Ecological and Physiological Basis underlying Acquisition of Behavioral Laterlity

2014 Fiscal Year Final Research Report

• Project/Area Number: 24405001
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 海外学術
• Research Field: Neuroscience in general
• Research Institution: Nagoya University
• Principal Investigator: ODA Yoichi 名古屋大学, 理学(系)研究科(研究院), 教授 (00144444)
• Co-Investigator(Kenkyū-buntansha): HORI Michio 京都大学, 大学院理学研究科, 名誉教授 (40112552) ; TAKEUCHI Yuichi 富山大学, 大学院医学薬学研究部(医学), 助教 (40508884)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: タンガニイカ湖 / 鱗食シクリッド / 左右性 / 口部形態 / 発達 / 利き / 種内二型 / マウスナー細胞

Outline of Final Research Achievements

The skewed-mouthed scale-eating cichlid Perissodus microlepis in Lake Tanganyika is an attractive model of behavioural laterality: each adult robs scales from its prey fishes’ left or right flanks according to the direction in which its mouth is skewed. To investigate the development of behavioural laterality and mouth asymmetry, we analysed stomach contents and lower jaw-bone asymmetry of various-sized P. microlepis sampled in the southern tip of the Lake. The shapes of the pored scales found in each specimen’s stomach indicated its attack side preference. Early-juveniles (SL <45mm) feeding on zooplankton exhibited slight mouth asymmetry. After scale-eating began, the attack side preference was gradually strengthened, as did mouth asymmetry. Our findings show that mouth asymmetry in P. microlepis precedes behavioural laterality, which is established in association with mouth development, and suggest that physical and behavioural lateralities confer a synergistic advantage.

Free Research Field

神経科学