NONINVASIVE MONITORING OF ANDROGENS IN MALE AMAZONIAN MANATEE (TRICHECHUS INUNGUIS): BIOLOGIC VALIDATION

The Amazonian manatee (Trichechus inunguis) is endemic in the Amazonian basin and is the only exclusively fresh water sirenian. Historically hunted on a large scale, this species is now considered endangered, and Studies on the reproductive physiology are critical for the improvement of reproductive management of captive and wild Populations of manatees. The aim of this Study was to verify the viability of androgen measurement in saliva, lacrimal, urine, and fecal samples of the Amazonian manatee by conducting a hormone challenge. Two adult male manatees (A-1 and A-2) were Submitted to an experimentation protocol of 12 day (D1 to D10). On D0, the animals received an intramuscular injection of gonadotropin-releasing hormone (GnRH)-analogue. Salivary, lacrimal, urinary, and fecal samples were collected daily (between 0800 hours and 0900 hours) and frozen at -20 degrees C until assayed. Fecal samples were lyophilized, extracted with 80% methanol, and diluted in buffer before the radioimmunoassay (RIA). Urine samples underwent acid hydrolysis and were diluted in depleted bovine serum. Salivary and lacrimal samples were assayed without the extraction step. Hormonal assays were conducted with a commercial testosterone RIA kit. An androgen peak (>median + 2 interquartile range [IQR]) was observed in all matrices of both animals, although it was less prominent in the lacrimal samples of A-2. However, the fecal androgen peak (A-1 peak = 293.78 ng/g dry feces, median [IQR] = 143.58 [32.38] ng/g dry feces; A-2 peak = 686.72 ng/g dry feces, median [IQR] = 243.82 [193.16] ng/g dry feces) occurred later than urinary (A-1 peak = 648.16 ng/mg creatinine [Cr], median [IQR] = 23.88 [30.44] ng/mg Cr; A-2 peak = 370.44 ng/mg Cr, median [IQR] = 113.87 [117.73] ng/mg Cr) and salivary (A-1 peak = 678.89 pg/ml, median [IQR] = 103.69 [119.86] pg/ml; A-2 peak = 733.71 pg/ml, median [IQR] = 262.92 [211.44] pg/ml) androgen peaks. These intervals appear to be correlated with the long digesta passage time in this species. The salivary and urinary peaks were closely associated. These results demonstrate that androgen concentrations in saliva, urine, or feces samples reflect reliably physiologic events and are a powerful tool for noninvasive reproductive monitoring of Amazonian manatees.

Dam worms

Human and animal infection rates with the Oriental schistosome have steadily declined in China over the last half-century, but the Three Gorges Dam may reverse this decline by creating new, or enlarging existing, ideal environments for the worm and its aquatic snail intermediate host.

Ontogenetic changes of swimming kinematics in a semi-aquatic reptile (Crocodylus porosus)

Semi-aquatic animals represent a transitional locomotor condition characterised by the possession of morphological features that allow locomotion both in water and on land. Most ecologically important behaviours of crocodilians occur in the water, raising the question of whether their 'terrestrial construction' constrains aquatic locomotion. Moreover, the demands for aquatic locomotion change with life-history stage. It was the aim of this research to determine the kinematic characteristics and efficiency of aquatic locomotion in different-sized crocodiles (Crocodylus porosus). Aquatic propulsion was achieved primarily by tail undulations, and the use of limbs during swimming was observed only in very small animals or at low swimming velocities in larger animals. Over the range of swimming speeds we examined, tail beat amplitude did not change with increasing velocity, but amplitude increased significantly with body length. However, amplitude expressed relative to body length decreased with increasing body length. Tail beat frequency increased with swimming velocity but there were no differences in frequency between different-sized animals. Mechanical power generated during swimming and thrust increased non-linearly with swimming velocity, but disproportionally so that kinematic efficiency decreased with increasing swimming velocity. The importance of unsteady forces, expressed as the reduced frequency, increased with increasing swimming velocity. Amplitude is the main determinant of body-size-related increases in swimming velocity but, compared with aquatic mammals and fish, crocodiles are slow swimmers probably because of constraints imposed by muscle performance and unsteady forces opposing forward movement. Nonetheless, the kinematic efficiency of aquatic locomotion in crocodiles is comparable to that of fully aquatic mammals, and it is considerably greater than that of semi-aquatic mammals.

