[ti:Do Bats Hold the Secret to Long Life?] [by:www.51voa.com] [00:00.00]更多听力请访问51VOA.COM [00:00.00]Bats are the only mammals that can fly a great distance, [00:05.11]but they have another ability. [00:07.88]Many bats live a very long time for an animal their size. [00:14.88]European researchers are studying bats [00:19.04]to understand why they live so long. [00:22.75]They hope to make discoveries aimed [00:26.77]at fighting the aging process in human beings. [00:31.71]Last week, the group of scientists said [00:36.93]they had identified important biological qualities in some bat species. [00:45.00]The group studied bat chromosomes, [00:49.78]a line of genes found in the nucleus of cells. [00:54.62]The scientists were most interested in structures [00:59.68]connected to the ends of the chromosomes. [01:03.11]They are called telomeres. [01:06.55]Telomeres protect the ends of chromosomes, [01:11.73]which shorten each time a cell divides. [01:16.04]Scientists believe this shortening process causes cells to break down. [01:23.74]They say this is what causes aging. [01:28.24]A report on bats was published this month [01:33.02]in the journal Science Advances. [01:36.26]Among the leaders of the study was Emma Teeling, [01:41.95]a biologist with University College Dublin in Ireland. [01:48.04]Teeling said studying long-living mammals [01:53.50]that have developed ways to fight aging "is an alternative way [01:58.85]to identify the molecular basis of extended ‘health spans.'" [02:06.11]She added that studying bats enables scientists [02:12.38]to learn more about the processes "that drive healthy aging." [02:18.31]The European researchers studied 493 bats from four bat species. [02:28.08]The group used information that had been gathered over more than 60 years. [02:36.16]Of these animals, the greater mouse-eared bat [02:42.32]generally lived the longest, an average of 37 years. [02:48.17]The scientists said this and a related species, [02:54.39]which are grouped together under the name Myotis, [02:58.91]had telomeres that did not shorten with age. [03:03.74]Another Myotis bat holds the record for oldest age, reaching 41 years. [03:14.03]The scientists' findings suggest that these bats' cells [03:21.40]have the ability to maintain and repair their telomeres. [03:27.62]This, they said, helps guard against the aging process. [03:34.04]Based on its body size, a bat like the greater mouse-eared bat [03:41.38]would be expected to live four years. [03:45.07]But, these mammals have been found to live nearly 10 times longer than that. [03:51.81]The scientists found that only 19 species of mammals live longer than humans [04:00.84]when their body size is considered. Eighteen of these are bats. [04:08.13]The only exception is an unusual African rodent, the naked mole rat. [04:16.91]I'm Mario Ritter. 更多听力请访问51VOA.COM