Drosophila buzzatii 56 Drosophila koepferae Cactaceae 38 Drosophila 38 Animals 32 article 30 animal 22 female 22 fly 20 Cactophilic Drosophila 18 Opuntia 18 Species Specificity 18 Male 16 male 16 nonhuman 16 species difference 16 Opuntia sulphurea 14 genetic variability 14 host plant 14 Diptera 12 Drosophilidae 12 Female 12 Hexapoda 12 Trichocereus terschekii 12 Wing 12 histology 12 Variation (Genetics) 10 body size 10 cactus 10 controlled study 10