Two decades of colonization of the urban environment of Porto Alegre, southern Brazil, by Drosophila paulistorum (Diptera, Drosophilidae)

Drosophila paulistorum Dobzhansky & Pavan, 1949 had initially been considered absent in anthropogenically disturbed environments, but in 1985 the detection of the species in Porto Alegre city, southern Brazil, suggested its potential to colonize new habitats and laid the foundations for ecologic studies on this species' populations. This study followed the variations in D. paulistorum populations in this town almost 20 years after its first local record. Drosophilid specimens were collected in sites with different urbanization grades and the results point to the expressive decline in D. paulistorum populations in Porto Alegre. This decline may be linked to urban growth and to naturally driven population decline, as imputed to climatic changes like variations in maximum and minimum temperatures as a consequence of a global climate warming. Also, the recent introduction of exotic species Zaprionus indianus Gupta, 1970 seems to play a role in this scenario, changing the interactions between native species.

Calliphorid fly (Diptera, Calliphoridae) attraction to different colored traps in the Tingua Biological Reserve, Rio de Janeiro, Brazil

The present study intended to analyze calliphorid attraction to traps painted in a variety of colors and the calliphorid constancy index in the Tingua Biological Reserve, Rio de Janeiro state, Brazil. The Diptera were collected monthly in the Reserve, between 2002 and 2005, totaling 24 samplings. Four traps containing sardines as bait were painted olive green, blood red, black, or white and exposed for 48 h at four equidistant points, 50 m from each other. To determine the calliphorid species constancy, the Bodenheirmer constancy index was used throughout the study. To analyze differences in the total abundance between species and in their color selection, an ANCOVA test with a significance level of 5 % and a Tukey post-test were used, considering the categories species and color as cofactors and climatic variables as co-variables (temperature, relative humidity and precipitation), since the samples were collected over two years. 10,444 insects were captured. Of these, 56 % belonged to the Calliphoridae family, totaling 13 species, with the most frequent species being Laneela nigripes (28.5 %), Hemilucilia semidiaphana (17 %), and Mesembrinella sp. (16.4 %). The other species had frequencies lower than 12 %. Nine species were considered constant, two accessories, and two accidental. The data indicated that the most frequent species presented significant differences between themselves concerning abundance over the captured months, however, the Tukey post-test indicated differences only between a few of them. The black trap presented the higher relative calliphorid frequency (27.34 %), followed by green (25 %), red (24.0 %), and white (23.7 %), although the species abundance in the different colored traps did not differ significantly among themselves. Therefore, there was no Calliphorid flies preference for any of the tested colors.

Can climate shape flight activity patterns of Plebeia remota Hymenoptera, Apidae)?

Flight activity of foragers of four colonies of Plebeia remota (Holmberg, 1903) was registered from December 1998 to December 1999, using an automated system (photocells and PLC system). The colonies originated from two different regions: Cunha, state of São Paulo, and Prudentópolis, state of Paraná, Brazil. Flight activity was influenced by different climatic factors in each season. In the summer, the intensity of the correlations between flight activity and climatic factors was smaller than in the other seasons. During the autumn and winter, solar radiation was the factor that most influenced flight activity, while in the spring, this activity was influenced mainly by temperature. Except in the summer, the various climatic factors similarly influenced flight activity of all of the colonies. Flight activity was not affected by geographic origin of the colonies. Information concerning seasonal differences in flight activity of P. remota will be useful for prediction of geographic distribution scenarios under climatic changes.

Estudos sobre condução nuclear: I - aspectos qualitativos observados em systemas impolarizaveis

As experiencias demonstram que a conducção nuclear tambem se processa nos systemas praticamente impolizaveis, (metal/sol. do mesmo metal), onde é bem determinada e caracteristica. O estudo destes systemas pode fornecer dados seguros para a analyse do phenomeno da polarização, assim como do electrotonus physico do nervo. Na proxima nota analizaremos o phenomeno quantitativamente e esboçaremos sua theoria. Desejamos deixar expresso os nossos agradecimentos aos Professores Miguel Osorio de Almeida e José Felippe, pela attenção com que acompanham nossos trabalhos, assim como pelas suggestões que nos foram feitas, e ao Professor Evandro Chagas o nos ter facilitado o uso do Electrocardiographo.

