The wide range of observed social behaviours among domestic dogs can be attributed to several key factors:

 

Environmental pressures can trigger aggressive behaviours, especially in stressful environments like vets (Fig. 4), dog shows or parks, where tolerance and appeasement are common (Siniscalchi et al., 2018). People often walk reluctant dogs, thinking they need exercise, but forceful methods may cause negative reactions. Recognising that pets often communicate visually, it's vital for walkers to observe and interpret these signals correctly (Weber et al., 2026).

 

Resource Availability: Food, water, and shelter influence social organisation (Lazzaroni et al., 2025). In free-ranging settings, dogs compete for garbage, scraps, or handouts (Sen Majumder et al., 2016).

 

Abundant resources lead to group formation and tolerance (Sen Majumder et al., 2014), whereas scarce resources promote solitary or territorial behaviour (Biswas et al., 2023). In human settings, resource control can promote harmony, whereas inconsistency can spark competition over food, toys, and attention (Lazzaroni et al., 2025).

 

Social factors: Spaying and neutering reduce reproductive competition and can change social dynamics, including health (Lazzaroni et al., 2019). Age, sex, temperament, and communication also influence these dynamics (Siniscalchi et al., 2018). Puppies and juveniles are more socially tolerated, while adult males (Fig. 5) compete during breeding season due to promiscuity (Pal, 2003).

 

Human interventions: Training and socialisation help companion dogs navigate social worlds and build confidence when parameters are followed (Pryor, 2019). Whereas forcing a dog, mismanagement, or any inconsistency can cause behavioural issues (Almquist et al., 2026).