Sustained swimming performance in crocodiles (Crocodylus porosus): Effects of body size and temperature

We examined effects of body size and temperature on swimming performance in juvenile estuarine crocodiles, Crocodylus porosus, over the size range of 30-110 cm total body length. Swimming performance, expressed as maximum sustainable swimming speed, was measured in a temperature- and flow-controlled swimming flume. Absolute sustainable swimming speed increased with body length, but length-specific swimming performance decreased as body length increased. Sustained swimming speed increased with temperature between 15degreesC and 23degreesC, remained constant between 23degrees and 33degreesC, and decreased as temperature rose above 33degreesC. Q(10)-values of swimming speed were 2.60 (+/- 0.091 SE) between 18degreesC and 23degreesC, and there were no differences in Q(10) between crocodiles of different sizes. The broad plateau of thermal independence in swimming speed observed in C. porosus may be of adaptive significance by allowing dispersal of juvenile animals at suboptimal body temperatures.

Water quality issues in rivers, lakes and reservoirs in Asian countries: an approach to the problems and the methodologies

Water covers over 70% of the Earth's surface, and is vital for all known forms of life. But only 3% of the Earth's water is fresh water, and less than 0.3% of all freshwater is in rivers, lakes, reservoirs and the atmosphere. However, rivers and lakes are an important part of fresh surface water, amounting to about 89%. In this Master Thesis dissertation, the focus is on three types of water bodies – rivers, lakes and reservoirs, and their water quality issues in Asian countries. The surface water quality in a region is largely determined both by the natural processes such as climate or geographic conditions, and the anthropogenic influences such as industrial and agricultural activities or land use conversion. The quality of the water can be affected by pollutants discharge from a specific point through a sewer pipe and also by extensive drainage from agriculture/urban areas and within basin. Hence, water pollutant sources can be divided into two categories: Point source pollution and Non-point source (NPS) pollution. Seasonal variations in precipitation and surface run-off have a strong effect on river discharge and the concentration of pollutants in water bodies. For example, in the rainy season, heavy and persistent rain wash off the ground, the runoff flow increases and may contain various kinds of pollutants and, eventually, enters the water bodies. In some cases, especially in confined water bodies, the quality may be positive related with rainfall in the wet season, because this confined type of fresh water systems allows high dilution of pollutants, decreasing their possible impacts. During the dry season, the quality of water is largely related to industrialization and urbanization pollution. The aim of this study is to identify the most common water quality problems in Asian countries and to enumerate and analyze the methodologies used for assessment of water quality conditions of both rivers and confined water bodies (lakes and reservoirs). Based on the evaluation of a sample of 57 papers, dated between 2000 and 2012, it was found that over the past decade, the water quality of rivers, lakes, and reservoirs in developing countries is being degraded. Water pollution and destruction of aquatic ecosystems have caused massive damage to the functions and integrity of water resources. The most widespread NPS in Asian countries and those which have the greatest spatial impacts are urban runoff and agriculture. Locally, mine waste runoff and rice paddy are serious NPS problems. The most relevant point pollution sources are the effluents from factories, sewage treatment plant, and public or household facilities. It was found that the most used methodology was unquestionably the monitoring activity, used in 49 of analyzed studies, accounting for 86%. Sometimes, data from historical databases were used as well. It can be seen that taking samples from the water body and then carry on laboratory work (chemical analyses) is important because it can give an understanding of the water quality. 6 papers (11%) used a method that combined monitoring data and modeling. 6 papers (11%) just applied a model to estimate the quality of water. Modeling is a useful resource when there is limited budget since some models are of free download and use. In particular, several of used models come from the U.S.A, but they have their own purposes and features, meaning that a careful application of the models to other countries and a critical discussion of the results are crucial. 5 papers (9%) focus on a method combining monitoring data and statistical analysis. When there is a huge data matrix, the researchers need an efficient way of interpretation of the information which is provided by statistics. 3 papers (5%) used a method combining monitoring data, statistical analysis and modeling. These different methods are all valuable to evaluate the water quality. It was also found that the evaluation of water quality was made as well by using other types of sampling different than water itself, and they also provide useful information to understand the condition of the water body. These additional monitoring activities are: Air sampling, sediment sampling, phytoplankton sampling and aquatic animal tissues sampling. Despite considerable progress in developing and applying control regulations to point and NPS pollution, the pollution status of rivers, lakes, and reservoirs in Asian countries is not improving. In fact, this reflects the slow pace of investment in new infrastructure for pollution control and growing population pressures. Water laws or regulations and public involvement in enforcement can play a constructive and indispensable role in environmental protection. In the near future, in order to protect water from further contamination, rapid action is highly needed to control the various kinds of effluents in one region. Environmental remediation and treatment of industrial effluent and municipal wastewaters is essential. It is also important to prevent the direct input of agricultural and mine site runoff. Finally, stricter environmental regulation for water quality is required to support protection and management strategies. It would have been possible to get further information based in the 57 sample of papers. For instance, it would have been interesting to compare the level of concentrations of some pollutants in the diferente Asian countries. However the limit of three months duration for this study prevented further work to take place. In spite of this, the study objectives were achieved: the work provided an overview of the most relevant water quality problems in rivers, lakes and reservoirs in Asian countries, and also listed and analyzed the most common methodologies.