Influência de elementos climáticos na mortalidade de cidades brasileiras

In this paper, preliminary to a series of investigations that the A. has the purpose to make about the influence of climatic factors particularly upon the prevalence of the most important acute infectious diseases in Brazil, he raises the question whether such factors do affect in this country the total death rates, as it is reasonable to suppose, according to what has been observed in temperate zones of northern and southern hemispheres. The inclusion of absolute humidity among other climatic factors to be dealt with seems justifiable according to Rogers and Stallybrass. Owing to scarcety of reliable data the A. was obliged to limit to a five-years period (1940-1944) the complete proposed investigation, which includes seven of the most important cities, scattered throughout the brazilian territory, from north to south - Belém, recife, Salvador, Rio, S. Paulo, Curitiba and Porto Alegre. Reference is made to their normal climatic conditions and monthly death-rates variations with their mean values and standard deviations. In a first part dealing with seasonal variations only for purposes of comparison, he points out that in there tropical cities of Brazil, without very clear seasonal differentiation, the curve of general mortality reached its highest point in austral autumn season and the remaining four (including Rio near the tropic) in the spring, with the exception of Curitiba, where the peak coincided with the summer season. He shows how such important causes of deaths, as diarrheas, common respiratory diseases and tuberculosis, whose seasonal distribution for each one of the seven cities is referred, may explain such seasonal variations. On a second part, a study is made of the general mortality distribution by four-months periods selected in accordance respectively with the highest or lowest values of rainfall and of mean temperature and humidity during period 1940-1944. Finally he compares the monthly waves of such climatic factors and the corresponding waves of total death - rates and finds through correlation coefficients 17 significant values with respect to their standard errors. Variations in the death - rates seemed to be perhaps more closely and uniformly associated with variations of mean humidity, as is indicated by coefficients ranging from + 0.3 to 0.6.

Doenças intestinais em cidades brasileiras: associação com elementos climáticos

Enteric fevers and dysenteries showed, during the period 1940-44, a summer prevalence in brazilian cities of the temperate zone. The distribu¬tion of the diseases by four-months periods, selected in acordance with the highest of lowest values of rainfall, mean temperature and absolute humidity induced to suppose that, in those cities, and also in tropical ones, both enteric fevers and dysenteries were closely associated with such climatic factors: enteric fevers mainly with absolute humidity and temperature, and dysenteries with humidity and rainfall. Correlation coefficients, statistically significant, have been obtained comparing monthly waves of climatic factors and corresponding waves of prevalence of the diseases. For enteric fevers, clear associations have been disclosed: with temperature variations in all temperate cities (coefficients ranging from + 0.42 to + 0.75, higher with mean temperature in the previous month) and in two of the four tropical cities (from + 0.26 to ± 0.30); with absolute humidity variations in cities of the first group (from + 0.51 to 0.71) and in the tropical city of Rio ( + 0.26 ± 0.12 and + 0.28 ± 0.12); and also with rainfall variations but only in two temperate cities (from + 0.28 to + 0.64). For dysenteric diseases, in cities of temperate zone similar associations have been found with absolute humidity (values of r, ranging from + 0.32 to + 0.45), with temperature (from + 0.26 to + 0.44); and with rainfall only in Curitiba ( + 0.25 ± 0.12). Recife (tropical city) yielded two significant values : r = — 0.27 ± 0.12 (correlation with mean temperature in the same month) and r = + 0.40 ± 0.11 and -h 0.37 ± 0.11 (between monthly morbidity rates and rainfall, respectively in the same month and in the previous one). Deaths by diarrhea and enteritis, in the cities of the temperate zone, prevailed in spring-summer seasons, also in four-months periods of highest temperature and humidity, for those cities and for the tropical ones, with the exception of Belem in which percentages were identical to those of opposite periods. Still with the exception of Belem, in all cities studied positive correla¬tion coefficients, statistically significant, have been obtained with temperature variations (ranging from + 0.25 to + 0.65 in tropical cities, and from + 0.47 to + 0.76 in temperate zone) and with humidity variations (from + 0.34 to + 0.44 in the first group, and from + 0.43 and + 0.74 in the second) . With rainfall, only Rio (in the tropical region) showed a significant value for r ( + 0.26 ±0:12); similarly in S. Paulo and Curitiba, the values ranged from + 0.46 to + 0.56, while in Porto Alegre there were found — 0.26 ± 0.12 and — 0.32 ± 012, for rainfall variations in the same and previous months.

