How did Carolus Linnaeus mix descriptions of culture with physical traits?

Carolus Linnaeus conflated physical traits with cultural characteristics in his 18th-century classifications of the human species, a practice that reflected the ethnocentrism and limited scientific understanding of his time.12

When categorizing humans into four major subdivisions—H. americanus, H. africanus, H. europaeus, and H. asiaticus—Linnaeus included descriptions of temperament and customs alongside biophysical features. These cultural observations, such as descriptions of behavior and social habits, were treated as inherent traits of these groups, despite having no basis in biological reality. By integrating these learned behaviors into his taxonomic system, Linnaeus gave human groups a sense of rigidity and permanence, effectively rendering cultural differences as part of the natural order.12

It is important to recognize that this approach was scientifically flawed, as it failed to distinguish between biological characteristics and culture. Furthermore, some of his categories, such as H. monstrosus and H. ferus ("wild man"), were based on myths and travelers' tales rather than empirical observation, highlighting the subjective and non-scientific nature of these early racial classifications.12