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A 120-y time series of genomes reveals the consequences of closed breeding in German Shepherd Dogs

Proceedings of the National Academy of Sciences, Volume 122, Issue 48, December 2025. SignificanceBy analyzing historical genomes of German Shepherd Dogs (GSDs) from throughout the 20th century, we showed that population declines during the Second World War and the use of popular sires led to the progressive loss of genetic diversity and …

Woodlands of Antiquity: A millennium of dendrochronological data on forest exploitation and timber economy between the Alps and the Atlantic

Proceedings of the National Academy of Sciences, Volume 122, Issue 48, December 2025. SignificanceThis study presents empirical evidence of the deforestation driven by the Roman Empire north of the Alps and offers a unique, robust, and high-resolution dataset to explore woodland exploitation across a full millennium. By analyzing timber, …

Variability of annual polar motion and its relationship to the Chandler wobble

Proceedings of the National Academy of Sciences, Volume 122, Issue 48, December 2025. SignificanceFor nearly a century, continuing to the present, a complete accounting of the excitation of the Chandler wobble (CW), a resonant motion of Earth’s rotation axis, has been a major scientific goal. We identify episodes of a near six-year …

Large drainage systems produced half of Mars’ ancient river sediment

Proceedings of the National Academy of Sciences, Volume 122, Issue 48, December 2025. SignificanceRivers on Earth are large and dynamic systems that diversify ecosystems through interactions between climate and tectonics. Here, we show that even in the absence of plate tectonics on Mars, large drainage systems existed; however, they are …

Gray wolves in an anthropogenic context on a small island in prehistoric Scandinavia

Proceedings of the National Academy of Sciences, Volume 122, Issue 48, December 2025. SignificanceWolves, the wild ancestor of dogs, are the only large carnivores that have undergone domestication by humans. Yet, it remains unclear if this process took place via direct and deliberate human control of wild wolves or if wolf populations …

A quantitative risk assessment framework for mortality due to macroplastic ingestion in seabirds, marine mammals, and sea turtles

Proceedings of the National Academy of Sciences, Volume 122, Issue 48, December 2025. SignificancePlastic ingestion is a known cause of mortality across taxa, yet the quantitative risk plastic ingestion poses is still poorly understood. Based on data from more than 10,000 necropsies, we estimate the likelihood of mortality due to the …

Evidence of an enhanced near-surface ozone layer at tropical latitudes on Mars

Proceedings of the National Academy of Sciences, Volume 122, Issue 48, December 2025. SignificanceOzone plays a key role in both atmospheric and near-surface chemistry, as well as in UV absorption in planetary atmospheres. We report observations of ozone from the surface of another planet using the ozone detector aboard NASA’s Mars 2020 …

The first preserved nasal cavity in the human fossil record: The Neanderthal from Altamura

Proceedings of the National Academy of Sciences, Volume 122, Issue 48, December 2025. SignificanceNeanderthals are the subject of an enduring debate regarding possible nasal adaptations and their impact on craniofacial morphology. Yet, this debate has been strongly influenced by the lack of a preserved nasal cavity in the human fossil …

How public involvement can improve the science of AI

Proceedings of the National Academy of Sciences, Volume 122, Issue 48, December 2025. As AI systems from decision-making algorithms to generative AI are deployed more widely, computer scientists and social scientists alike are being called on to provide trustworthy quantitative evaluations of AI safety and reliability. These calls have …

Female fertility and infant survivorship increase following lethal intergroup aggression and territorial expansion in wild chimpanzees

Proceedings of the National Academy of Sciences, Volume 122, Issue 47, November 2025. Lethal coalitionary intergroup aggression is a conspicuous aspect of wild chimpanzee behavior. Evidence indicates that such violence can lead to territorial expansion, but whether this results in fitness benefits is unknown. Here, we show that female …

Object continuity through invisible retinal motion at saccadic speed

Proceedings of the National Academy of Sciences, Volume 122, Issue 47, November 2025. Saccadic eye movements rapidly shift the visual scene across the retina, raising the question of how object correspondence is established between gaze fixations. Using submillisecond video projection, we isolated the role of high-speed retinal motion from …

Marine heatwave decimates fire coral populations in the Caribbean

Proceedings of the National Academy of Sciences, Volume 122, Issue 47, November 2025. Marine heatwaves (MHW) are common destructive events affecting coral reefs. After decades of degradation, the shallow reefs of the United States Virgin Islands have been depleted of scleractinian corals, leaving abundant colonies of the hydrozoan fire …

Interactions between long- and short-term synaptic plasticity transform temporal neural representations into spatial

Proceedings of the National Academy of Sciences, Volume 122, Issue 47, November 2025. SignificanceNeurons in the brain communicate through spikes that are transmitted via chemical synapses that express both long-term and short-term plasticity. While long-term plasticity is thought to be the central site of learning and memory and has …

The potential existential threat of large language models to online survey research

Proceedings of the National Academy of Sciences, Volume 122, Issue 47, November 2025. SignificanceSurveys are a primary source of data across the sciences, from medicine to economics. I demonstrate that the assumption that logically coherent responses are from humans is now untenable. I show that autonomous AI agents, operating from a …

Slow relaxation and landscape-driven dynamics in viscous ripening foams

Proceedings of the National Academy of Sciences, Volume 122, Issue 47, November 2025. SignificanceFoams, like those in soap suds, shaving cream, or emulsions, can flow slowly and take a long time to recover after being squeezed or stirred. Scientists have long thought this sluggish behavior came from bubbles getting stuck in stable, jammed …