AGEING PARENTS PROVIDE FLAWS
Older mothers and fathers are not only unlikely to win the parents’ race at school sports day. They also put their offspring at a genetic disadvantage, and new research on Alpine swifts suggests why.
It’s well known that offspring born to elderly parents are at a higher risk of genetic damage. As animals age, their telomeres – tiny caps that protect the vulnerable ends of chromosomes [see The Explainer on p15] – get shorter and less effective, and that length is passed on to offspring.
What’s less clear is whether short telomeres are inherited directly from older parents or a product of a poor upbringing (telomeres also get shorter under stress).
For Alpine swifts, it seems it’s a complex blend of both. Older fathers cared for their offspring
just as well as younger ones, suggesting that telomere length is inherited with the sperm.
The quality of maternal care does play a role too, though – chicks raised by an adoptive (unrelated) older female also developed short telomeres. It’s a double whammy that means lower life expectancy for individuals whose parents are past their best.