37 research outputs found
O som ao redor: leituras, memĂłria e ruĂna
Tese (doutorado)- Universidade Federal de Santa Catarina, Centro de Comunicação e ExpressĂŁo, Programa de PĂłs-Graduação em Literatura, FlorianĂłpolis, 2017.O objetivo da tese Ă© propor modos de leitura para o filme O som ao redor. A anĂĄlise Ă© realizada a partir das noçÔes de arquivo, tempo e imagem, formando uma teia literĂĄria de suporte para pensar a complexidade do filme. Para lançar hipĂłteses de leitura e interpretação para o filme mapeamos textos filosĂłficos, sociolĂłgicos e poĂ©ticos, que se conectam para pensar as relaçÔes residuais da casa grande no subĂșrbio de Recife. Forma-se uma teia de apoio teĂłrico-crĂtica para pensar a complexidade do filme do qual se seleciona personagens-chave (Bia e Francisco) e figuras imagĂ©ticas recorrentes (a grade e a espiral) para nos auxiliar a perceber as passagens e as descontinuidades nos gestos (do antigo ao novo, da manufatura ao industrial) dos tempos (do arcaico ao atual) e dos contextos (regional ao global, das cenas enquadradas Ă s contĂnuas). No filme estudado, a narrativa se desenvolve pela conexĂŁo espiralada dos fatos, assim, percebemos as idas e vindas do tempo, trazendo as transformaçÔes na passagem passado/presente na memĂłria de uma açucarocracia, cujo impacto se sente nos dias de hoje.Abstract : The objective of this thesis is to propose modes of reading the film O Som ao Redor. The analysis is made having in mind the notions of archive, time and image, in order to form a literary net which allows us to think about the complexity of this film. In order to interpret it we map some philosophical, some sociological and some poetic texts which interconnect so that it is possible to notice the residual relations between the Masters and the Slaves in the suburbs of Recife. A network of both critical and theoretical support is then created to think the film?s complex editing. Key-charcaters (Bia and Francisco) and imagetical figures which are recurrent, respectively, the square and the spiral, help us to perceive the passages and the discontinuities in gestures (from the old one to the new, from manufacture to industrial) difference in times (from the archaic to the present) and contexts (regional/global, square scenes do continuous). In this film, narrative develops itself by the spiraled connections of facts, and thus we can perceive the tos and fros in time, bringing transformations in the bygones of a sugar-cane aristocracy whose impacts are felt today
Spatial memory in the grey mouse lemur (Microcebus murinus)
Wild animals face the challenge of locating feeding sites distributed across broad spatial and temporal scales. Spatial memory allows animals to find a goal, such as a productive feeding patch, even when there are no goal-specific sensory cues available. Because there is little experimental information on learning and memory capabilities in free-ranging primates, the aim of this study was to test whether grey mouse lemurs (Microcebus murinus), as short-term dietary specialists, rely on spatial memory in relocating productive feeding sites. In addition, we asked what kind of spatial representation might underlie their orientation in their natural environment. Using an experimental approach, we set eight radio-collared grey mouse lemurs a memory task by confronting them with two different spatial patterns of baited and non-baited artificial feeding stations under exclusion of sensory cues. Positional data were recorded by focal animal observations within a grid system of small foot trails. A change in the baiting pattern revealed that grey mouse lemurs primarily used spatial cues to relocate baited feeding stations and that they were able to rapidly learn a new spatial arrangement. Spatially concentrated, non-random movements revealed preliminary evidence for a route-based restriction in mouse lemur space; during a subsequent release experiment, however, we found high travel efficiency in directed movements. We therefore propose that mouse lemur spatial memory is based on some kind of mental representation that is more detailed than a route-based network map
Small-scale coexistence of two mouse lemur species (Microcebus berthae and M. murinus) within a homogeneous competitive environment
