At what stage of speciation do differences emerge in genitalia: an approach using micro moths

2022 Fiscal Year Final Research Report

• Project/Area Number: 20H03312
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 45030:Biodiversity and systematics-related
• Research Institution: Kyoto Prefectural University
• Principal Investigator: Ohshima Issei 京都府立大学, 生命環境科学研究科, 准教授 (50466455)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 種分化 / 昆虫 / 種分類

Outline of Final Research Achievements

The unit "species" that we usually use is almost always defined based on morphological differences. In contrast, studies of speciation have focused on the presence or absence of isolating mechanisms and the degree of gene flow. Therefore, there is a mixture of species criteria with large gaps in both the definition and the actual degree of diversification. Therefore, in this study, we used mating ability and genomic differentiation as indices, and investigate at what stage of speciation do differences emerge in genitalia. As a result, it was suggested that adaptation to host plants occurred in the early stage of speciation, followed by differentiation of mating ability. However, differentiation in genital morphology was suggested to occur the latest stage of speciation.

Free Research Field

進化生物学

Academic Significance and Societal Importance of the Research Achievements

「種」という概念は，我々が日常で生物に関する情報をやりとりをする上でも不可欠なものである．ただし，多くの種は形態的な違いに基づいて定義されてきたが，この「形態差」がみられるという段階がどの程度生物どうしとして分化した状態であるのかは，ほとんど調べられてこなかった．そのため，ごく些細な形態差で区別された種などは，その形態差が本当に種の分化を示しているのかという疑問は，生物の愛好者を含め多くの人が抱く疑問であった．本研究により，昆虫においては，微細であっても質的な形態差は種分化のかなり後半で生じることが示唆され，このような形態差が見られる分類群間には他の生殖隔離も生じていると考えられる．