The relationships within Drosophila melanogaster species group are controversial from morphology, chromosomes and DNA sequences. This study utilises a molecular approach aimed at uncovering the phylogenetic relationsh...The relationships within Drosophila melanogaster species group are controversial from morphology, chromosomes and DNA sequences. This study utilises a molecular approach aimed at uncovering the phylogenetic relationships among 33 taxa representing 8 subgroups of D. melanogaster species groups. Mitocondrial ND4L-ND4 was sequenced in the all 8 subgroups covering a wide geographic area. MP and Bayesian analysis produced an identical tree topology with relatively strong support in most nodes. It reveals that the melanogaster species group clustered in three main lineages：1）montium subgroup; 2） ananassae subgroup; 3） Oriental subgroups （ melanogaster, ficsphila, eugracilis, elegans, syzukii and takahashii）. The montium subgroup branched off first, followed by the ananassae subgroup. In the third lineage, melanogaster is the most divergent subgroup followed by ficsphila, eugracilis, elegans in that order. The suzukii and takahashii sister subgroups are the last to branch off.展开更多
Acipenseriformes is an endangered primitive fish group, which occupies a special place in the history of ideas concerning fish evolution, even in vertebrate evolution. However, the classification and evolution of the ...Acipenseriformes is an endangered primitive fish group, which occupies a special place in the history of ideas concerning fish evolution, even in vertebrate evolution. However, the classification and evolution of the fishes have been debated. The mitochondrial DMA (mtDNA) ND4L and partial A7D4 genes were first sequenced in twelve species of the order Acipenseriformes, including endemic Chinese species. The following points were drawn from DNA sequences analysis: (i) the two species of Huso can be ascribed to Acipenser; (ii) A. dabryanus is the mostly closely related to A. sinensis, and most likely the landlocked form of A. sinensis; (iii) genus Acipenser in trans-Pacific region might have a common origin; (iv) mtDNA ND4L and ND4 genes are the ideal genetic markers for phylogenetic analysis of the order Acipenseriformes.展开更多
文摘The relationships within Drosophila melanogaster species group are controversial from morphology, chromosomes and DNA sequences. This study utilises a molecular approach aimed at uncovering the phylogenetic relationships among 33 taxa representing 8 subgroups of D. melanogaster species groups. Mitocondrial ND4L-ND4 was sequenced in the all 8 subgroups covering a wide geographic area. MP and Bayesian analysis produced an identical tree topology with relatively strong support in most nodes. It reveals that the melanogaster species group clustered in three main lineages：1）montium subgroup; 2） ananassae subgroup; 3） Oriental subgroups （ melanogaster, ficsphila, eugracilis, elegans, syzukii and takahashii）. The montium subgroup branched off first, followed by the ananassae subgroup. In the third lineage, melanogaster is the most divergent subgroup followed by ficsphila, eugracilis, elegans in that order. The suzukii and takahashii sister subgroups are the last to branch off.
文摘Acipenseriformes is an endangered primitive fish group, which occupies a special place in the history of ideas concerning fish evolution, even in vertebrate evolution. However, the classification and evolution of the fishes have been debated. The mitochondrial DMA (mtDNA) ND4L and partial A7D4 genes were first sequenced in twelve species of the order Acipenseriformes, including endemic Chinese species. The following points were drawn from DNA sequences analysis: (i) the two species of Huso can be ascribed to Acipenser; (ii) A. dabryanus is the mostly closely related to A. sinensis, and most likely the landlocked form of A. sinensis; (iii) genus Acipenser in trans-Pacific region might have a common origin; (iv) mtDNA ND4L and ND4 genes are the ideal genetic markers for phylogenetic analysis of the order Acipenseriformes.
