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Da percepção de riscos à saúde às reais motivações para a conservação da natureza
(202-02) Ribeiro, Servio Pontes; Loyola, Rafael Dias
Vocalizações de algumas espécies do gênero Scinax (Anura, Hylidae) do sudeste do Brasil e comentários taxonômicos
(Universidade Estadual Paulista, 1995) Pombal Júnior, José Perez; Bastos, Rogério Pereira; Haddad, Célio Fernando Baptista
The advertisement calls of Scinax altera, S. argyreornata, S. cuspidata, S. eurydice, S. fuscomarginata, S. fuscovaria, S. hayii, S. rizibilis and S. squalirostris are described. A table with the call parameters of the species in the genus Scinax from Southeastern Brasil is presented. The specific name S. altera is confirmed but is apparently misapplied for several populations. We propose the inclusion of the species from the rizibilis group in the catharinae group, because males of S. trapicheiroi present subgular to lateralized vocal sacs, invalidating the only sinapomorphy of the rizibilis group. Characteristics of vocalization, morphology, and reproductive environment support a generic status for the species in the catharinae group (including rizibilis group).
Spectral decompositions in cluster analysis with applications to limnological data
(Associação Brasileira de Limnologia, 1995-03) Bini, Luis Mauricio; Diniz Filho, José Alexandre Felizola
The establishment of groups based on dendrograms obtained through hierarchical cluster analysis is usually done in arbitrary way. In this paper, it is presented a method to detect at which level of clustering there is a maximization of the correlation between the calculated distance matrix among sampling unities (or operational taxonomic unities – OTUS’s) an a model matrix obtained from the dendrogram. The method is ilustrated by grouping sampling stations of six streams in the state of São Paulo (Brazil) by ten physical-chemical parameters of the water. The final classification obtained is correspondent to the expectation based on the ecological status of the system and its level of pollution.
Geographic variation of africanized honey bees (Apis mellifera L.) in Brazil: multivariate morphometrics and racial admixture
(Sociedade Brasileira de Genética, 1996-06) Diniz Filho, José Alexandre Felizola; Malaspina, Osmar
The correspondence between morphometric and isozymic geographic variation patterns of Africanized honey bees in Brazil was analyzed. Morphometric data consisted of mean vectors of 19 wing traits measured in 42 local populations distributed throughout the country. Isozymic data refer to allelic frequencies of malate dehydrogenase (MDH), and were obtained from Lobo and Krieger (Heredity 68: 44J-448, 1992). The two data sets were analyzed through canonical trend surface, principal cornponents and spatial autocorrelation analyses, and showed north-south clines, demonstrating that Africanized honey bees in southern and southeastern Brazil are more similar to European honey bees than those f􀃸und in northern and northeastern regions. Also, the morphometric variation is within the limits established by the racial admixture model, considering the expected values of Africanized honey bee fore wing length (WL) in southern and northeastern regions of Brazil, estimated by combining average values of WL in the three main subspecies involved in the Africanization process (Apis mellifera scutellata, A. m. ligustica and A. m. mellifera) with racial admixture coefficients.
Nova espécie de Scinax wagler, 1830 do Brasil Central (Amphibia, Anura, Hylidae)
(Museu Nacional (Brasil), 1996-08) Pombal Júnior, José Perez; Bastos, Rogério Pereira
A new species of treefrog of the genus Scinax belonging to the catharinae group is described from Silvânia Municipality, Goiás State, Brasil. It is characterized by snout slightly acuminate in dorsal view and protruding in lateral view; tympanum small; inguinal region and posterior surfaces of thighs with irregular yellow spots on dark brown background, and presence of very developed inguinal glands. A description of vocalizations is provided.