Understanding the co-occurrence of ecologically similar species remains a puzzling issue in community ecology. The species-rich mouse lemurs (Microcebus spec.) are distributed over nearly all remaining forest areas of Madagascar with a high variability in species distribution patterns. Locally, many congeneric species pairs seem to co-occur, but only little detailed information on spatial patterns is available. Here, we present the results of an intensive captureâmarkârecapture study of sympatric Microcebus berthae and M. murinus populations that revealed small-scale mutual spatial exclusion. Nearest neighbour analysis indicated a spatial aggregation in Microcebus murinus but not in M. berthae. Although the diet of both species differed in proportions of food categories, they used the same food sources and had high feeding niche overlap. Also, forest structure related to the spatial distribution of main food sources did not explain spatial segregation because parts used by each species exclusively did not differ in density of trees, dead wood and lianas. We propose that life history trade-offs that result in species aggregation and a relative increase in the strength of intra-specific over inter-specific competition best explain the observed pattern of co-occurrence of ecologically similar congeneric Microcebus species
Networks in Auxology: proceedings of the 31st Aschauer Soiree, held at Aschau, Germany, June 17th 2023
Thirty-four scientists met for the annual Auxological conference held at Aschau, Germany, to particularly discuss the interaction between social factors and human growth, and to highlight several topics of general interest for the regulation of human growth. Humans are social mammals. We show and share personal interests and needs, and we are able to strategically adjust size according to social position, with love and hope being prime factors in the regulation of growth. In contrast to Western societies, where body size has been shown to be an important predictor of socioeconomic status, egalitarian societies without formalized hierarchy and material wealth-dependent social status do not appear to similarly integrate body size and social network. Social network structures can be modeled by Monte Carlo simulation. Modeling dominance hierarchies suggests that winner-loser effects play a pivotal role in robust self-organization that transcends the specifics of the individual. Further improvements of the St. Nicolas House analysis using re-sampling/bootstrap techniques yielded encouraging results for exploring dense networks of interacting variables. The D-score scale, the Infancy-Childhood-Puberty (ICP) growth model and the SuperImposition by Translation And Rotation (SITAR) technique were presented, as well as customized pediatric growth references, and approaches towards a Digital Rare Disease Growth Chart Library. First attempts with a mobile phone application were presented to investigate the associations between maternal pre-pregnancy overweight, gestational weight gain, and the childâs future motor development. Clinical contributions included growth patterns of individuals with Silver-Russell syndrome, and treatment burden in children with growth hormone deficiency. Contributions on sports highlighted the fallacy inherent in disregarding the biological maturation status when interpreting physical performance outcomes. The meeting explored the complex influence of nutrition and lifestyle on menarcheal age of Lithuanian girls and emphasized regional trends in height of Austrian recruits. Examples of the psychosocial stress caused by the forced migration of modern Kyrgyz children and Polish children after World War II were presented, as well as the effects of nutritional stress during and after World War I. The session concluded with a discussion of recent trends in gun violence affecting children and adolescents in the United States, and aspects of life history theory using the example of âBorderline Personality Disorder.â The features of this disorder are consistent with the notion that it reflects a âfastâ life history strategy, with higher levels of allostatic load, higher levels of aggression, and greater exposure to both childhood adversity and chronic stress. The results were discussed in light of evolutionary guided research. In all contributions presented here, written informed consent was obtained from all participants in accordance with institutional Human investigation committee guidelines in accordance with the Declaration of Helsinki amended October 2013, after information about the procedures used
