日 時 : 8月24日(水) 15:00~17:30
    場 所 : 5F 547室

テ ー マ 講 演 者 連 絡 先
Mapping potential dragonfly habitats using environmental surrogate measures(日本語で発表の予定)椿 宜高
(国立環境研究所 生物多様性プロジェクト)
山 中
内   容
   The success of biological conservation is measured in terms of the amount, quality and health of the biological diversity maintained (Samways 2005). Therefore, we need sound taxonomy and good distributional data, which are often not available for insects. Conservation area selection then depends on using coarse, but not inaccurate, data that are available on relatively well known species (or species assemblages) such as birds, butterflies and dragonflies. Therefore surrogate data are often used for making informed conservation decisions. Environmental surrogate measures include vegetation types, land systems or classes, climate and environmental domains. These environmental surrogate measures are often available from national geographic information facilities.
   Some countries, including Japan and Britain, have national recording schemes. Records reported by the network of volunteer recorders provided, to some extent, comprehensive coverage of the country. These are immensely valuable for determining how well or not species are doing over time, as well as the extent of the geographical ranges of species. The outcome has been the production of an atlas (Japan Integrated Biodiversity Information System), which provides an immediate visual overview of present geographical ranges.
However, there are shortcomings with these 'record point maps'. Firstly, the records are accumulated in an ad hoc manner, resulting in geographically biased records (for example, due to uneven spatial distribution of recorders). Secondly the data only record what is present and not what is absent. Thirdly, records are taxonomically biased because recorders may be keen to record rare species rather than common ones.
   Fourthly, abundance is neglected though it gives important survival implications for populations.
   I have developed a method for data quality validation, to overcome some of these shortcomings inherent to the national recording schemes. I have selected only high quality data from the original data set, for the use in the analysis of relational spatial database. As the results, I could detect a continuous array from an extreme generalist to a specialist in odonate fauna, which reflects species・ forest independency or dependency.
テ ー マ 講 演 者 連 絡 先
Male avoidance of sperm competition and female avoidance of multiple mating in a damselfly Mnais costalis(日本語で発表の予定)椿 宜高
(国立環境研究所 生物多様性プロジェクト)
山 中
内   容
   Since Waage's discovery on Calopteryx maculata (1979), in which male of uses its penis not only to transfer sperm to the female but also to remove sperm deposited in the female's sperm storage organs from previous copulations, dragonflies have become a popular animal groups in the field of behavioral strategies of both sexes in the context of sperm competition and sexual selection.
   I will briefly summarize our study on a damselfly Mnais costalis, together with the previous study on the related species M. pruinosa, highlighting basic sperm competition features of this species (or genus). Mnais costalis shows a genetic polymorphism in male wing-color, which linked to territorial and non-territorial reproductive strategies: orange-winged males are territorial, while clear-winged males are non-territorial sneakers. Orange winged males usually showed short copulation duration , while clear winged males showed bimodal copulation duration . Copulation duration was not morph specific but correlated with the male-female encounter site: copulation duration was shorter at oviposition sites, while it was longer at feeding sites. Copulation duration reflected the amount of sperm the male removed from female sperm storages. P2 value immediately after copulation was almost 100% because of position effects, even if the last male did not remove all rival sperm, but it decreased within a few days due to sperm mixing. Therefore, the copulation duration represents a male's flexible strategy to avoid sperm competition (by modifying the effects of sperm removal and sperm positioning) under a condition of slow sperm mixing rate.
   Perching nearby the female (non-contact guarding), territorial males guard his ovipositing female from harassment by conspecific males. While a male is guarding an ovipositing female (his former mate), he often finds himself guarding other conspecific females who arrived after he began to guard and who are ovipositing in company with his mate. Late arriving females are, in effects, stealing a guard (SAG). The benefit of SAG to the females has been suggested to be considerable: the opportunity to oviposit in a high-quality site, protected from harassment and without paying the usual cost of an additional copulation with the territory holder. In addition, I would suggest that SAG trial might indirectly function to discriminate variations in male quality. This was supported by the evidence that a smaller proportion of females were successful in SAG trial at territories occupied by quality males.
テ ー マ 講 演 者 連 絡 先
アゲハ幼虫の擬態紋様形成を制御する分子機構二橋 亮
山 中
内   容
  昆虫は、外敵から身を守ったり、獲物を捕えたりするために、さまざまな方法で自らを他に似せる「擬態」を行なっている。擬態に関する研究は生態学・行動 学的な面から進められてきたが、擬態を作り出す分子メカニズムついては、これまで ほとんど明らかにされていない。今回、アゲハ幼虫の擬態紋様形成について紹介する。
 次に黒色部の領域変化に着目し、黒色色素であるメラニンの合成に関わる複数の遺伝子をアゲハでクローニングして、その発現をwhole -mount in situ hybridizationで比較した。その結果、Tyrosine hydroxylase (TH), Dopa decarboxylase (DDC)の2の酵素が、ステージごとに将来黒くなる領域で強く発現することが確認された。培養皮膚を用いた実験からも、これらの酵素が領域特異的に発現することにより、将来の黒色紋様が制御されていることが示された。また、メラニン合成に関与するebony遺伝子 はアゲハの幼虫では目玉模様の赤色部の形成に必要であることも示唆された。さら に、THの補因子を産生するGTP cyclohydrolase I (GTP-CHI)は、アゲハ幼虫皮膚では 2つのisoformが発現しており、一方が紋様特異的であることも確認された。
 以上の結果から、アゲハの幼虫はステージに応じて紋様形成に関わる遺伝子の発現量 や発現領域を変化させていることが明らかになったが、ホルモン投与実験から、幼虫 の紋様のパターン決定には幼若ホルモンが、色素合成にはエクジソンがそれぞれ重要 な役割を果たしていることも見出したので、ホルモンとパターン形成や色素合成との 関連も含めて紹介したい。

    日 時 : 8月26日(金) 15:30~17:00
    場 所 : 5F 547・549室

テ ー マ 講 演 者 連 絡 先
Simulating impact of climate change on rice yield and adaptation strategies for rainfed agro-ecosystem Dillip Kumar Swain, Ph. D.
(Environment and Sustainable Development,United Nations Univ.)
吉 本

    日 時 : 8月30日(火) 16:00~17:00
    場 所 : 5F 中会議室(547号室)

Development of method of ecological risk assessment of pesticides on caddis fly
テ ー マ 講 演 者 連 絡 先
How to select aquatic insects for ecological risk assessment of pesticide.Inter- and intra-specific variation of sensitivity of caddis flies larvae to fenitrothion ?
横山 淳史 大津
テ ー マ 講 演 者
The status quo and problems of indoor breeding system and acute toxicity test for hazard assessment of pesticide on caddis fly (Cheumatopsyche brevilineata) larvae.
大津 和久

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