Pliocene-quaternary upwelling in the SoutheasternAtlantic may reflect changes in water mass production

Proceedings of tile 1" R.C.A.N.S. Congress, Lisboa, October 1992

On the unknown ecological niche of Paracoccidioides brasiliensis: our hypothesis of 1989: present status and perspectives

In 1989, CONTI DÍAZ & RILLA published a hypothesis concerning the as yet unknown ecological niche of Paracoccidioides brasiliensis. The hypothesis proposed a highly efficient paracoccidioidal ecological strategy based on an important natural reservoir of the parasite, probably in heterothermic animals from fresh water environments. Further, the hypothesis proposed, a transient and variable residence in the soil with a wide aleuriospore dispersion throughout the environment together with an elevated capability of infecting humans, and domestic and wild animals. This paper analyzes scientific publications from the IX International Meeting on Paracoccidioidomycosis held in Águas de Lindoia, São Paulo, Brazil from 2-5 October 2005, providing a comparative study among this articles and with other recently published papers and the hypothesis' postulates. Since various findings and observations appear to agree with the postulates, the pursuit of novel, specific research projects in the supposed reservoirs is recommended partially or fully to confirm the hypothesis using classical laboratorial methods and modern molecular biology techniques.

Effects of selection and drift on G matrix evolution in a heterogeneous environment: a multivariate Qst-Fst Test with the freshwater snail Galba truncatula.

Unraveling the effect of selection vs. drift on the evolution of quantitative traits is commonly achieved by one of two methods. Either one contrasts population differentiation estimates for genetic markers and quantitative traits (the Q(st)-F(st) contrast) or multivariate methods are used to study the covariance between sets of traits. In particular, many studies have focused on the genetic variance-covariance matrix (the G matrix). However, both drift and selection can cause changes in G. To understand their joint effects, we recently combined the two methods into a single test (accompanying article by Martin et al.), which we apply here to a network of 16 natural populations of the freshwater snail Galba truncatula. Using this new neutrality test, extended to hierarchical population structures, we studied the multivariate equivalent of the Q(st)-F(st) contrast for several life-history traits of G. truncatula. We found strong evidence of selection acting on multivariate phenotypes. Selection was homogeneous among populations within each habitat and heterogeneous between habitats. We found that the G matrices were relatively stable within each habitat, with proportionality between the among-populations (D) and the within-populations (G) covariance matrices. The effect of habitat heterogeneity is to break this proportionality because of selection for habitat-dependent optima. Individual-based simulations mimicking our empirical system confirmed that these patterns are expected under the selective regime inferred. We show that homogenizing selection can mimic some effect of drift on the G matrix (G and D almost proportional), but that incorporating information from molecular markers (multivariate Q(st)-F(st)) allows disentangling the two effects.

Ecological components and evolution of selfing in the freshwater snail Galba truncatula.

