A groundbreaking study recently published in PLOS One presents an unprecedented large-scale analysis of canine behavior and its variability over time, leveraging an extensive dataset collected from over 47,000 dogs enrolled in the Dog Aging Project between 2020 and 2023. This comprehensive research, spearheaded by Courtney Sexton, a postdoctoral associate at Virginia Tech’s College of Veterinary Medicine, alongside Yuhuan Li from the University of Washington, marks a significant milestone in the behavioral sciences and veterinary research by establishing an essential baseline from which the intricate relationship between dog behavior and health can be further explored.
Central to this investigation is the unique utilization of owner-reported behavioral data accumulated over four consecutive years. By drawing insights from such a vast and longitudinally consistent dataset, the researchers unlocked the ability to discern subtle trends, associations, and statistical significances that smaller datasets simply cannot capture. This volume and depth of data provide the analytical power required to scrutinize the dynamic changes in canine behaviors—including fear responses, excitability, aggression levels, and, notably, trainability—across different life stages and within the context of unprecedented global events such as the COVID-19 pandemic.
The temporal frame of the study coincides with a period of dramatic lifestyle changes worldwide, caused by pandemic-related social restrictions. This timing enabled the researchers to assess whether sudden environmental shifts and altered human routines tangibly affected the behavioral health of household dogs. Intriguingly, despite initial hypotheses suggesting considerable behavioral alterations in canine companions, the data indicates that dogs displayed a remarkable capacity for behavioral resilience and adaptability. Most behavioral metrics remained statistically steady throughout the years analyzed, underscoring the robust stability of canine temperaments even during extended periods of human societal upheaval.
However, one subtle yet statistically significant behavioral shift emerged concerning trainability. Dogs enrolled after the onset of the pandemic exhibited lower average trainability scores compared to those already enrolled as adults in 2020. While the data stops short of pinpointing exact causative mechanisms, the researchers postulate multiple interacting factors. Among these are the surge in shelter adoptions during the pandemic, which may have led to a higher proportion of dogs with limited formal training, and increased stress levels among owners limiting their availability or capacity to maintain consistent training regimens. The nuanced decline in trainability highlights how environmental and social stressors on the human side can indirectly ripple through and impact animal behavior.
From a methodological perspective, this study’s strength lies not only in its dataset size but also in its rigorous statistical framework, which accounted for variables such as sex, age, and size of the dogs. The multifactorial analyses incorporated complex models capable of managing hierarchical data structures and controlling for potential confounders. This approach ensured that the observed behavioral patterns were not artifacts of demographic differences but reflected genuine longitudinal trends. The findings confirm that life stage, sex, and body size are meaningful biological determinants that each modulate behavioral expressions in different but quantifiable ways.
The implications of this research extend beyond academic curiosity. By establishing a robust and validated behavioral baseline, this study lays the groundwork for future investigations into how aging, health status, and environmental factors influence canine behavior over time. The long-term vision is to integrate behavioral phenotypes with genetic, physiological, and health data to understand the multifaceted interplay shaping canine well-being. Such integrative insights hold promise for advancing veterinary medicine, improving animal welfare, and augmenting the human-animal bond under diverse living conditions.
Moreover, the study highlights the feasibility and scientific utility of large-scale owner-reported data collection within a “citizen science” framework. By engaging thousands of dog owners nationwide, the Dog Aging Project demonstrates a scalable model for longitudinal animal behavior studies that is both cost-effective and ecologically valid. Owner-reported outcomes, when gathered systematically and at scale, can yield high-resolution behavioral datasets that complement traditional observational and experimental methodologies.
Despite the successes, the researchers acknowledge the inherent limitations of their approach. Owner-reported data, while rich and expansive, can be subject to bias, including variability in owners’ interpretations of behavior and inconsistencies in reporting diligence. Future analyses may benefit from triangulating these data with objective behavioral assays and physiological biomarkers to strengthen causal inferences. Furthermore, exploring geographic variability and cultural factors may uncover additional layers of complexity in the behavioral ecology of companion dogs.
Looking ahead, the team envisions expanded analyses incorporating health status variables to investigate how disease processes and aging trajectories influence or are influenced by behavioral changes. They also anticipate leveraging machine learning algorithms to detect subtle behavioral phenotypes and predictive markers that could inform individualized care and intervention strategies. Ultimately, such advancements could facilitate tailored behavioral counseling and therapeutic regimens that proactively support dogs and their owners through different life phases and challenging circumstances.
The timing of this publication is particularly poignant as communities worldwide continue to navigate the lingering effects of the pandemic and its aftershocks on mental and physical health. This research subtly underscores dogs’ resilience and adaptability, reflecting a broader biological principle of homeostasis under environmental stress that resonates across species. It also reinforces the vital role that companion animals play in human society, offering emotional support and companionship in times of uncertainty, even as their own behaviors are influenced by the shared environments.
By presenting an expansive behavioral dataset tied to demographic and temporal variables, this Virginia Tech-led study provides a foundational resource for veterinarians, animal behaviorists, and researchers aiming to decode the complexities of canine behavior across the lifespan. This pioneering effort fuels optimism that a deeper, empirically grounded understanding of the canine mind and body will emerge in the coming years, enhancing the science of companion animal care and welfare in unprecedented ways.
Subject of Research: Canine behavioral characteristics and variability over time based on owner-reported data from 47,444 dogs in the Dog Aging Project.
Article Title: An analysis of behavioral characteristics and enrollment year variability in 47,444 dogs entering the Dog Aging Project from 2020 to 2023.
News Publication Date: 10-Sep-2025.
Web References: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0330257
Image Credits: Photo courtesy of Courtney Sexton.
Keywords: Dogs, Organismal biology, Animal science, Veterinary medicine, Animal health, Veterinary parasitology, COVID 19, Health and medicine.