Ăkologische Determinanten von Sozialsystemen: vergleichende und experimentelle Nahrungsökologie von zwei Mausmaki-Arten (<i>Microcebus berthae, M. murinus</i>)
Ein grundlegendes Modell zur Evolution von
Sozialsystemen ist das sozioökologische Modell (SEM),
welches Vorhersagen ĂŒber kausale ZusammenhĂ€nge zwischen
der VariabilitÀt in der Verteilung von Ressourcen, des
resultierenden Konkurrenz-Regimes und der sozialen
Organisation und Sozialstruktur macht. Die DiversitÀt
der Gesellschaftsformen von SĂ€ugetieren wurde bisher
vorwiegend an gruppenlebenden Arten untersucht,
wohingegen VariabilitÀt in Sozialsystemen solitÀrer
Arten jedoch noch wenig verstanden ist. Das generelle
Ziel der vorliegenden Arbeit war es, Vorhersagen des
SEM zur Evolution von Sozialsystemen vergleichend an
zwei nah verwandten sympatrischen solitÀren
Mausmaki-Arten (Microcebus berthae und M. murinus) zu
ĂŒberprĂŒfen. Beide Arten weisen groĂe Ăhnlichkeiten in
grundlegenden life history- und sozialen Merkmalen auf,
unterscheiden sich aber deutlich in den rÀumlichen und
zeitlichen Verteilungsmustern der Weibchen. Seit Beginn
dieser Langzeitstudie im August 2002 habe ich in einem
Untersuchungsgebiet von 25ha im ForĂȘt de Kirindy/CFPF
(West-Madagaskar) 177 M. berthae und 291 M. murinus
sympatrischer Populationen regelmĂ€Ăig gefangen,
vermessen und markiert. In 22 Monaten Feldaufenthalt
zwischen MĂ€rz 2004 und November 2007 wurden in ĂŒber
1700h Fokustierbeobachtung und Radiotelemetrie Daten
zur Raumnutzung und zum Verhalten fĂŒr 18 M. berthae und
17 M. murinus Weibchen gesammelt. Die Nahrungsökologie
beider Arten habe ich mit Hilfe direkten Beobachtungen,
Kotanalysen und der Analyse stabiler Stickstoff- und
Kohlenstoff-Isotopen untersucht. GanzjÀhrige
regelmĂ€Ăige phĂ€nologische Aufnahmen und standardisierte
FÀnge von Arthropoden erlaubten eine AbschÀtzung der
relativen RessourcenverfĂŒgbarkeit im Habitat. Die
wesentlichen Ergebnisse dieser Studie entsprechen den
Vorhersagen des SEM. Sie zeigen, dass die
Ressourcenverteilung und daraus resultierende
Konkurrenz-Regimes Unterschiede in der rÀumlichen und
zeitlichen Verteilung und der Sozialstruktur von
solitÀren Arten erklÀren können. Dies konnte zusÀtzlich
durch ein Feldexperiment bestÀtigt werden, in welchem
Weibchen adaptiv auf manipulierte Nahrungsverteilung
reagierten. Die Hauptnahrungsquellen von M. berthae
sind klein und dispers verteilt, was starke
Ausbeutungskonkurrenz begĂŒnstigt und zur rĂ€umlichen
Vermeidung von Weibchen fĂŒhrt. Im Gegensatz dazu nutzen
M. murinus vorwiegend geklumpt verteilte, höherwertige
(groĂe) Ressourcen. Diese Ressourcen sind
monopolisierbar und begĂŒnstigen Interferenzkonkurrenz
zwischen oder innerhalb von Gruppen, was rÀumliche
Assoziationen von Weibchen ermöglicht. ZusÀtzlich hat
auch die RessourcenverfĂŒgbarkeit einen wichtigen
Einfluss auf die rÀumliche und zeitliche Verteilung von
Weibchen. Wegen groĂer Unterschiede in der
Nahrungsnischenbreite und in der Art von Strategien,
mit denen sie Zeiten von Nahrungsknappheit ĂŒberstehen,
sind Weibchen beider Arten davon unterschiedlich stark
beeinflusst. WĂ€hrend M. murinus Weibchen saisonal
inaktiv sind und vorhandene Nahrung opportunistisch
nutzen, sind spezialisierte M. berthae Weibchen
saisonaler Nahrungsknappheit stÀrker ausgesetzt, was
die rÀumliche Dispersion von Weibchen weiter erhöht. Da
beide Arten groĂe Ăhnlichkeiten in ihrer
Nahrungsökologie und ihren HabitatansprĂŒchen haben,
besteht ĂŒberdies zwischen-artliche Konkurrenz, was sich
negativ auf die NahrungsverfĂŒgbarkeit fĂŒr kleinere M.
berthae Weibchen auswirkt und kleinrÀumig zu
gegenseitigem Ausschluss beider Arten fĂŒhrt. Lokale und
regionale Koexistenz wird jedoch durch life-history
trade-offs stabilisiert, die ein kleinrÀumliches Muster
von Aggregationen der einen oder anderen Art bedingen.
