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Why large dogs age faster than small ones, and other October research highlights
Plus invisible tattoos, medieval skeleton gets an ID, trapping a single antimatter particle, and more.
It’s a regrettable reality that there is never enough time to cover all the interesting scientific stories we come across. So every month, we highlight a handful of the best stories that nearly slipped through the cracks. October’s list includes an epigenetic mechanism for why large dogs age faster than smaller ones; physicists who trapped a single particle of antimatter for months; and invisible tattoo inks that only show up under UV light.
In many mammalian species, larger creatures tend to have longer lifespans. Mice, for instance, live an average of just two years, while some whales can last for as long as 200 years. Dogs, however, buck this pattern; larger dogs tend to age faster and die younger than smaller ones, which makes canines an ideal model for biologists to study to learn more about aging in general. Arizona State University scientists report that these lifespan differences seem to be due to so-called “jumping genes,” according to a paper published in the journal Science.
The authors used data from 864 dogs collected in the Dog Aging Project to map patterns of DNA methylation (which influences how much certain genes are turned on or off) across the entire genome. It’s part of the epigenome, whose markers can change over time in response to stress and other environmental factors. Genetic sequences, by contrast, are largely fixed. So DNA methylation is a good chemical indicator of aging and DNA regulation.
Their analysis showed that aging in dogs is linked to the decrease in the regulation provided by DNA methylation, particularly in regions where there are “jumping genes” that can move from chromosome to chromosome. These jumps can damage DNA, causing cancer and other age-related diseases, and their activity increases with the loss of regulatory markers. The authors identified a specific class of jumping genes called LINE1s that were responsible for the different rates of aging in dogs. Giant dog breeds lost roughly 35 percent more LINE1 methylation each year compared to small breeds.
“This is one of the clearest molecular signatures we’ve seen that aligns with the well-known size-lifespan trade-off in dogs,” said co-author Blaise Mariner. “It suggests that faster aging in larger dogs may be driven, at least in part, by reduced control over these jumping genes.”
Science, 2026. DOI: 10.1126/science.aeb2986 (About DOIs).
One of the biggest unanswered questions in cosmology is why the early universe had a fundamental asymmetry between matter and antimatter. When matter and antimatter particles collide, they annihilate into energy, so that asymmetry resulted in matter dominating our universe, which contains much more matter than antimatter. It’s extremely difficult to create and isolate antimatter, requiring special traps. Physicists at Northwestern University have succeeded in trapping a single positron (antimatter particle) for months on end, according to a paper published in Physical Review Letters.
Co-author Gerald Gabrielse and his team built on earlier work, in which they trapped a single electron to create a one-electron quantum cyclotron. They then used the setup to make one of the most precise measurements of its magnetic moment yet. Trapping a positron was a bit trickier. They harvested the positron from sodium-22 nuclei, slowing it down enough to guide it into a near-perfect vacuum trap of electric and magnetic fields. Once inside, they chilled the positron to just 300 millikelvins (0.3° above absolute zero), thereby keeping the positron in its quantum ground state. They found they could maintain that state for months at a time.
That enabled Gabrielse et al. to manipulate and detect the particle’s individual quantum energy state using tuned microwaves—the first critical step in being able to measure the positron’s magnetic properties, hopefully with the same precision they achieved in their earli