early 1900s, death rates plummeted, but women began reaping the longevity benefits at a much faster rate. 
 
 In the wake of this massive but uneven decrease in mortality, a review of global data points to heart disease as the culprit behind most of the excess deaths documented in adult men, said USC University Professor and AARP Professor of Gerontology Eileen Crimmins. 
 
 "We were surprised at how the divergence in mortality between men and women, which originated as early as 1870, was concentrated in the 50 to 70 age range and faded out sharply after age 80," Crimmins said. 
 
 The study was conducted with USC University Professor and ARCO/William F. Kieschnick Professor in the Neurobiology of Aging Caleb Finch and Research Associate Hiram Beltrán-Sánchez of the Center for Demography of Health and Aging at the University of Wisconsin-Madison. It examined the lifespans of people born between 1800 and 1935 in 13 developed nations. 
 
 Focusing on mortality in adults over the age of 40, the team found that in individuals born after 1880, female death rates decreased 70 percent faster than those of males. Even when the researchers controlled for smoking-related illnesses, cardiovascular disease appeared to still be the cause of the vast majority of excess deaths in adult men over 40 for the same time period. Surprisingly, smoking accounted for only 30 percent of the difference in mortality between the sexes after 1890, Crimmins said. 
 
 The uneven impact of cardiovascular illness-related deaths on men, especially during middle and early older age, raises the question of whether men and women face different heart disease risks due to inherent biological risks and/or protective factors at different points in their lives, Finch said. 
 
 "Further study could include analysis of diet and exercise activity differences between countries, deeper examination of genetics and biological vulnerability between sexes at the cell level, and the relationship of these findings to brain health at later ages," he said. 
 
 The study, "Twentieth century surge of excess adult male mortality," appears in the Proceedings of the National Academy of Sciences and was supported by the National Institute on Aging. 
 
 Explore further: Women with type 1 diabetes at significantly higher risk of dying compared with men 
 
 More information: Twentieth century surge of excess adult male mortality, www.pnas.org/cgi/doi/10.1073/pnas.1421942112 ||||| A month or so before he died, Alexander Imich, the world’s oldest man, asked a friend, “How long can this go on?” 
 
 The 111 year old—who was born in Poland the year the Wright Brothers first took flight, and survived a stint in a Soviet gulag before immigrating to the United States in 1951—was informed in April that he just became the world’s oldest known living man. In an interview in his New York City apartment, Imich told The New York Times, “I never thought I’d be that old,” though wryly added that it’s “not like it’s the Nobel Prize.” 
 
 Imich only held the title for about a month-and-a-half, however. He died in June, bequeathing the position to Sakari Momoi, a 111-year-old in Japan who was born just a day after Imich, on February 5, 1903. After Imich’s passing, it likely did not take long for the news to reach Momoi. 
 
 “Oh yes, people know if they’re next in line,” says L. Stephen Coles, a lecturer in the Department of Chemistry and Biochemistry at the University of California, Los Angeles, and co-founder of the Gerontology Research Group. Everybody wants to go down in history, he says. 
 
 Since 1990, the Gerontology Research Group has assumed the role of record keepers for the world’s supercentenarians, or persons older than 110. Previously, research groups, individual countries and private hobbyists tracked supercentenarians for studies or for census purposes, or simply out of personal interest. But that information was not compiled into a central, standardized database, and it was largely closed to public viewing. “I thought, this ought to be available online, so everyone can know about it,” Coles says. 
 
 To fill this need, around 15 years ago Coles and his colleagues began publishing their database online. Most attention falls on one list in particular, which they call “Table E.” Neatly filed in chronological order, Table E contains all of the world’s confirmed, still-living supercentenarians. 
 
 In addition to satiating curiosity and providing world-record listings, the Gerontology Research Group’s database also offers scientific insight into the phenomenon of living an exceedingly long life. Expert volunteers with the organization conduct extensive interviews with the people on the list, taking blood samples for DNA analysis from those who are willing. Ultimately, the group’s goal is to use such data to design drugs that will slow down the aging process itself, though such breakthroughs—if even possible—are likely years away. 
 
