longevity

Teeth from the upper jaw of a child (the Xujiayao child) of about 6 and a half, who died between 100,000-200,000 years ago were examined by X-ray: But the ancient child’s overall dental growth and development falls within the range observed among kids today, paleoanthropologist Song Xing of the Chinese Academy of Sciences in Beijing and her colleagues report online January 16 in Science Advances. That humanlike rate of dental development suggests that the youngster belonged to an East Asian Homo population with a relatively long life span and an extended period of child care, the researchers speculate. Those characteristics are associated with present-day humans’ lengthy period of tooth growth.Bruce Bower, “An ancient child from East Asia grew teeth like Read More ›

Remember the story earlier this year about the anomalous plateau found in the human lifespan, such that “after the age of 105, human mortality seems to hit a plateau. That is, you aren’t any more likely to die at 110 than at 105”? It’s been challenged by a study in PLOS Biology which suggests that the finding may be an artifact of errors in record-keeping re births and deaths: Age-recording errors can theoretically lead to plateaus in very old ages, Newman and other demographers have suggested, because at those extreme ages, most people with age underestimation errors have already died, meaning that people with age overestimation errors—whose mortality rates correspond to their true, younger ages—make up a greater and greater proportion Read More ›

It’s now suggested that people likely to live long tend to find each other (assortative mating). How else to explain this?Researchers found that siblings’ and first cousins’ lifespans were well correlated but also: But spouses’ lifespans were correlated, too. That could be easily explained by spouses sharing the same household and lifestyle: eating the same healthy diet or puffing on cigarettes together. But the researchers noticed something odd: the lifespans of other relatives related only by marriage also correlated. That can’t be explained by genes, and it can’t be explained by shared environment. So Ruby and his colleagues started investigating the lifespans of in-laws. They looked at siblings-in-law, and first-cousins-in-law, and then further afield, at relationships like “the sibling of Read More ›

This group somehow links it to natural selection: A new USC Dornsife study indicates that aging may have originated at the very beginning of the evolution of life, at the same time as the evolution of the first genes. … This could be a game changer for research on longevity and aging. It may also be relevant to the scientific discussions surrounding CRISPR9 gene editing,” said John Tower, biologist at the USC Dornsife College of Letters, Arts and Sciences. “We found that when it comes to genes, aging may not always be a negative trait. It may help an organism survive.” To test this, Tower and a team of researchers developed a scenario with molecules can replicate themselves. Such molecules Read More ›

Human lifespans have not changed over the millennia: People in the past were not all dead by 30. Ancient documents confirm this. In the 24th century B.C., the Egyptian Vizier Ptahhotep wrote verses about the disintegrations of old age. The ancient Greeks classed old age among the divine curses, and their tombstones attest to survival well past 80 years. Ancient artworks and figurines also depict elderly people: stooped, flabby, wrinkled. Hunter-gatherers today have a normal lifespan of about 70 years too, of course, but hardships reduce the likelihood that a given person will reach that age. The maximum human lifespan (approximately 125 years) has barely changed since we arrived. It is estimated that if the three main causes of death Read More ›

From Chuck Dinerstein at American Council for Science and Health: There is increasing evidence that a correlation exists between a person’s social support and engagement and their longevity. At a bare minimum, it makes sense because it is challenging to manage chronic disease or recovery from hospitalization on your own. A new study looks at religious participation as a marker for that social integration and to avoid the bias of self-reported religious activity; the researchers measured religious involvement noted in obituaries. (Of course, they might also have induced a bit of bias on the report of grieving family members writing those obituaries) There is a clear link between attendance at religious services and social support, even the number of close Read More ›