Estudos dos agrupamentos vegetativos relacionados com as áreas onde foram efetuadas as pesquisas sôbre a febre amarela silvestre no Município de Passos, Estado de Minas Gerais

The work reported here was carried-out on the invitation of Dr. Henry Kumm, Director of the Rockefeller Foundation, and by appointment from Dr. Henrique Aragão, Director of the Instituto Oswaldo Cruz. It was done during the investigation of sylvan yellow fever, in June 1947, with a view to establishing the phyto-ecological conditions of the county of Passos. The pe¬riod was, however, too short for definite conclusions to be reached. Thanks are due to Dr. O. R. Causey, Chief of Research on Yellow Fever for transpor¬tation and other help. THE REGIONAL VEGETATION. Aerial photographs of the county of Passos shoto that it is covered by three great types of vegetation: Rain Forest, Secondary Pasture Land and Scrub.1 Detailed investigation, however, brings out the fact that these correspond to different seres; furthermore, each type presents not only the specific, characteristics of the biological form dominant for the climate, but also are at various stages, which express HABITATS differing from those of the normal sere. The phytogeographic survey of the region shows that most of it is now covered by secondary pasture land (disclimax) in which Melinis minutiflora, v. "fat grass" (fig. 1), predominates. The mosaic of Rain Forest and of small patches of Scrub reveals the effects of human intervention (BARRETO, H. L. de Mello 1); consequently, all the formations have to be regarded as secon¬dary, though some of them probably include relicts of the primitive climax (WARMING, E. 2). On close examination, the Scrub cannot be considered as the climax, because of the following facts: 1. In the zone of Rain-Forest stretches of forest are present in very varied topographic conditions and the reconstitution of the associations show that man has destroyed an ecological unit (fig. 2). 2. In the zone of Scrub the characteristic patches are small. The banks of rivers and brooks, the valleys and ravine and whatever the soil has retained some humidity, is being invaded fry Rain Forest, which seems to be growing under optimum conditions. The Scrub is thus limited to small belts on the calcareous mountains and on sandy soils with alcaline depths (pH abo¬ve 7) which do not retain enough moisture for the Rain Forest that is progres¬sively restricting the area occupied by Scrub. In view of the topographic and present climatic conditions the Rain Forest must consequently be regarded as the regional climax. The presence of ecologically contradictory elements and associations shows that the real problem is that of the fluctuations of the climate of Passos or even of Minas Geraes during the quaternary and recent periods (DAN-SEREAU, P. : 3), a subject on which little is known and which is tied to the evolution of the climate of Brazil (OLIVEIRA, E. : 4) . The transformation of Scrub into Rain Forest has been - observed by the author before, in other parts of Brazil (VELOSO, PL P.: 5) . It seems probable that the Rio Grande has also greatly influenced the change of the regional vegetation, by invading areas of Scrub and dislocating the limit of the Pluvial climate towards the Canastra Range, though there are remnants of Scrub (postclimax) transfor¬med into secondary open country (disclimax, fig. 5) by human devastation and the setting of fire to the land. VEGETATION GROUPS OF THE PLUVIAL TYPE. The map of the region also shows that at the present time the small patches of forest (whether devasted or intact) occupy the least accessible places, such as valleys, peaks and abrupt slopes (fig. 2). Even these are now being destroyed, so that in the near future this forested region will be en¬tirely reduced to poor pasture land unless energetic measures of conservation are undertaken in time. The Special Service for Prophylaxis against Yellow Fever installed two of their four Stations for the Capture of Mosquitos in this area, one of them at Batatal and the other at Cachoeira, which have separate formations each of them composed of several associations. Other vegetation formations were also analysed, from the synecological point of view, so as to ascertain of which degree of succession their associations belong. These phytosociological sur¬veys give an idea of the principal characteristics of each station. BATATAL FORMATION. The abrupt nature of the valley has rendered this location inappropriate for agricultural purposes since colonial times. The relict of the primitive forest climax saved by this circumstance has expanded gradually to zones whose paedologic conditions favour the eatablishment of mesophilous species. The aerial photograph shows two small stretches of forest, one apparently primi¬tive, the other composed of associations belonging to the subclimax of the subsere. CACHOEIRA FORMATION. Aerial photographs show that this station is crossed by a small river, which divides it into two separate parts. The first, which presents ecological conditions similar, though not identical to those of Batatal, is favoured by topography and apparently remains primitive forest. Though the topography of the other, on the whole, favours the establishment of groups belonging to the normal sere of the climax, is has been partly devastated recently and the aspect of the associations has been completely modified. It was is this part that the four posts for the capturing of mosquitos were set up. The first forest is favoured by deposition of organic matter, washed out from the nearby devasted areas by torrential rains, and thus provides, an appropriate HABITAT for the climax species with certain hygrophilous trends of the ecological quasiclimax type. This association seems to have reached a biological equilibrium, as the dominates. Gallesia gorarema and Cariniana legalis (fig. 10), present an optimum vitality with a vigorous habit and a normal evolutionary cycle. The Cariniantum legalis Gallesiosum equilibrium, corresponds however, to a provisory association, because if the moving of soil by torrential rains should cease it would become possible…