 The team regularly updates the list, and it usually hovers at just over 70 entries—the vast majority of them women. Misao Okawa, born in 1898, currently stands at the top, at 116 years old. (The longest ever-confirmed lifespan belongs to Jeanne Calment, a French woman who passed away in 1997 at the age of 122.) 
 
 Uncertainty at the top 
 
 Earning a spot on Table E requires more than just living to see 110, however. Supercentenarians must prove that they have indeed reached that milestone. This is because Coles and his colleagues frequently encounter phony claims. “There are a lot of wannabes,” Coles says. “It’s not bad intent necessarily on the part of the individuals who are old, but of their families saying things like ‘Oh, actually he’s 117.’” 
 
 When it comes to age forgery, Coles has seen it all. He recently received a claim from India of an individual who is supposedly 179—a feat that is almost certainly physically impossible. The deceit can be harder to spot, such as the time a man in Turkey tried to pass himself off as his deceased brother, who was ten years older. And in one particularly challenging case, the government of Bolivia issued false documents to a man who was 106, stating that he was 112. 
 
 These problems are well known among those who study the very old. “Ninety-eight percent of ages claimed over 115 are false,” says Thomas Perls, a professor of medicine and geriatrics at Boston Medical Center, and director of the New England Centenarian Study. Based on a research paper he published on the topic, Perls says that “There’s a total of ten different major reasons why people do this.” 
 
 Sometimes, the motivation for lying is monetary. In the U.S., for example, a handful of people inflated their ages in order to claim to be Civil War veterans, giving them access to pensions. Countries and local officials, too, might boast a surplus of centenarians to propagate a “Shangri-La” myth about a particular town or region in an effort to attract tourist dollars. China and Dominica are notorious for this, Perls says. Still others might inflate their ages to validate religious beliefs and recruit followers, such as some swamis from India who say they are 200-plus years old. 
 
 In other cases, a government or group might want to demonstrate that theirs is a “superior race,” Perls continues. In the 1950s, for example, the USSR purported that its citizens enjoyed “unrivaled longevity.” The Soviet government insisted that this was especially true for those hailing from the Caucuses—dictator Joseph Stalin’s birthplace—who were said to regularly live into their 140s and 150s. 
 
 To ensure people are indeed as old as they say they are (or that their families or governments say they are), the Group subjects each applicant to a process Coles calls postulate evaluation. According to the rules, supercentenarian candidates must present two to three pieces of documentation that proves their age. This includes some sort of documentation that dates back to their original year of birth, such as a birth certificate, baptismal record or notation in a book. Secondly, Coles requires a current photo ID issued by an unbiased government agency. Finally, married women who took their husband’s name must produce an additional document proving that the name-change took place. 
 
 For every supercentenarian that the Gerontology Research Group confirms, probably at least one more slips through the cracks. Some families simply prefer to protect their privacy, so they do not reach out to the group. In other cases, the researchers might not have the logistic capacity to investigate every lead. Although the group includes about 40 volunteer correspondents based around the world who are in charge of tracking down supercentenarians in their country or region, sometimes claims prove impossible to follow-up on. For example, Coles recently received an email from a person in Austin stating that two years ago he met a 108-year-old man wearing a funny hat at a local Wal-Mart. “In his email, he said, ‘That man must be 110 years old now, so here’s the address of the Wal-Mart so you can go find him,’” Coles says. “We’re a volunteer organization: we can’t track down those kinds of leads.” 
 
 In other cases, individuals who don’t make the cut likely are genuine supercentenarians, but they are unable to provide the documentation to prove it. While Japan has kept scrupulous birth records for more than a century (perhaps partly explaining why that country has so many supercentenarians per capita), other countries have historically been less meticulous about that task. Due to a general lack of written birth records in African nations, for example, Table E includes no one from that massive continent. Similarly, China certainly has many supercentenarians, but none are confirmed because the Chinese government did not track births prior to the early 1900s. India, likewise, did not keep such records until around 1903, when the British began tracking some births there—especially of eldest sons in landowner families. As a result, Coles expects that more and more Indians will join the list as years pass. 
 
 For all of these reasons, Coles suspects that the world’s true number of supercentenarians is likely about double what’s contained in Table E, probably hovering at around 150. And it also means that when news wires report the death of “the world’s oldest person,” they may not always be accurate. 
 
