Toshima Research Articles

Relationship between interspecific pollen transfer and pistil length in sympatric congeners, Clerodendrum trichotomum and C. izuinsulare

AbstractInterspecific pollen transfer (IPT) often leads to reproductive interference. Although character displacement of reproductive traits in plants is often considered a consequence of reproductive interference, few studies have tested whether intraspecific variation in floral morphology changes the intensity of reproductive interference among pollinator‐sharing plants. We investigated whether intraspecific variation in pistil length changes the proportion of IPT (interspecific pollen transfer) in sympatric populations of Clerodendrum trichotomum and C. izuinsulare on the two islands. On Toshima Island, C. izuinsulare flowers with shorter pistils were significantly less likely to receive C. trichotomum pollen, and there was a slight tendency for longer pistiles of C. trichotomum flowers to receive less C. izuinsulare pollen, suggesting that IPT has caused character displacement in pistil length in these congeneric plants. In contrast, we did not detect any relationship between pistil length and the proportion of IPT for the two species on Niijima Island. The discrepancy between the islands may reflect differences in pollinator assemblages.

Altitudinal zonation of forest vegetation and its causal factors in To-shima Island, Izu Islands, Japan

Altitudinal zonation of forest vegetation and its causal factors in To-shima Island, Izu Islands, Japan

Illegal Dumping of Solid Waste at Toshima Island and Countermeasures

Illegal Dumping of Solid Waste at Toshima Island and Countermeasures

伊豆諸島・利島 (としま) におけるつつが虫病の初報告例および第2例

It has been known that tsutsugamushi disease, so-called "Shichito-fever", is widely spread among the Izu Islands, Tokyo Metropolis. The cases were reported in Oshima Island, Niijima Island, Shikine Island, Kozu Island, Miyake Island, Mikura Island, and Hachijo Island previously, although no case has been reported in Toshima Island. In this paper, we report the first two cases of tsutsugamushi disease found in Toshima Island in December 1988 and December 1989. The first case was a 73 year-old male and the second case was a 83 year-old female, respectively. Fever, erythema and eschar were observed in both cases, while lymphadenopathy and hepatosplenomegaly were not detected. After tetracycline was administered, the fever immediately went down and erythema gradually disappeared in both cases. Specific immunofluorescence tests demonstrated that IgG antibody titers rose against Karp, Gilliam and Kato strains, and that IgM antibody titers rose only against Gilliam strain in both cases. Therefore, Gilliam-like strain of Rickettsia tsutsugamushi may play an important role in Toshima Island.

オオミズナギドリから得られた外部寄生虫３種について

In October 1981, I surveyed a colony of the Streaked Shearwater Calonectris leucomelas on Toshima Island in the Izu Islands, Japan, in order to collect ectoparasites. The following ectoparasites were collected from 6 Streaked Shearwaters (4 adults, 2 downy chicks): Mallophaga: (1) Longimenopon shiraii, (2) Halipeurus sawadai, and Shiphonaptera: (3) Ceratophyllus hagoromo. These bird lice were found on their hosts' (1) breast and abdomen on downy chicks; (2) axillars, dorsal, and wings of adults and downy chicks; and (3) on an adult and a downy chick in the same nest.

"Ihai" Cult in relation to Japanese Kinship and Family : Ancestor Worship in Toshima Island, Izu Archipelago

"Ihai" Cult in relation to Japanese Kinship and Family : Ancestor Worship in Toshima Island, Izu Archipelago

Some Physical Traits of To-shima Islanders

To-shima island is a small island (417km2) situated in the Pacific Ocean about 140km south-west of Tokyo. The population is composed of about 80 families and 360 peoples. This anthropological survey was carried out on the island in Summer 1957. The authors examined the anthropometrical measurements, the physical capacity (grip strength, tapping, match board test and reaction time), the finger and palmar prints, etc. of 83 adults and 156 school children. In this islanders, no peculier featuers are found in all of the traits examined, except in finger and palmar print patterns.

Studies on Marriage in Toshima Island of Izu, Tokyo.

2. A survey of marriage; Among 243 examples, 190 cases marriaged once, 10cases twice, and among the rest, only one side marriaged for the second time.The average age of the fist marriage was 24.0 in male, and 19.7 in female. The difference of age between husband and wife was, in average, 4.1. It was recognized that the age of fist marriage in male became older in Showa days.Among 84 married people in this village at present, 18.4 % married twice. besides, majority of remarriage occured because of the separation by death.