The reproductive assurance hypothesis emphasizes that self-fertilization should evolve in species with reduced dispersal capability, low population size or experiencing recurrent bottlenecks. Our work investigates the ecological components of the habitats colonized by the snail, Galba truncatula, that may influence the evolution of selfing. Galba truncatula is a preferential selfer inhabiting freshwater habitats, which vary with respect to the degree of permanence. We considered with a population genetic approach the spatial and the temporal degree of isolation of populations of G. truncatula. We showed that patches at distances of only a few meters are highly structured. The effective population sizes appear quite low, in the order of 10 individuals or less. This study indicates that individuals of the species G. truncatula are likely to be alone in a site and have a low probability of finding a partner from a nearby site to reproduce. These results emphasize the advantage of selfing in this species.

Paleoparasitological remains revealed by seven historic contexts from "Place d'Armes", Namur, Belgium

Human occupation for several centuries was recorded in the archaeological layers of "Place d'Armes", Namur, Belgium. Preventive archaeological excavations were carried out between 1996/1997 and seven historical strata were observed, from Gallo-Roman period up to Modern Times. Soil samples from cesspools, latrines, and structures-like were studied and revealed intestinal parasite eggs in the different archaeological contexts. Ascaris lumbricoides, A. suum, Trichuris trichiura, T. suis. Taenia sp., Fasciola hepatica, Diphyllobothrium sp., Capillaria sp. and Oxyuris equi eggs were found. Paleoparasitology confirmed the use of structures as latrines or cesspit as firstly supposed by the archaeologists. Medieval latrines were not only used for rejection of human excrements. The finding of Ascaris sp. and Trichuris sp. eggs may point to human's or wild swine's feces. Gallo-Roman people used to eat wild boar. Therefore, both A. suum and T. suis, or A. lumbricoides and T. trichuris, may be present, considering a swine carcass recovered into a cesspit. Careful sediment analysis may reveal its origin, although parasites of domestic animals can be found together with those of human's. Taenia sp. eggs identified in latrine samples indicate ingestion of uncooked beef with cysticercoid larvae. F. hepatica eggs suggest the ingestion of raw contaminated vegetables and Diphyllobothrium sp. eggs indicate contaminated fresh-water fish consumption. Ascaris sp. and Trichuris sp. eggs indicate fecal-oral infection by human and/or animal excrements.

Evolutionary implications of a high selfing rate in the freshwater snail Lymnaea truncatula.

Self-compatible hermaphroditic organisms that mix self-fertilization and outcrossing are of great interest for investigating the evolution of mating systems. We investigate the evolution of selfing in Lymnaea truncatula, a self-compatible hermaphroditic freshwater snail. We first analyze the consequences of selfing in terms of genetic variability within and among populations and then investigate how these consequences along with the species ecology (harshness of the habitat and parasitism) might govern the evolution of selfing. Snails from 13 localities (classified as temporary or permanent depending on their water availability) were sampled in western Switzerland and genotyped for seven microsatellite loci. F(IS) (estimated on adults) and progeny array analyses (on hatchlings) provided similar selfing rate estimates of 80%. Populations presented a low polymorphism and were highly differentiated (F(ST) = 0.58). Although the reproductive assurance hypothesis would predict higher selfing rate in temporary populations, no difference in selfing level was observed between temporary and permanent populations. However, allelic richness and gene diversity declined in temporary habitats, presumably reflecting drift. Infection levels varied but were not simply related to either estimated population selfing rate or to differences in heterozygosity. These findings and the similar selfing rates estimated for hatchlings and adults suggest that within-population inbreeding depression is low in L. truncatula.

Gonadal alterations in male whitefish Coregonus fatioi: no evidence for genetic damage reducing viability in early life stages.

In recent years, numerous cases of morphological gonadal alterations in fish have been recorded throughout the world and across a wide range of species. In the whitefish Coregonus fatioi from the pre-alpine Lake Thun (Switzerland), the frequency of gonadal alterations is particularly high and the variety of alteration types large. Little is known about the proximal causes and the direct consequences of these morphological features on population persistence. In particular, the potential for the observed alterations to be the phenotypic expression of reduced genetic quality has not yet been addressed. In this study, we used offspring survival during embryogenesis as a proximate indicator of male genetic quality and tested whether the presence of gonadal alterations in males is an indicator of reduced quality. Embryos resulted from in vitro fertilizations of gametes from 126 males and females. We found no significant correlation between embryo survival and gonadal alteration in adults. Our findings suggest that in C. fatioi of Lake Thun, alterations in gonad morphology are not a phenotypic expression of variation in genetic quality.