 Heritable longevity 
 
 For now, very few make it to 110. “The probability of getting to be a supercentenarian is about one in seven million,” Coles says, and living beyond that milestone is even more exceptional. A 110-year-old’s odds of seeing her 111th birthday is about 50-50, meaning that living to 113, 114 or 115 is like getting three, four or five heads in a row in a coin toss. 
 
 This, of course, leads to the burning question: how do those who make it to 110 and beyond manage that feat? 
 
 The short answer is that we do not know. Supercentenarians come from diverse occupations and social backgrounds. Some drink and smoke, while others abstain from the partying lifestyle; some are religious, others atheists; some have rich networks of family and friends, others are virtually on their own. While centenarians tend to cluster in Sardinia, Italy, and Okinawa, Japan, supercentenarians, on the other hand, have no significant association with any particular geographic area. 
 
 “I’ve interviewed more supercentenarians than probably anyone else, trying to find out what they have in common,” Coles says. “The answer is almost nothing.” 
 
 But as both Coles’ and Perls’ studies on supercentenarians confirm, the one thing that nearly all supercentenarians do have in common is that they have a history of long-lived close relatives. Unlike average longevity, extreme longevity, it seems, largely comes down to genes. “Aging,” Perls says, “is an incredibly heterogeneous trait.” 
 
 As he explains, things like diet, exercise, lifestyle and healthcare seem to play a huge role in whether or not someone makes it to their 80s, but by the time they reach their 90s and beyond, those factors become less important. “About 70 percent of average aging is in your hands with health-related behaviors,” Perls says. “But if you get beyond 100, the tables turn and it’s more like 70 percent genetic and 30 percent behaviors.” Women, too, have an obvious edge in this process—female supercentenarians outnumber males about ten-to-one—although scientists have not figured out just why this is so. 
 
 Bernice Mason, a 105-year-old woman living in Downey, California, perfectly fits this model, though her journey into extreme longevity came as a surprise. “I had no idea that I’d be around now,” she says. “I don’t think I’d ever cherished the idea, or even gave it a thought. It was an unknown concept in our circle of friends.” 
 
 Mason’s mother lived to be 92, however, and one of her grandfathers lived into his late 90s. Her older sister, now 107, is still going strong, too, and recently talked Mason into joining Perls’ New England Centenarian Study. “We can’t see each other any more because she lives in Arizona and neither of us are able to travel,” Mason says. “But we talk on the phone quite often.” 
 
 As for whether she’ll make it onto Table E, Mason has no idea. “It’s the Lord’s will,” she says. ||||| When it comes to smarts, women are catching up to men in some areas and outpacing them in others, new research has found. 
 
 In particular, women, on average, are better than men at so-called episodic memory, which involves recalling and describing experiences and facts, while men's edge over women in numerical abilities has narrowed somewhat. The findings were drawn from a large study of older people from 13 different European countries. 
 
 Overall, humans have gotten smarter through time. That cognitive leap is thanks largely to better health, education and living conditions, the new study finds. 
 
 "When living conditions increase over time, so do cognitive abilities both for men and women, and that has been shown previously," said study co-author Agneta Herlitz, a psychologist at the Karolinska Institutet in Sweden. "But we show that women's cognitive abilities increase more than men's." 
 
 Culture or nature? 
 
 Long before Teen Talk Barbie said the words "math is hard," people have debated whether average gender differences in cognition are innate, the product of a sexist society or a little of both. [Busted! 6 Gender Myths in the Bedroom and Beyond] 
 
 Studies have consistently shown differences between the average cognitive abilities of men and women. Dozens of studies have found men are, on average, better able to rotate objects in their minds, whereas women do better on tasks associated with episodic memory, meaning they can better recall lists of words or objects. 
 
 And a 2013 study in the journal Proceedings of the National Academy of Sciences found that men's and women's brains tend to be wired very differently. An average woman's brain, that study revealed, has more connections between hemispheres, while a man's noggin has more connections within hemispheres. The study researchers speculated that this may make the male brain better at motor skills and the female brain better at combining analytical and intuitive thinking. 
 