Natural history of three Hydropsychidae (Trichoptera, Insecta) in a “cerrado” stream from northeastern São Paulo state, Brazil
(1996-09) Oliveira, Leandro Gonçalves; Froehlich, Cláudio Gilberto
Diversity and community strcuture of aquatic insects (Ephemroptera, Plecoptera and Trichoptera) in a mountain stream in southeastern Brazil
(1997) Oliveira, Leandro Gonçalves; Froehlich, Cláudio Gilberto
Quantitative analysis of the myelinated axons in the fasciculus gracilis and fasciculus cuneatus. Light microscopy study
(1997) Mata, José Roberto da; Morais, José Oscar Rodrigues; Sabóia-Morais, Simone Maria Teixeira
The fasciculus gracilis and fasciculus cuneatus of the spinal cord of mutant Wistar rats (Rattus norvegicus) were studied by light microscopy at the level of the first and sixth cervical segments in order to determine the extent of myelination at zero, 1, 3, 5, 10, 15, 30 and 120 days of postnatal life. The fasciculus gracilis was found to be practically nonmyelinated at birth, with effective myelination activity starting after the 5th day of age. At the 20th day of age, myelination was more than was more than 50% completed compared to adult 120-day old animals. At birth, the fasciculus cuneatus had myelin fibers and always presented a greater extent of myelination than the fasciculus gracilis at each stage assessed. At the 20th day of age, more than 3/4 of fasciculus cuneatus were myelinated comparing to adult 120-day old animals at level of the first cervical segment. Thus, the myelination of the fasciculus gracilis and fasciculus cuneatus of the spinal cord of mutant Wistar rats was processed as the normal rat, demonstrating that the mutation of
Autocorrelação filogenética para o tamanho do corpo em corujas (Strigiformes) da América do Sul
(Sociedade Brasileira de Ornitologia, 1997-06) Sant'ana, Carlos Eduardo Ramos de; Diniz Filho, José Alexandre Felizola
Developments in the analysis of comparative data indicate that is possible to partition the total variation of a give trait (T) into the phylogenetic component (P), which contains the variance shared by species and indicates the tendency called phylogenetic inertia and a specific component (S), which contains that part of variation that is peculiar to each species. Here, a phylogenetic auto-correlation analysis was used to verify the relative importance of these two components in body size variation of 19 owl (Strigiformes) species from South America, using phylogenetic relationships defines by molecular data. The estimated phylogenetic auto-regressive coefficient p was equal to 0,827, statistically significant at 1% level, and indicates that 68,4% of body size variation in owls (p²) can be atributed to phylogeny and evolutionary constraints. Further studies must take this effect into account to avoid spurious correlations when inferring Darwinian adaptations based solely on relationships betwen oul body size and components os environmental variation, e. g. population density, geographic range, clutch size and population growth rate.
Conceito energético do valor adaptativo e tamanho ótimo do corpo para a avifauna brasileira
(Sociedade Brasileira de Ornitologia, 1997-06) Sant'ana, Carlos Eduardo Ramos de; Diniz Filho, José Alexandre Felizola
Here, Brown's model is used to elucidate the effects of body size on fitness (defined as reproductive power, energy conversion rates for the reproductive process). The model was applied to explain the modal body size for Brazilian birds, and was calculated using data from several authors. Modal body size was between 12 - 20 g for 486 species from 65 families. In the sample, the number of species described per family was correlated significantly with the total number of species in the family (r = 0,96; P < 0,001). Therefore, the modal value is not biased by the irregular distribution of data from species in families with different mean weights. Considering this modal value and assuming C1 = 2.41 Watts, estimated by the allometric relationship of individual productivity as a function of size, we obtained an approximate Co = 0.02 Watt. For mammals, Co and C1 were estimated as 6.0 and 0.2 Watts, respectivel, resulting in a optimal body size of 100 g. Thus, in comparing Co and C1 values of birds and mammals, we conclude that the smaller modal body size of birds may be a function of selection for an equivalent conversion efficiency, which can only be met by a lower body size due to lower values of Co and C1 in birds.
Dinâmica de folhedo em floresta mesófila semidecícua, no município de Araras, SP. II - Fluxo de macronutrientes
(Instituto Florestal de São Paulo, 1997-06) Diniz, Sérgio; Pagano, Sérgio Nereu; Bini, Luis Mauricio
During two consecutive years, monthly macronutrients quantities transferred from the vegetation to the soil via fine litter were estimated in an area of mesophytic semideciduous forest located at municipality of Araras (42°23WG, 22°18'S) in the State of São Paulo, Brazil. The levels of macronutrients were much higher in the leaf litter than into twigs, flowers and fruits pointly analised fractions litter. For the litter leafs macronutrient quantities followed the order: N > Ca > K > Mg > S > P, while for the remaining fractions the order was Ca > N > K > S > Mg > P. The values for macronutrients in the leaves were significatively higher than the ones for the remaining fractions of litter (twigs, flowers and fruits). The macronutrient quantities (kg/ha) transferred year to year through the production of fine litter were: N = 230.0; Ca = 230.0; K = 79.0; Mg = 30.0; S = 27.0; P= 8.0.
