22/01/2026
We all know that dogs have, over many decades and even centuries, adapted to a life alongside humans. However, their ability to co-exist with people have exposed them to the risk of many diverse traumatic experiences. Selective breeding has an impact on how severe the fallout of these experiences can be as some breeds were created to be more resilient to stress, overly social, aggressive to humans or other dogs, etc.
Considering where most people get their puppies from it goes without saying that puppies acquired from advertisements on social media and other sources could very likely have had adverse experiences even before they end up in their new homes. For an 8 week old puppy, just separated from his mother and siblings, to be flown in a cargo hold of an aeroplane over long distances is extremely traumatic.
In a study that came out in 2025 Influence of early life adversity and breed on aggression and fear in dogs by Espinosa, J., Zapata, I., Alvarez, C.E. et al. . Sci Rep 15, 32590 (2025) the interaction between heritable and acquired traits is looked at in more depth.
From a broader perspective the study points to a substantial overlap related to adverse early life experiences that can influence the psychological wellbeing of dogs, humans and other species.
The study found that both breed specifics and early experiences can impact the level of aggressive behaviour in adult dogs. If a dog had any unpleasant experiences during the first six months of his life such as abuse or abandonment the dog will very likely display increased aggression and fearfulness as an adult. Additionally some breeds were more susceptible to the impact from harsh conditions than others, particularly breeds that were historically bred for livestock guarding or bringing down game.
One environmental factor that can increase fearful and aggressive behaviour is when dogs live with children. This is an important consideration as children are common targets of aggression. The risk of aggression is high because children are mostly unable to interpret a dog’s behaviour correctly during inappropriate or unsupervised interactions.
The study goes into great detail and lists different breeds to support these findings. If you are interested in the details please go to
Among the animals on this planet, dogs are uniquely adapted for life with humans, a status that exposes them to risks of human-mediated traumatic experiences. At the same time, some lineages of dogs have undergone artificial selection for behavioral phenotypes that might increase risk or resilience....
