Global diversification of termite-Its pattern and causal mechanism

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The global diversification of termites was studied with reference to its pattern and causal mechanism as follows.(1) Adaptive radiation of Termes into soil-feeders : The evolution of feeding habits in Termes were studied by gut contents observation, stable isotope analysis, measurement of cellulase activities, and mitochondria DNA analysis in Australia, suggesting that the evolution into soil-feeding occurred once in Termes. The present study revealed the presence of amoeba with cellulase activity in Termes.(2) Evolutionary process from lower termites to higher termites : Termite fauna in the upland rainforest of Queensland of Australia, where Gondwana mesic forests have persisted since Cretaceous time, was compared with that in adjacent savanna formed in the Tertiary period. The former was dominated by lower termites, while the latter was dominated by higher termites. The higher termites seem to have evolved not in the forest but savanna.(3) Evolution of termite-symbiont system : Global diversification of termites was examined in relation to the evolution of termite-symbiont system and the sociality (T.Abe, S.A.Levin & M.Higashi eds, Biodiversity.Springer, 1997).(4) Ecological role of termites in ecosystem : The distribution of fungus-growing termites was examined together with their methane mission in the dry evergreen forest of Thailand.(5) Phylogeny of termites and biogeography : Phylogeny of Rhinotermitidae was examined in relation to their change in the symbiotic protozoa and their biogeography in the Japanese islands.(6) Workshop on the global diversification of termites : The workshop was held at Kyoto in March, 1997 to publish a textbook of the biology of termites. About 20 foreign termite researchers attended the meeting.