How old are you? Usually we calculate according to the calendar, starting from the time of birth, how long we have lived so far. However, this kind of actual age does not necessarily reflect a person’s biological age. After all, heredity, nutrition, infection, stress and other factors will make the aging rate vary from person to person, and the degree of “aging” varies from person to person. < / P > < p > in order to more accurately measure a person’s aging and weakness, scientists have developed some methods, such as measuring muscle strength or gait, comparing telomere length of chromosomes, and so on. Scientists who study aging hope that eventually a comprehensive set of indicators to measure “aging” can not only predict how long a person can live healthily, but also help clarify which factors lead to aging related diseases and which methods can prolong life. < p > < p > Professor David Sinclair of Harvard University is a well-known scientist in the field of anti-aging, and his research team has recently taken a step towards this goal. Using artificial intelligence, they have developed two “life clocks” that can measure the physiological age of mice and predict how long aging mice can live. < / P > < p > in this work, the team followed the health of 60 mice for more than a year, from 21 months until natural death. The researchers said it was the first study to track the decline in mice over a lifetime. < / P > < p > every six weeks, the researchers conducted a “physical examination” of mice, including walking ability, hunchback, hearing and vision. These indicators are also commonly used to measure the degree of human aging. < p > < p >} from the hair, gait, bone morphology and other aspects, we can see that the old mice on the left are weaker. Reference materials [2]; Credit: Alice Kane < / P > < p > then, using artificial intelligence, the researchers trained two computer models to learn the physical examination data of mice. One model, called fright, infers how old the mice are from the degree of weakness. Another model, called afraid, is more like a life countdown clock, predicting the remaining life span of aging mice. Using afraid, researchers can predict the life expectancy of mice up to a year in advance – the equivalent of a third of “rat birth” ahead of time – within two months. < / P > < p > the researchers said they named the two models because aging and death are often frightening. “Many aspects of aging are really frightening, but we hope to find ways to delay aging, and even rejuvenate, so that we can stay young for a longer period of time.” One of the main authors of the study, Dr. Michael Schultz, said. < / P > < p > scientists point out that such life clocks can help accelerate the discovery of longevity genes and ways to delay aging. “Usually, it takes up to three years to study whether a drug or dietary intervention can slow aging, even in mice.” Alice E. “With predictive biometric technology, we can more quickly confirm whether interventions are working,” Dr. Kane said < / P > < p > of course, there are great differences in physiology between mice and humans, and the impact of behavioral, environmental and social factors on human health is obviously much more complex. Therefore, these two “life clocks” can not be used to predict human health, physiological age and life span. < / P > < p > but the researchers believe that, in principle, human frailty indicators can also be used to develop “life countdown” clocks such as afaraid, “provided there is such a data set, which tracks from 60 to 90 years old, and has important mortality follow-up data.” “As far as we know, there is no such large longitudinal data set yet,” Dr. Schultz said < / P > < p > what would you do if you had such a life clock that could accurately predict people’s health and life expectancy? Maybe we have the opportunity to change bad lifestyle earlier, or to use drug intervention, so as to get a longer healthy life. It is said that “gta5” will be launched on Google cloud game platform stadia