The Seychelles warbler is a once-endangered bird that believes in the proverb, “It takes a village to raise a child.” Warblers often pitch in to help raise others' offspring, and we've now learned this help in trying times helps the mothers, but not the fathers, live longer. The scientists who discovered this think the conclusion is likely to be relevant to other collectively breeding species, humans included.

The value of childcare has become a new political battleground with Senator Elizabeth Warren making a plan for universal health care a centerpiece of her campaign for president. Among the extensive list of benefits she argues the idea could bring, longer life expectancy for parents is not listed, but perhaps this is an oversight. Granted, before making that claim we should have evidence from humans, but it might at least be something worth investigating.

During 15 years studying warblers on the Seychelles island of Cousin, Professor David Richardson measured the health of the birds' DNA by checking the length of their telomeres, the repetitive DNA at the ends of chromosomes that protect them from damage.

"Our previous work has shown that telomere length can be a good indicator of an individual's biological condition relative to its actual age,” Richardson said in a statement. 

Many, but not all, warbler parents get help from other birds to incubate their eggs and feed their young. Two-thirds of the assisting birds are female, often older daughters, including some that are raising their own young at the same time.

In Nature Communications Richardson reports female birds who get assistance have longer telomeres and are less likely to die within a year than those who struggle on alone. The males don't show the same benefit, perhaps because they invest less in raising their offspring.

Without this assistance, older mothers were less able to successfully raise their offspring.

The breeding behavior of a bird you've probably never heard of may appear irrelevant, but Richardson noted; "There is huge variation in lifespan between different species, and also between individuals within a species. But we know very little about ... why individuals in one species live much longer than individuals in another similar species.”

Even before modern medicine, humans had unusually long lifespans for mammals. Richardson thinks our evolution of collective child-raising may have contributed.

The 20th-century shift towards isolated parentage has not been detrimental enough to outweigh the benefits of vaccinations, antibiotics, and clean drinking water, but that doesn't mean it had no effect at all. With children increasingly raised far from the extended family, and grandparents much older than in previous generations, family-based solutions are unlikely, increasing the importance of affordable childcare for parents' sanity, if not their survival.