Análise citológica e cariométrica da ação da colchina sôbre a espermatogênese dos hemípteros

The action of colchicine upon the spermatogenesis of Triatoma infestans, (Hemipt. Heteroptera), has been studied and the different categories of giant spermatids that appear during the treatment have been compared with the nuclear volumes of the whole series of normal spermatogenetic stages. The following facts have been ascertained: 1) 4 hours after the treatment the gonial mitotic metaphases, and the 1st. and 2nd. metaphases of meiosis are stopped. The prophasic stages of meiosis and diakynesis appear to be normal. After 9 days of treatment, all the tetrads are broken in the meiotic metaphases and the cells appear with 44 and 22 chromosomes respectively, scattered in the cytoplasm. 2) At 9 days, practically all spermatogenetic stages have disappeared except for a few cysts of spermatogonia, and practically the whole testicle is full of cysts of spermatozoa and spermatid, with some large zones of necrosis with pycnotic nuclei. The spermatids appear to be of different sizes and the statistical analysis of the nuclear volumes gives a polymodal hystogram with 4 modes, whose volumes are in the ratio of 1:2:4:8. Ripe spermatozoa seem to have a certain volume variability, that has not been possible to analyse quantitatively. All these facts confirm what DOOLEY found in the colchicinized Orthoptera testicle. 3) The caryometric analysis conducted statistically on the normal stages of the spermatogenesis (resting spermatogonia, gonial prophases, leptotene, "confused stage", diakynesis, and spermatid) revealed the following facts: a) Considering the volume of the resting, spermatogonia as 1, their mitotic prophases have a volume of 2. Some rare prophases appear to have a volume of 4 and probably belong to tetraployd spermatogonia normally present in the testicle of Hemiptera. b) The first spermatocyte at the beginning of the auxocitary growth (leptotene) has a volume of 2, which is equal to that of them gonial prophase. It grows further during the "confused stage" and reduplicates, reaching thus the volume of 4. Diakynesis has a rather variable nuclear volume and it is higher than volume 4. This is probably of physico-chemical nature and not a growth increase. c) The spermatid at the beginning of the spermiogenetic process has a volume of 1 which is very constant and homogeneous. 4) These results can be summarized concluding that the meiotic process begins from a spermatogonium at the end of his mitotic interphasic growth (vol. 2) and instead of entering into the mitotic prophase transforms itself into the leptotene spermatocyte. During the diplotene ("confused stage") the volume of the nucleus doubles once more and reaches volume 4. In consequence of the two successive meiotic divisions the spermatid, although having an haploid number of chromosomes, has a nuclear volume of 1, just like the diploid spermatogonium. The interpretation of this strange result probably comes from the existence of the "tertiary split" in the chromosomes of the haploid set, that has been illustrated in the Hemiptera by HUGUES SCHRADER and in Orthoptera by MICKEY and co-workers. The tertiary split indicates that the chromosomes of the haploid set are constituted from almost two chromonemata, and this double constitution corresponds to the double cycle of reduplication that takes place during the spermatogenesis starting from the resting gonia. In Triatoma infestans the tertiary split appears in the chromosomes in the 1st. and 2nd. metaphases and in the diakynesis. In the blocked metaphases at the 9th. day of colchicinization some of the 44 elements scattered in the cytoplasm, show, when properly oriented, the split very clearly. Some new and strange facts revealed by SCHRADER and LEUCHTEMBERGER in Arvelius suggest the possibility of other interpretations of the rhythmic growth in special cases. There appears the necessity of more knowledge about the multiple or simple constitution of the chromosomes in somatic and spermatogonial mitosis.

