Dolphins age more slowly with a little help from their friends

"While these delightful bonds may seem fleeting, a subset of dolphins form complex alliances based on strong, lifelong friendships. And these bonds may slow aging, a recent study suggests. To explore that association, researchers drew on more than four decades of behavioral observations of a well-studied group of Indo-Pacific bottlenose dolphins in Shark Bay, Australia. The new research showed that social relationships influenced the pace of biological aging in the dolphins."

"Among these dolphins, males with close social bonds spend much of their time together, often traveling, foraging, mating and resting in the same groups. Within the Shark Bay population, the researchers focused on 38 male dolphins with precisely known chronological ages. The team collected skin samples from the dolphins to measure DNA methylation patternsbiochemical modifications that determine which genes are activatedin order to estimate their biological ages."

"The main clock that was used in the study was a version that the team calibrated specifically for the Shark Bay dolphin population to measure regular changes in chemical markers on DNA that accumulate over the course of a lifetime. Aging is a complex process that includes DNA damage [such as] double-strand DNA breaksit's not just the mitochondria working faster or being exhausted or suddenly having a lot of mutations, says the study's lead author Livia Gerber."

Indo-Pacific bottlenose dolphins in Shark Bay form lifelong, complex alliances, with male companions spending extended time traveling, foraging, mating and resting together. Researchers analyzed over four decades of behavioral observations and focused on 38 males with precisely known chronological ages. Skin samples were collected to measure DNA methylation patterns, biochemical modifications that influence gene activation, and multiple epigenetic clocks were used to estimate biological age. A population-calibrated epigenetic clock tracked lifetime accumulation of chemical markers on DNA. Strong social bonds among males correlated with a slower pace of biological aging. Aging was framed as a multifaceted process that includes DNA damage such as double-strand breaks.

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