 But culture clearly plays a big role in creating differences in cognition. Women have historically had fewer educational opportunities. And even when education levels are equal, women may face negative stereotypes. For instance, teachers tend to underrate women's math abilities, even when they perform such skills just as well as men, according to a 2012 study published in the journal Gender & Society. And in more-egalitarian societies, there's a smaller gap in mathematical abilities. 
 
 Small differences 
 
 The researchers looked at data from 2006 to 2007 in the Survey of Health, Aging and Retirement in Europe, which included 31,000 men and women who were born between 1923 and 1957 in 13 different European countries. The researchers compared older and younger groups to show how cognition has changed over time. 
 
 As part of the study, researchers tested the older adults' episodic memory by asking them to memorize and recall a list of 10 words. The participants also had to name as many different animals as they could in a minute, a task that tests an ability known as category fluency. Finally, the survey tested numeracy, or number sense, with word problems such as: A secondhand car dealer is selling a car for $6,000. This is two-thirds of what it costs new. How much did it cost new? (The answer is $9,000.) [Why You Forget: 5 Strange Facts About Memory] 
 
 Across all the cultures, younger people performed better than older participants. People from the northern countries also did better on average than those in Southern and Central Europe, the researchers wrote in the paper, which was published today (July 28) in the journal Proceedings of the National Academy of Sciences. 
 
 Women in Northern Europe outperformed men in their recall ability, whereas in Central and Southern Europe, only women from the younger cohorts showed this advantage. 
 
 Men outperformed women in the math questions in all regions, though the margin narrowed over time. The math gap between the sexes was much greater for people in Central and Southern Europe. Men and women performed equally well at category fluency in Northern Europe, and women caught up with men for later cohorts in Central Europe. 
 
 Though everyone saw improvements over time, the women did so more dramatically. The gains in smarts coincided with better living conditions, as measured by gross domestic product (GDP), fertility rate, health indicators such as mortality rate, and educational opportunities, the researchers found. 
 
 Differences not eliminated 
 
 Because women's better performance coincided with higher levels of societal development across different regions and cohorts, the results suggest that improved living conditions have benefited women more than men. But the scientists aren't sure whether that trend will continue into the future, as women simply may be "catching up" after starting from further behind, Herlitz said. 
 
 There may be sex-specific differences in cognitive improvements with better living conditions, said David Geary, an evolutionary psychologist at the University of Missouri, who was not involved in the study. However, "I don't believe, as they argue, that girls and women will improve more than boys and men across the board. But they will gain more in some domains, including episodic memory, whereas boys and men will gain more in others," Geary told Live Science in an email. 
 
 Some small cognitive differences between the sexes will likely persist in the future, but for the most part, men and women's cognitive abilities overlap, said Diane Halpern, the dean of the College of Social Sciences at the Minerva Schools at Keck Graduate Institute in Claremont, California, and the author of "Sex Differences in Cognitive Abilities" (Taylor and Francis, 2000). 
 
 The cause for the differences can't be pinpointed to either hard-wired biological differences or cultural factors, Halpern, who was not involved in the study, told Live Science. 
 
 "It's not nature or nurture. It's not evolution or culture. It's really some interaction of all those variables," Halpern said. 
 
 Follow Tia Ghose on Twitter and Google+. Follow Live Science @livescience, Facebook & Google+. Original article on Live Science.
– There's a reason we don't typically call Earth's oldest person the oldest woman in the world—the oldest person is pretty much always a woman. In fact, just two of the world's 53 living supercentenarians (people 110 and older) are men, reports IFL Science. But why is the longevity gap so stark, and how long has it been so? An international team of researchers is investigating the lifespans of men and women born between 1800 and 1935 in 13 developed nations in search of answers, reports PhysOrg, and they've found that women's superior longevity only emerged recently. Before 1840, death rates were very similar between men and women. But since those rates began to plummet in 1880 thanks in large part to improved diets, vaccinations, and better health care, female death rates have dropped 70% faster than male ones, and heart disease seems to be holding men back the most, the researchers report in Proceedings of the National Academy of Sciences. Men may be more biologically susceptible to cardiovascular health problems, and their different weight distribution could play a role here, reports Live Science. The researchers plan to further explore the differences between male and female biology, genetics, and lifestyles to look for answers. (The oldest man in the US says his trick has been to enjoy a can of beer a day.)