Zusammenfassend wurden mit dieser Arbeit vergleichende
und experimentelle Daten ĂŒber solitĂ€re Primaten
erhoben, die es ermöglichten existierende
sozioökologische Theorien auf solitÀre Arten zu
ĂŒbertragen und ein neueres Modell zur Koexistenz
ökologisch Àhnlicher Arten empirisch zu testen.The socio-ecological model (SEM) integrates
ecological factors with characteristics of social
systems and allows predictions about the relationships
between resource distribution, type of competition and
consequences for social organization and structure.
Both theoretical and empirical research within this
framework has mainly focused on explaining the
evolution and maintenance of variation among
group-living primates and other mammals. The main aim
of this thesis was to illuminate ecological
determinants of variation in the social organization
and structure of solitary species, which exhibit yet
unexplained diversity in these variables. I studied two
nocturnal solitary primates (Microcebus berthae, M.
murinus), which differ in two characteristics of female
associations: (1) ranging patterns and (2) sleeping
associations. Beginning in August 2002, I monitored
individuals of sympatric populations in a 25ha study
area in Kirindy Forest/CFPF (Madagascar) and (re-)
captured and marked a total of 177 M. berthae and 291
M. murinus. Between March 2004 and November 2007, I
recorded data on spatial patterns and behaviour of 18
M. berthae and 17 M. murinus females by means of direct
observation and radio-tracking in more than 1700 hours.
I quantified intra-specific differences in diet based
on feeding behaviour, analysis of faecal samples, and
stable nitrogen and carbon isotope analysis of hair and
potential food sources. Relative resource availability
was assessed by year-round phenological monitoring of
trees and standardized capture of arthropods from
different guilds. The main results supported basic
predictions of the SEM and revealed that resource
characteristics and the resulting competitive regimes
did indeed relate to differences in female
spatial-temporal patterns and social structure of
solitary foragers. The major food sources of M. berthae
occurred in small dispersed patches, leading to strong
within-group scramble competition and over-dispersed
females with a low potential for female associations.
In contras t, M. murinus also used patchily
distributed, high quality (large) resources. Within and
between-group contest competition over these
monopolizable resources allowed females of this species
to cluster in space. When food distribution was
experimentally manipulated, females of both species
flexibly adjusted their spatial patterns. Moreover,
food availability was identified as a major determinant
of female spatial-temporal patterns, which affected
these mouse lemur species unequally, mainly due to
pronounced differences in feeding niche width and
energy strategies to survive the lean season. In
contrast to opportunistically feeding and seasonally
inactive M. murinus, the more specialized M. berthae
females experienced seasonally low food density, which
enhanced female spatial avoidance. In addition,
inter-specific competition between these ecologically
similar mouse lemurs added substantial variation to the
relative availability of resources for M. berthae and
M. murinus females, respectively. Nevertheless, spatial
competitive coexistence is possible due to life history
trade-offs that result in species aggregation and a
relative increase in the strength of intra-specific
over inter-specific competition. In conclusion, the
present study successfully applied existing
socio-ecological theory to solitary foragers, tested a
recent model on competitive coexistence and contributed
a comparative data set to our understanding of
inter-specific behavioural and ecological variation in
solitary foragers
The Bruce effect revisited : is pregnancy termination in female rodents an adaptation to ensure breeding success after male turnover in low densities?