Studies on Marriage in Toshima Island of Izu, Tokyo.

4. A survey of birth and birth-control; The average numberof birth of a woman was 3.5, which is not so high. The number of birth tended to decrease in younger generation. According to the survey on birth-control, among 48 ansewers of whom used to practice birth-control, the economical reason proved 27.1 %. Besides, it was remarkable that artificial abortion was popular

Studies on Marriage in Toshima Island of Izu, Tokyo.

Studies on Marriage in Toshima Island of Izu, Tokyo.

Studies on Marriage in Toshima Island of Izu, Tokyo.

Studies on Marriage in Toshima Island of Izu, Tokyo.

Medical Studies on Rural Welfare at Toshima Island

Toshima Island, Tokyo, (one of Seven Islands of Izu) is a small island having 413 km2 in area and located at about 140 Kilometers south east of Tokyo City on the Pacific Ocean, and there is Mt. Miyatsuka (507.5 m in high) in the central part of the Island, natural features are very hilly. The auther investigated on Toshima village which is one of the villages of the Island and the result of the investigation on the outline of this village was as follows.According to my investigation on March 1956, the number of house-holds were 83 and the size of population wes 360. Increase and decrease of population were not noted by me. Average temperature of year round is 17.9... Due to not having river and water welling out, villager makes it a rule to stock rain water as their drinking water.Further, due to not having port in this island, the facilities of communication on the sea were always irregular, and also fishing was not easy and degree of cultural life was lower than the other district. As industry, the fruit and oil of camellia were main products and the quantities of these products occupied one third of that of Tokyo-To and it's farm land were occupied 22 per cent of all farm land in this island.

Medical Studies on Rural Welfare at Toshima Island

The Statistics of diseases at Toshima Island were obtained as follows :1. This survey was made by using medical record at a clinic established by Toshima village during the two following periods, from April 1953 to March 1954 and from March, 1956 to February 1957.(a) New cases at clinic were 470 during a period of a year from March 1956, 387 during from April, 1953 to March 1954, while the size of population on March, 1956 was 360 and that of on April, 1954 was 366.(b) About the classification of diseases, diseases of respiratory organs (mainly common cold), intestinal organs, nervous system, sensory organs and skin disease etc held greater part. Specific diseases which were characteristic to occupation were not recognized. The prevalence ratio of trachoma in school children decreased in recent year and was only 50 per cent in 1956.(c) The legal infectious diseases were not recognized at the time of the survey. The percentage of positive tuberculin reactor in younger age group was 60.7%.2. The intestinal parasites eggs were found in 36.0% of specimens examined. Ascaris in 30.2% and hookworm in 5.8%.3. The maximum blood pressure for over 31 years of age, in general, indicated lower tendency compared with that of the Japanese average. Maximum and minimum average figures were 131.0mmHg and 70.8mmHg in male, 132.6mmHg and 74.8mmHg in female.

Studies on the Farmer's Dwellings on Toshima (An Isolated Island of Seven Islands of Izu.)

The authors made an investigation and analysis of farmer's dwelling in Toshima Island, one of the i3olated island of the Seven Islands of Izu. The physical feature of the Island is characteristic because of steep cliff surounding the Island and a poor expansion of level area. Due to strong seasonal winds and rain, villages are located on the hilly part rich in groves of trees. According to the investigation performed, the following results were rea: hed :1. The area of the residential part is 598 sq. meter (180.8 tsubo) on the average and the floor space of the main dwelling average 80.3 sq. meter (24.3 tsub3) which means that houses are small in comparison to the size or the land.2. The length of time after the dwellings were built, is 40.9 years in average.3. The number of room found 4.1 per house and size of rooms per total space of house, 39.4 sq. meters (23.2 Joo) which is comparable to the s'ze of room of forming vil'age in other district but the number of inhabitants was found as 5.4 persons per house, which is less than in el: ewhere. Hence, the usable room space is 7.3 sq. meters (4.3 J o) per person which is larger than the national average of 6.1 sq. meter (3.6 J3o).4. The dwellung of the aged are detached.5. The scale of farming is small and means of production are limited and the size of attached buildings (earthen store rooms, store house and barns) is not large.6. The details of the dwellings, for example, kitchen, water supply, toilet and such things as location of barns, lighting and ventilation should resonably be improved

Medical Studies on Rural Welfare at Toshima Island

Medical Studies on Rural Welfare at Toshima Island