cross breeding Crosses, Genetic 30 genetics 30 article 28 Animals 20 Male 20 animal 20 male 20 female 18 Female 14 genetic variability 14 histology 14 Argentina 10 Drosophila 10 nonhuman 10 phenotype 10 Chromosomes 8 Genotype 8 Phenotype 8 controlled study 8 evolution 8 genotype 8 hybrid 8 physiology 8 sexual development 8 Adaptation, Physiological 6 DNA sequence 6 Drosophila buzzatii 6 Drosophila melanogaster 6 Flowers 6