Dogs of War: The Effect of War-Inflicted Environmental Damage on Free-Ranging Domestic Dogs

Wars impose unprecedented environmental damage that has rarely been studied in real time. Domestic dogs are an accessible model species during war times, because they enable data collection without specialised equipment and skills, which can be performed without creating additional danger to humans or animals involved. We compared phenotypic traits in Ukrainian dogs living close to the front line with those from other regions of Ukraine. We found significant differences in frequencies and diversity of multiple morphological traits, consistent with mortality-based selection at the front line. We also found differences in age structure and frequency of diseases and injuries, consistent with high mortality of old and ill individuals. The front-line population had low average BMI and stable isotope analysis suggested malnutrition and low trophic level. Our study shows that wars can be factors of strong and fast natural selection, with the effects comparable to large-scale natural or anthropogenic disasters.