Ends to a means
نویسنده
چکیده
Most of the familiar garden birds we see all the time have a very short life: just a few years for the commoner species. But some birds have the potential for a very long life and a new study has looked at chromosomal status that may be linked with longevity. A team of international scientists headed by Pat Monahan at the University of Glasgow report, in Proceedings B of the Royal Society (published online), studies on two long-lived species: the European shag and the wandering albatross. They took blood samples from the birds and then analysed their telomeres, the specific nucleotide repeats that cap eukaryotic chromosomes, where shortening is thought to be important in cellular and organismic senescence. Recent studies in birds have examined telomere length as a potential marker of individual age and in relation to interspecific variation in lifespan. Older birds have been shown to display shorter blood cell telomeres in the domestic chicken, zebra finch, tree swallow, Adelie penguin and common tern. Although the team observed the same broad trend of age-related telomere loss as reported for several other bird species, they found that the most dramatic telomere shortening occurs between the chick stage and adulthood in both species, but amongst adults, telomere length was not clearly related to age. They found high inter-individual variation in the magnitude of telomere loss with age, much of it linked to circumstances during growth. This suggests that factors early in life may be a key to telomere loss and longevity in these birds with a potentially long lifespan. Ageing clues: In many species of birds shortening of the telomeres has been linked with ageing but a new study suggests that in two potentially long-lived species, including the wandering albatross, the most dramatic changes occur between the chick stage and adulthood. (Photo courtesy of Photolibrary.com.)
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عنوان ژورنال:
- Current Biology
دوره 14 شماره
صفحات -
تاریخ انتشار 2004