Geometric morphometric analyses provide evidence for the adaptive character of the Tanganyikan cichlid fish radiations.

The cichlids of East Africa are renowned as one of the most spectacular examples of adaptive radiation. They provide a unique opportunity to investigate the relationships between ecology, morphological diversity, and phylogeny in producing such remarkable diversity. Nevertheless, the parameters of the adaptive radiations of these fish have not been satisfactorily quantified yet. Lake Tanganyika possesses all of the major lineages of East African cichlid fish, so by using geometric morphometrics and comparative analyses of ecology and morphology, in an explicitly phylogenetic context, we quantify the role of ecology in driving adaptive speciation. We used geometric morphometric methods to describe the body shape of over 1000 specimens of East African cichlid fish, with a focus on the Lake Tanganyika species assemblage, which is composed of more than 200 endemic species. The main differences in shape concern the length of the whole body and the relative sizes of the head and caudal peduncle. We investigated the influence of phylogeny on similarity of shape using both distance-based and variance partitioning methods, finding that phylogenetic inertia exerts little influence on overall body shape. Therefore, we quantified the relative effect of major ecological traits on shape using phylogenetic generalized least squares and disparity analyses. These analyses conclude that body shape is most strongly predicted by feeding preferences (i.e., trophic niches) and the water depths at which species occur. Furthermore, the morphological disparity within tribes indicates that even though the morphological diversification associated with explosive speciation has happened in only a few tribes of the Tanganyikan assemblage, the potential to evolve diverse morphologies exists in all tribes. Quantitative data support the existence of extensive parallelism in several independent adaptive radiations in Lake Tanganyika. Notably, Tanganyikan mouthbrooders belonging to the C-lineage and the substrate spawning Lamprologini have evolved a multitude of different shapes from elongated and Lamprologus-like hypothetical ancestors. Together, these data demonstrate strong support for the adaptive character of East African cichlid radiations.

Contribution à l'écologie et la zoogéographie de Micropotamogale lamottei (Mammalia, Tenrecidae)

Eighty eight specimens of the West African Pigmy Otter shrew Micropotamogale lamottei were collected in Western Ivory Coast between 1971 and 1976. Most of the animals had been drowned accidentally bow-nets; four were live-trapped by the author. The Pigmy Otter shrew lives not only in swampy areas, as supposed by other authors, but also in small rivers and forest streams. The species is well adapted to its aquatic environment; it feeds mainly on fresh water crab and fish, swims well, is able to remain submerged for 10 to 15 minutes when alarmed, and grooms itself carefully and regularly. A survey carried out locally shows that the species is relatively common in the mountainous region surrounding Danané and Man, and further west in similar habitats of Liberia and Guinea. Its distribution in the Ivory Coast extends no more than 50 km around Danané-Man core-area. It is thought that living Potamogalinae stem from an early adaptative radiation of the Tenrecidae in continental Africa. Later on, the terrestrial forms were probably eliminated by competing Soricidae and Erinaceidae, their aquatic way of life enabling the Potamogalinae to survive until now.

Case studies and mathematical models of ecological speciation. 1. Cichlids in a crater lake.

A recent study of a pair of sympatric species of cichlids in Lake Apoyo in Nicaragua is viewed as providing probably one of the most convincing examples of sympatric speciation to date. Here, we describe and study a stochastic, individual-based, explicit genetic model tailored for this cichlid system. Our results show that relatively rapid (<20,000 generations) colonization of a new ecological niche and (sympatric or parapatric) speciation via local adaptation and divergence in habitat and mating preferences are theoretically plausible if: (i) the number of loci underlying the traits controlling local adaptation, and habitat and mating preferences is small; (ii) the strength of selection for local adaptation is intermediate; (iii) the carrying capacity of the population is intermediate; and (iv) the effects of the loci influencing nonrandom mating are strong. We discuss patterns and timescales of ecological speciation identified by our model, and we highlight important parameters and features that need to be studied empirically to provide information that can be used to improve the biological realism and power of mathematical models of ecological speciation.