Ecologia de comunidades de insetos bentônicos (Ephemeroptera, Plecoptera e Trichoptera), em córregos do Parque Ecológico de Goiânia, Goiás, Brasil
(1997-12) Oliveira, Leandro Gonçalves; Bispo, Pitágoras da Conceição; Sá, Nívia Custódio de
Relationships among some abiotic factors (temperature, velocity, tlow, conductivity, oxy-reduction potential and pl-l) and the seazonal density ofbenthic insects (immature forms) of lhe orders Ephemeroplera, Plecoplera and Trichoptera at the Parque Ecológico de Goiânia, Goiás are studied. An area of 1m2 was sampled and abiotic factors were recorded in 4 sites fram August/I994 to July/1995. The faunistic composition was 75% Ephemeraplera, 1% Plecoptera and 24% Trichoplera. The data suggest the water velocity and tlow as lhe 11lain faclors that delennined the aquatic insects abundance.
Ecologia e manejo de macrófitas aquáticas em reservatórios
(Associação Brasileira de Limnologia, 1998-03) Thomaz, Sidinei Magela; Bini, Luis Mauricio
The increased growth of aquatic macrophytes and the weed problems which they can cause in reservoirs has drawn the attention of researchers and hydroelectric environmental technicians. Here we address some theoretical issues about reservoir colonization by aquatic macrophytes. Local processes (nutrient inputs, margin development, slope, depth, light penetration, water level fluctuation and biological succession processes), together with regional processes (regional species pool, dispersion and invasion rates by non-native species) are among the main factors that control species composition and abundance. Excessive aquatic vegetation growth is promoted mainly by environmental shifts following reservoir construction. This situation is intensified when species are introduced. The generally-high tolerance of disturbance by aquatic macrophytes (resulting from their commonly-held biological characteristics of high dispersion capacity, colonization and regrowth, high growth rates, high phenotypic plasticity and existence of dormancy) allows them to resist weed control efforts quite well. The traditional control methhods (chemical, mechanical and biological) are often of limited efficiency in large freshwater systems. The lack of basic ecological studies and the lack of monitoring are also factors which explain the low efficiency of such methods.
Nova espécie de Hyla laurenti, 1768 do centro-oeste brasileiro e a posição taxonômica de H. Microcephala werneri cochran, 1952 e H. Microcephala meridiana B. Lutz, 1952 (Anura, Hylidae)
(Museu Nacional (Brasil), 1998-07) Pombal Júnior, José Perez; Bastos, Rogério Pereira
A new species of treefrog of the genus Hyla belonging to the H. microcephala group is described from Silvânia municipality, Goiás State, Brazil. It is characterized by small size (SVL 16.3-19.4mm in males); head slightly longer than wide; tympanum small and not much visible; supratimpanic fold undeveloped; absence of dorsal colar pattern with white lateral stripes; advertisement call with only one note type composed by two pulses. Notes on the natural history anel description of the advertisement call are provided. Hyla microcephala werneri Cochran and H. m. meridiana B. Lutz are considered full species. The advertsiment call of H. meridiana is described.
Hierarchical effects on body size evolution and the macroecology of South American rainforest mammals
(1998-10) Diniz Filho, José Alexandre Felizola; Balestra, Rackel
The relationship between geographic range size and body size analyzed at the continental scale for many species has been described recently by an envelope region defined in bivariate space and limited by ecological and physical constraints. These constraints can be explained by stochastic extinction related to m inimum population density and energetic theories for an optimal body size. However, since data are obtained for different species in a large taxonomic group, it is possible that these variables may be strongly affected by phylogenetic autocorrelation. In this paper, we analyzed data on geographic range size and body size for 87 species of Neotropical rainforest mammals from South America, searching for phylogenetic effects changing the shape of constraint space. We used a nested ANOVA design to evaluate and remove large scale hierarchical (phylogenetic) trends in the two variables. Body size was more affected by phylogenetic effects than geographic range size. After removing these effects, we noted that the two macroecological variables analyzed support the shape of constraint space previously observed in North American species. The most important aspect of our analyses is that a model for optimal body size related to life-history variations provides an useful theoretical framework to understand how processes of species dynamics can lead to the observed macroecological patterns.
