The question of whether a given trait qualifies as an adaptation must be answered on a case-by-case basis. Nevertheless, a strong case can be made for species as primarily adapted to their environments. A similar argument can be made for human cultures as primarily adapted to their environments at the group level. The reason that human cultures are primarily adaptive at the group level is because the capacity for culture is itself a group-level adaptation. Establishing a consensus on human cultures as primarily adapted at the group level will enable human cultural diversity to be studied in the same way as biological diversity.

Staphylococcus aureus (S. aureus) is a gram-positive bacterium that can cause severe infections such as pneumonia, osteomyelitis, and endocarditis when it breaches the skin. This study aimed to enhance the chemoenzymatic radiosynthesis of 2-deoxy-2-[18F]-fluoro-sakebiose ([18F]FSK), a radiotracer potentially useful for imaging S. aureus infections. By optimizing the synthesis of 2-deoxy-2-[19F]-fluoro-sakebiose ([19F]FSK), we identified key factors—such as increased enzyme concentration and decreased precursor levels—that significantly improved the yield. Applying these optimized conditions to the synthesis of [18F]FSK resulted in a 30% increase in the radiochemical yield (RCY%) from the control experiment. In vitro evaluation showed that [18F]FSK was successfully incorporated into two strains of S. aureus, suggesting its potential utility for imaging bacterial infections in vivo. This work lays the groundwork for using [18F]FSK in PET/CT imaging to diagnose and monitor S. aureus infections.