Plancto e hidrobiologia sanitária de tanques tropicais com dáfnias e rotíferos

The engineers of the modern University City are constructing a graceful bridge, named PONTE OSWALDO CRUZ, that crosses a portion of the Guanabara Bay (Fig. 1). The work at west pillar stopped for 3 years (The concret structure in Est. 1). As it will be seen from n.º 1 — 5 of the fig. 1, Est. I, the base of the structure will have five underground boxes of reinforcement, but, to-day they are just like as five uncovered water ponds, until at present: May 1963. (Est. I — fig. 3, n.º 3 — pond n.º 3; A. — old level of the water; B.— actual level of the water; c.— green water; E.— mass of bloom of blue algae Microcystis aeruginosa). Soon after SW portion, as 5 cells in series, of the pillar abutments, and also the NE portion nearly opposite in the Tibau Mount will be filled up with earth, a new way will link Rio City and the University City. We see to day Est. I, fig. 1 — the grasses on the half arenous beach of the Tibau Point. These natural Cyperaceae and Gramineae will be desappear because of so a new road, now under construction, when completed will be 33 feet above the mean sea level, as high as the pillar, covering exactly as that place. Although rainfall was the chief source of water for these ponds, the first water (before meterorological precipitations of whatever first rain it might fall) was a common tap water mixed with Portland Cement, which exuded gradually through the pores of the concret during its hardenning process. Some data of its first cement water composition are on the chemical table, and in Tab. n.º 4 and "Resultado n.º 1". The rain — receiving surface of each pond were about 15 by 16 feet, that is, 240 square feet; when they were full of water, their depth was of 2 feet 3", having each pond about 4,000 gallons. Climatic conditions are obviously similar of those of the Rio de Janeiro City: records of temperature, of precipitation and evaporation are seen on the graphics, figs. 2, 3, 4. Our conceptions of 4 phases is merely to satisfy an easy explanation thus the first phase that of exudation of concrete. We consider the 2nd. phase formation of bacterian and cyanophycean thin pellicel. 3rd. phase - dilution by rains, and fertilisation by birds; the 4th phase - plankton flora and fauna established. The biological material arrived with the air, the rains, and also with contaminations by dusts; with big portion of sand, of earth, and leaves of trees resulted of the SW wind actions in the storming days (See - Est. I, fig. 3, G. - the mangrove trees of the Pinheiro Island). Many birds set down and rest upon the pillar structure, its faeces which are good fertilizers fall into the ponds. Some birds were commonly pigeons, black ravens, swallows, sparrows and other sea mews, moor hens, and a few sea birds of comparatively rare occurence. We get only some examples of tropical dust contaminated helioplankton, of which incipient observations were been done sparcely. See the systematic list of the species of plankters. Phytoplankters - Cyanophyta algae as a basic part for food of zooplankters, represented chiefly by rotiferse, water-fleas Moinodaphnia and other Crustacea: Ostracoda Copepoda and Insecta: Chironomidae and Culicidae larvae. The polysaprobic of septic irruptions have not been done only by heating in summer, and, a good reason of that, for example: when the fifth pond was in polysaprobic phase as the same time an alike septic phase do not happened into the 3rd. pond, therefore, both were in the same conditions of temperature, but with unlike contaminations. Among the most important aquatic organisms used as indicatiors of pollution - and microorganisms of real importance in the field of sanitary science, by authorities of renown, for instance: PALMER, PRESCOTT, INGRAM, LIEBMANN, we choose following microalgae: a) The cosmopolite algae Scenedesmus quadricuada, a common indicator in mesosaprobio waters, which lives between pH 7,0 and it is assimilative of NO[3 subscripted] and NH[4 subscripted]. b) Species of the genus Chlamydomonas; it is even possible that all the species of theses genus inhabit strong-mesosaprobic to polysaprobic waters when in massive blooms. c) Several species of Euglenaceae in fast growing number, at the same time of the protozoa Amoebidae, Vorticellidae and simultaneous with deposition of the decaying cells of the blue algae Anacystis cyanea (= Microcystis) when the consumed oxygen by organic matter resulted in 40 mg. L. But, we found, among various Euglenacea the cosmopolite species (Euglena viridis, a well known polysaprobic indicatior of which presence occur in septic zone. d) Analcystis cyanea (= M. aeruginosa) as we observed was in blooms increasing to the order of billions of cells per litter, its maximum in the summer. Temperatures 73ºF to 82ºF but even 90ºF, the pH higher than 8. When these blue algae was joined to the rotifer Brachionus calyflorus the waters gets a milky appearance, but greenished one. In fact, that cosmopolite algae is used as a mesosaprobic indicator. Into the water of the ponds its predominance finished when the septic polysaprobic conditions began. e) Ankistrodesmus falcatus was present in the 5th pond from 26the. April untill the 26th July, and when N.NH[4 subscripted] gets 1.28 mg. L. and when chlorinity stayed from 0.034 to 0.061 mg. L. It never was found at N.NH[4 subscripted] higher than 1 mg. L. The green algae A. falcatus, an indicatior of pollution, lives in moderate mesosaprobic waters. f) As everyone knows, the rotifer eggs may be widely dispersed by wind. The rotifer Asplanchna brightwelli in our observation seemed like a green colored bag, overcharged by green cells and detritus, specially into its spacious stomach, which ends blindly (the intestine, cloaca, being absent). The stock of Asplanchna in the ponds, during the construction of the bridge "PONTE OSWALDO CRUZ" inhabits alkaline waters, pH 8,0 a 8,3, and when we observed we noted its dissolved oxygen from 3.5 to 4 mg. L. In these ponds Asplanchna lived in 0,2 P.PO[4 subscripted]. (Remember the hydobiological observations foreign to braslian waters refer only from 0.06 to 0,010 mg. L. P.PO[4 subscripted]; and they refer resistance to 0.8 N.NH[4 subscripted]). By our data, that rotiger resist commonly to 1.2 until 1.8 mg. L.N.NH[4 subscripted]; here in our ponds and, when NO[2 subscripted] appears Asplanchna desappears. It may be that Asplanchna were devoured by nitrite resistant animals of by Culicidae or other mosquitoes devoured by Due to these facts the number and the distribution of Asplanchna varies considerabley; see - plates of plankton successions. g) Brachionus one of the commonest members of class Rotatoria was frquently found in abundance into the ponds, and we notice an important biological change produce by the rotifer Brachonus colyciflorus: the occurence of its Brachionus clayciflorus forms pallas, is rare in Brazil, as we know about this. h) When we found the water flea MOinodaphnia we do not record simultanous presence of the blue algae Agmenellun (= Merismopedia).

