The long and short of a bird’s life may be recorded in the tips of its chromosomes, a new study suggests.
A study of Seychelles warblers living on a small island in the Indian Ocean suggests that the length of telomeres — bits of DNA that cap chromosome ends — can predict a bird’s chance of dying better than its chronological age can. Warblers with shorter telomeres were less likely to survive another year, especially if the truncation happened rapidly, David S. Richardson, a molecular ecologist at the University of East Anglia in Norwich, England, and colleagues report online November 20 inMolecular Ecology.
The study “provides very important evidence that backs up what has been found in the laboratory — changes in telomere length matter a lot,” says animal ecologist Pat Monaghan of the University of Glasgow in Scotland.
Increasing age and body mass were also linked to shorter telomeres in the birds. That result stands in contrast to a recent large study of people in northern California that found telomeres get shorter with age, but that higher body mass is associated with longer telomeres (SN Online, 11/11/12).
Like shoestring aglets, telomeres stop chromosomes from unraveling or being eaten away at the ends. Cells with very short telomeres become decrepit or die, but it has been unclear whether that has any effect on whole body.