Padrões e processos na evolução do tamanho do corpo em carnívoros (mammalia) da América do Sul
(Instituto Internacional de Ecologia, 1998-11) Diniz Filho, José Alexandre Felizola; Vieira, Cleiber Marques
In the last few years, many models have been proposed to link microevolutionary processes to macroevolutionary patterns, defined by comparative data analysis. Among these, Brownian motion and Ornstein-Uhlenbeck (O-U) processes have been used to model, respectively, genetic drift and stabilizing selection. Since these models produce different curves of pairwise variance between species against time since divergence, different profiles in phylogenetic correlograms must appear. In this paper, we analyzed variation in body weight among 17 species of South American carnivores by means of phylogenetic correlograms, constructed using Moran’s I coefficients in four distance classes. Phylogeny among species was based on molecular data. The observed correlogram was then compared with 400 simulated correlograms of Brownian motion and O-U over the same phylogeny. The observed correlogram indicates a phylogenetic gradient up to 8 mya, when coefficients tend to stabilize, and autoregressive model indicates that around 74% of the interspecific variance in body size can be explained by phylogenetic inertia. This is expected by considering that body size is usually correlated with many ecological and lifehistory traits, being subjected to many constraints that can be modeled by O-U process expressing stabilizing selection.
Distribuições de categorias funcionais alimentares de larvas de Trichoptera (Insecta) em uma região serrana do Brasil central
(1999) Oliveira, Leandro Gonçalves; Bispo, Pitágoras da Conceição; Crisci, V. L.; Souza, K. G.
Aquatic macrophytes of Itaipu Reservoir, Brazil: survey of species and ecological considerations
(Instituto de Tecnologia do Paraná - Tecpar, 1999-01) Thomaz, Sidinei Magela; Bini, Luis Mauricio; Souza, Maria Conceição de; Kita, Kazue Kawakita; Camargo, Antonio Fernando Monteiro
Atividade reprodutiva de Scinax rizibilis (Bokermann)(Anura, Hylidae) na Floresta Atlântica, sudeste do Brasil
(Sociedade Brasileira de Zoologia, 1999-06) Bastos, Rogério Pereira; Haddad, Célio Fernando Baptista
The breeding activity of Scinax rizibilis (Bokermann, 1964) was observed in a temporary pond, in the municipality of Ribeirão Branco, in the Southern São Paulo State from February 1993 to January 1994 and November 1994 to February 1995. The reproductive season extended from September to February. Females were larger and heavier (after oviposition) than males. ln the chorus, the spatial distribution tended towards uniformity. The number of males and females in the chorus was positively correlated. However therewas no correlation between the number of males and the estimation of the operational sex ratios. On average there were seven males for each female present in the chorus. The males were apparently selected by females.
Macroecologia de corujas (Aves: Strigiformes) da América do Sul
(Sociedade Brasileira de Ornitologia, 1999-06) Sant'Ana, Carlos Eduardo Ramos de; Diniz Filho, José Alexandre Felizola
Macroecology is the study of the relationships among ecological variables in large scales of space and time. ln this paper, the macroecological relationship between body size and geographic range size was analyzed for 29 species of South American owls (Strigiformes). This relationship followed the Brown and Maurer model (1987, 1989), characterized by a triangular region in bivariate space, with the minimum geographic range size being positively correlated with body length. This is an expected association because large species require more energy and must use a larger arca of the environment. On the other hand, small geographic ranges imply higher intraspecific compelition, low local population density and, therefore, a higher probability of extinction. However, since species do not usually provide independent observations in a statistical analysis because they share characteristics through descent from common ancestors, at distinct leveis, it is necessary to control these effects in rnacroecological data. For this study, phylogenetic relationships among specics were based on the cladogram provided by Sibley and Ahlquist ( 1990), constructed using DNA-DNA hybridization. The control of these phylogenetic effects from cross-species data was done using the phylogenetic autocorrelation analysis (correlograms and the autoregressive model), that indicated strong phylogenetic autocorrelation in body size. The correlation between body size and geographic range size for South American owls is signiticant at the 1% level after controlling the phylogenetic effects. Thus, we conclude that this positive relationship must he interpreted as a real ecological process and not as the by-product of phylogenetic inertia in each of the characters.

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