Evolutionary fine-tuning of background-matching camouflage among geographical populations in the sandy beach tiger beetle

カワラハンミョウの体色が生息地の砂色とよく一致することを解明 --場所ごとに異なる保護色の進化過程を明らかに--. 京都大学プレスリリース. 2020-12-17.Background-matching camouflage is a widespread adaptation in animals; however, few studies have thoroughly examined its evolutionary process and consequences. The tiger beetle Chaetodera laetescripta exhibits pronounced variation in elytral colour pattern among sandy habitats of different colour in the Japanese Archipelago. In this study, we performed digital image analysis with avian vision modelling to demonstrate that elytral luminance, which is attributed to proportions of elytral colour components, is fine-tuned to match local backgrounds. Field predation experiments with model beetles showed that better luminance matching resulted in a lower attack rate and corresponding lower mortality. Using restriction site-associated DNA (RAD) sequence data, we analysed the dispersal and evolution of colour pattern across geographical locations. We found that sand colour matching occurred irrespective of genetic and geographical distances between populations, suggesting that locally adapted colour patterns evolved after the colonization of these habitats. Given that beetle elytral colour patterns presumably have a quantitative genetic basis, our findings demonstrate that fine-tuning of background-matching camouflage to local habitat conditions can be attained through selection by visual predators, as predicted by the earliest proponent of natural selection

Direct observation of miniband-edge singularities in the optical spectra of GaAs/AlAs superlattices.

Band-edge optical transitions in GaAs/AlAs superlattices with different miniband widths are investigated by low-temperature-photocurrent, photoluminescence-excitation, and reflectance spectroscopy. Direct spectroscopic evidence is given for excitonic effects at saddle-type critical points which are related to ${\mathit{M}}_{1}$ Van Hove singularities at the upper miniband edges, for both heavy-hole and light-hole excitons. Excellent agreement is obtained between the observed transition energies and the miniband widths deduced from Kronig-Penney model calculations

Adjustment process of reasonable accommodation for students with disability

本研究の一部はJSPS科研費15K01683の助成を受けた。 本研究の一部は第45回中国四国大学保健管理研究集会（平成27年８月，徳島市），並びに第53回全国大学保健管理研究集会（平成27年９月，盛岡市）で発表した

Primary omental Gastrointestinal stromal tumor (GIST)

This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

東北メディカル・メガバンク事業 三世代コホート調査の進捗について

第3回日本DOHaD研究会学術集会　抄録集　【ポスター発表