Tomato response to a high light transmission greenhouse film

Increasing greenhouse light transmission has a positive effect not only in Northern latitudes but in Mediterranean countries as well. A greenhouse, H2, with a tetrafluoroethylene copolymer 60 microns film, (Asahi Glass company, Aflex) characterised by its high light transmission and durability was compared to another greenhouse with a co-extruded film considered as a control, H1. Tomato crop response to the increase in light during winter and summer with high temperature and light was evaluated. Light transmission in H2 remained very high in spite of the observed dust accumulation and the low angle of incidence of the winter solar radiation. Transmissivity was clearly higher for H2 (81 to 83 % throughout the season) than in the control (around 63 %). The rest of the climatic parameters were similar in both greenhouses, either in the winter or in the summer evaluations. In spite of the high solar radiation in H2, the summer temperature could be maintained at the desired levels by using evaporative cooling. Accumulated tomato yield and quality was better in the H2 greenhouse (15 % more for the winter crop and 27% more for the summer crop). Fruit size was bigger in the winter crop. As an overall conclusion, the use of high light transmissive films in Mediterranean areas is very convenient for many vegetable crops. This is valid not only in winter but in summer, provided the greenhouse has good ventilation or evaporative cooling to overcome the increase in sensible heat caused by this increase in light..

Biomphalaria AFF. glabrata do pleistoceno de Janaúba, Minas Gerais

Fossil shells collected during excavations at the extinct Janaúba lake in Minas Gerais, were identified on morphological grounds as Biomphalaria aff. glabrata. Since they were found in a stratigraphic horizon associated with bones of Eremotherium laurillardi (Lund), they can be assumed to belong to the Upper Pleistocene. B. glabrata is presently known to occur on a wide area surrounding the microregion of the "Janaúba lake" but not at the place of the "lake" itself and some kilometers around. The present discontinous distribution can be explained by the Pleistocene-Holocene climatic changes which have occurred in the region.

