Origin and phylogeny of Scaptomyza (Diptera: Drosophilidae)

2014 Fiscal Year Final Research Report

• Project/Area Number: 24570092
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Biodiversity/Systematics
• Research Institution: Hokkaido University
• Principal Investigator: KATOH Toru 北海道大学, 理学(系)研究科(研究院), 助教 (80374198)
• Co-Investigator(Kenkyū-buntansha): DICK Matthew. H. 北海道大学, 大学院理学研究院, 非常勤講師 (80374205)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 分子系統 / ショウジョウバエ / 分岐年代 / 祖先分布

Outline of Final Research Achievements

The genus Scaptomyza is one of the incredibly diversified groups in the family Drosophilidae, in which about 60% species are endemic to Hawaiian Islands while the remaining species are distributed in continents. There have been two alternative hypotheses for the origin of Scaptomyza. One is that the genus originated in Hawaii and subsequently diversified in continents, another is that these species originated in continents and subsequently colonized in Hawaii. In order to verify this problem, we determined the nucleotide sequences of 11 genes for the 11 species of Scaptomyza. Together with the homologous sequences for 79 species, we reconstructed the phylogenetic trees and then inferred the ancestral distributions and divergence times. Our results revealed that Scaptomyza would have originated outside Hawaii, supporting the continental origin hypothesis. In addition, our results revealed that the migration of Scaptomyza from continents to Hawaii would have occurred twice independently.

Free Research Field

分子系統学