Global patterns, biases, and advances in phylogeographic and genetic structure studies in Drosophilidae (Insecta: Diptera).

Phylogeographic and genetic structure studies involving Drosophilids have clarified numerous processes that have shaped the evolution of biodiversity over time. In this review, we aim to (i) assess the main biases, gaps, and advances in the scientific literature on this topic; (ii) synthesize the major findings emerging from these studies; and (iii) identify congruencies and discrepancies in the phylogeographical histories of different species and regions. To achieve these goals, we conducted a comprehensive review of peer-reviewed literature on phylogeographic and genetic structure studies of Drosophilidae published between 1987 and 2024. After identifying and filtering relevant studies, we extracted and analyzed key information related to each topic. Overall, we have detected a straightforward predominance of studies involving species of the Drosophila genus, especially within the melanogaster, obscura, and repleta groups. Interestingly, most studies employed nuclear DNA markers, either alone or in combination with mitochondrial markers, and were conducted across more than one biogeographical region, primarily in the Palearctic and Nearctic. Thus, our synthesis underscores the importance of broader taxonomic sampling and increased attention to understudied regions to enhance our understanding of biodiversity dynamics in response to environmental changes at both local and global scales.