Pregnancy termination after encountering a strange male, the Bruce effect, is regarded as a counterstrategy of female mammals towards anticipated infanticide. While confirmed in caged rodent pairs, no verification for the Bruce effect existed from experimental field populations of small rodents. We suggest that the effect may be adaptive for breeding rodent females only under specific conditions related to populations with cyclically fluctuating densities. We investigated the occurrence of delay in birth date after experimental turnover of the breeding male under different population composition in bank voles (Myodes glareolus) in large outdoor enclosures: one-maleâmultiple-females (n = 6 populations/18 females), multiple-malesâmultiple-females (n = 15/45), and single-maleâsingle-female (MF treatment, n = 74/74). Most delays were observed in the MF treatment after turnover. Parallel we showed in a laboratory experiment (n = 205 females) that overwintered and primiparous females, the most abundant cohort during population lows in the increase phase of cyclic rodent populations, were more likely to delay births after turnover of the male than year-born and multiparous females. Taken together, our results suggest that the Bruce effect may be an adaptive breeding strategy for rodent females in cyclic populations specifically at low densities in the increase phase, when isolated, overwintered animals associate in MF pairs. During population lows infanticide risk and inbreeding risk may then be higher than during population highs, while also the fitness value of a litter in an increasing population is higher. Therefore, the Bruce effect may be adaptive for females during annual population lows in the increase phases, even at the costs of delaying reproduction.peerReviewe
Data from: Broad and flexible stable isotope niches in invasive non-native Rattus spp. in anthropogenic and natural habitats of central eastern Madagascar
Background: Rodents of the genus Rattus are among the most pervasive and successful invasive species, causing major vicissitudes in native ecological communities. A broad and flexible generalist diet has been suggested as key to the invasion success of Rattus spp. Here, we use an indirect approach to better understand foraging niche width, plasticity, and overlap within and between introduced Rattus spp. in anthropogenic habitats and natural humid forests of Madagascar. Results: Based on stable carbon and nitrogen isotope values measured in hair samples of 565 individual rodents, we found that R. rattus had an extremely wide foraging niche, encompassing the isotopic space covered by a complete endemic forest-dwelling Malagasy small mammal community. Comparisons of Bayesian standard ellipses, as well as (multivariate) mixed-modeling analyses, revealed that the stable isotope niche of R. rattus tended to change seasonally and differed between natural forests and anthropogenic habitats, indicating plasticity in feeding niches. In co-occurrence, R. rattus and R. norvegicus partitioned feeding niches. Isotopic mismatch of signatures of individual R. rattus and the habitat in which they were captured, indicate frequent dispersal movements for this species between natural forest and anthropogenic habitats. Conclusions: Since R. rattus are known to transmit a number of zoonoses, potentially affecting communities of endemic small mammals, as well as humans, these movements presumably increase transmission potential. Our results suggest that due to their generalist diet and potential movement between natural forest and anthropogenic habitats, Rattus spp. might affect native forest-dependent Malagasy rodents as competitors, predators, and disease vectors. The combination of these effects helps explain the invasion success of Rattus spp. and the detrimental effects of this genus on the endemic Malagasy rodent fauna
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Investigating behavior and ecology of Aphaenogaster swammerdami (Formicidae) in selectively logged forest: 20 years later â a happy ant?
The impacts of logging have been widely studied at the community level, describing changes in species composition and richness, whereas the small-scale effects on behavior and ecology of single species have received less attention. We investigated whether the Malagasy wood ant Aphaenogaster swammerdami exhibits differences in colony density, colony size, and feeding ecology between three different sites within the Kirindy Forest (CNFEREF), a dry deciduous forest in central western Madagascar. Specifically, we compared undisturbed primary forest, a selectively logged area, and one site exposed to natural disturbance caused by an adjacent river. Transect surveys were used to record colony density as
well as diameter of the mound as a predictor of colony size. Focal colonies were selected at all three sites
to assess other aspects of colony size, i.e. the number and size of workers and the home range area. The
feeding ecology of ants from all three sites was compared by using observational records on food quality
and quantity, as well as stable isotope analyses of ant workers. We found that in selectively logged forest,
colony density was lower and colony size larger than at the two other sites. Feeding behavior differed
slightly, as colonies from selectively logged forest had a higher intake of animal food sources. Thus, we
tentatively conclude that A. swammerdami, despite its opportunistic lifestyle, still exhibits responses to
selective logging, which took place 20 years ago. Replicating these findings on a larger scale and determining the specific mechanisms leading to changes in lifestyle along disturbance gradients should be the
focus of future studies