The article discusses how social interactions have influenced the evolution of cognitive abilities in animals. It suggests that animals have different levels of social cognition skills, from basic recognition of others to understanding their relationships and possibly their thoughts. These skills have evolved based on the need for animals to navigate social environments effectively. The researchers propose that more complex social cognition indicates stronger evolutionary pressures in the past. They also suggest that individual differences in social cognition may be linked to differences in reproductive success. The presence of these skills can be observed and tested in the field, allowing for comparisons across species and within species.