Ecology of sandflies (Diptera: Psychodidae) in a restricted focus of cutaneous leishmaniasis in Northern Venezuela: III. Seasonal fluctuation

A one year-long study (March 1979-March 1980) was carried out at San Esteban, an endemic focus of cutaneous leishmaniasis in Northern Venezuela, with the aim of observing the seasonal fluctuation of the local phlebotomine sandflies species. The influence of climatic factors (temperature, relative humidity and rainfall) on population dynamics was analyzed in three collecting sites - a house, a peridomestic area and a sylvatic region. Among anthropophilic species, L. panamensis behaved as a wetseason species, the mean minimum relative humidity being the critical factor influencing the total number of individuals. When the population density of this fly decreased, it was successfully replaced by L. ovallesi, a dry-season species. On the other hand, seasonal variations of L. gomezi were more strongly affected by the temperature.

Observações ecológicas sobre Biomphalaria straminea (Dunker, 1848) em áreas do Nordeste, Brasil

The different climatic regions determine the zoogeographic distribution of various animal species depending on their particular conditions and ecological preferences. The host schistosomiasis planorbid is one of these species. This paper deals with the distribution of Biomphalaria straminea in northeast Brazil. It starts from the analysis of different climatic peculiarities in this region, associated to limnological observation done by the author in three different hydric collections in the state of Sergipe. It has been concluded that this is an "eurióioca" species. Its broad ecological valence permits this species to survive in regions where climate asperties are evident, requiring behavior and physiological adaptations. The species survives in all northeast region, from "zona da mata", in the coast, to the semi-arid "sertão".

Augment de la resolució en la reconstrucció de les temperatures de l'aigua i de l'aire del llac Baikal (Sibèria) dels últims 60.000 anys

Aquest estudi consisteix en l’augment de la resolució en la reconstrucció de la temperatura de l’aigua i l’aire del llac Baikal durant els últims 60.000 anys mitjançant l’ús de les proxies de reconstrucció de la temperatura TEX86 i MAAT, i la d’aportació de matèria orgànica d’origen terrestre, el BIT. L’objectiu general d’aquesta investigació és incrementar la resolució temporal en el mostreig del testimoni CON-01-603-02 per tal de millorar el registre de dades obtingudes i d’aquesta manera poder contrastar la hipòtesi de la interconnexió climàtica global, així com identificar esdeveniments climàtics sobtats, tals com els Heinrich events i els esdeveniments D-O. Un cop obtinguts els resultats s’ha realitzat l’anàlisi de la qualitat i fiabilitat de les dades a les resolucions de 5, 10 i 20 Kanys, i es conclou que existeixen diferències globals estadísticament significatives amb els resultats realitzats per Escala et al., (r.n.p [resultats no publicats]), la resolució dels quals es volia augmentar. S’han tractat d’anular aquestes diferències restant o bé sumant la diferència mitjana obtinguda entre les dues mostres en cada un dels intervals de 5 Kanys en què s’han donat aquestes. Els resultats integrats d’Escala et al.,(r.n.p) i els d’aquest estudi, aporten dades que recolzen l’hipòtesi de la interconnexió climàtica global, ja que al comparar-los amb els registres climàtics de Grenlàndia (GRIP2) i l’Antàrtica (Vostok) mostren respostes similars tant per les forces de Milankovitch com per les de subMilankovitch.

Reconstrucció de les temperatures superficials marines dels últims dos milions d'anys al Corrent de Benguela utilitzant l'índex TEX86

Per tal de reconstruir i obtenir una evolució climàtica a partir de les temperatures superficials marines dels últims dos milions d’anys al Corrent de Benguela (costa oest sud-africana) s’han analitzat 60 mostres del testimoni amb ODP 175-1084. Per fer-ho, s’ha utilitzat la nova calibració de l’índex TEX86 (Kim et al., 2007) i s’han representat els resultats juntament amb els valors obtinguts amb altres índexs referents a les temperatures mitjanes anuals de l’aire (MAAT) i el grau d’aportació sedimentària d’origen continental als sediments marins (BIT). També s’han comparat amb els registres de temperatura d’altres estudis en la mateixa àrea obtinguts a partir de proxies diferents. Els resultats del TEX86 mostren certa concordança amb alguns dels valors obtinguts en altres estudis i proposen hipòtesis que relacionen de manera directa els tres índexs calculats.