In recent years, the trend of male sexual reproduction has aroused great concern and extensive discussion among European and American scientists. Some people even ask: will mankind face the crisis of extinction? What's wrong with men's sperm? . It is shocking to worry that human beings will become endangered species, but judging from the analysis results of sperm evolution in the past 50 years by medical experts in Europe and North America, the future is not optimistic. Alfred Spiha, the epidemiologist and chairman of the French Institute of Public Health (IRESP), recently put forward a remarkable conclusion: human beings are facing the danger of declining reproductive rate. The important sign is that the sperm emission of men living in modern industrialized countries is reduced by half compared with that of their parents and grandparents.