Diving behaviour of two Australian bimodally respiring turtles, Rheodytes leukops and Emydura macquarii, in a natural setting

Time-depth recorders were used to investigate the diving performance and behaviour of two bimodally respiring turtle species, Rheodytes leukops and Emydura niacquarii, known to have a high and low reliance on aquatic respiration, respectively. Significant differences in diving performance between R. leukops and E. macquarii were observed in the number of dives/day (39.3 +/- 5.38 vs 112.2 +/- 11.73 dives/day; mean +/- SE), mean dive length (33.1 +/- 7.33 min vs 9.6 +/- 2.26 min) and maximum dive length (623 +/- 104.74 min vs 67.1 +/- 8.14 min), respectively. Differences in diving performance between R. leukops and E macquarii are attributed to the species' reliance (or lack thereof) upon aquatic respiration. Rheodytes leukops displayed a weak bimodal pattern of increased surfacing frequency in the early morning (05:00-07:00) and late afternoon (14:00-18:00), while E. macquarii displayed a strong bimodal pattern of elevated surfacing frequency over similar time periods. Daily patterns of increased surfacing frequency for both species failed to correlate with fluctuating aquatic Po-2 levels or water temperature, and may instead be explained by the heightened activity levels of both species during twilight.

Effect of water temperature and oxygen levels on the diving behavior of two freshwater turtles: Rheodytes leukops and Emydura macquarii

Rheodytes leukops is a bimodally respiring turtle that extracts oxygen from the water chiefly via two enlarged cloacal bursae that are lined with multi-branching papillae. The diving performance of R. leukops was compared to that of Emydura macquarii, a turtle with a limited ability to acquire aquatic oxygen. The diving performance of the turtles was compared under aquatic anoxia (0 mmHg), hypoxia (80 mmHg) and normoxia (155 mmHg) at 15, 23, and 30degreesC. When averaged across all temperatures the dive duration of R. leukops more than doubled from 22.4 +/- 7.65 min under anoxia to 49.8 +/- 19.29 min under normoxic conditions. In contrast, aquatic oxygen level had no effect on the dive duration of E. macquarii. Dive times for both species were significantly longer at the cooler temperature, and the longest dive recorded for each species was 538 min and 166 min for R. leukops and E. macquarii, respectively. Both species displayed a pattern of many short dives punctuated by occasional long dives irrespective of temperature or oxygen regime. Rheodytes leukops, on average, spent significantly less time (42 +/- 2 sec) at the surface per surfacing event than did E. macquarii (106 +/- 20 sec); however, surface times for both species were not related to either water temperature or oxygen level.

pido, a non-long terminal repeat retrotransposon of the chicken repeat 1 family from the genome of the Oriental blood fluke, Schistosoma japonicum

A newly described non-long terminal repeat (non-LTR) retrotransposon element was isolated from the genome of the Oriental schistosome, Schistosoma japonicum. At least 1000 partial copies of the element, which was named pido, were dispersed throughout the genome of S. japonicum. As is usual with non-LTR retrotransposons, it is expected that many pido elements will be 5'-truncated. A consensus sequence of 3564 bp of the truncated pido element was assembled from several genomic fragments that contained pido-hybridizing sequences. The sequence encoded part of the first open reading frame (ORF), the entire second ORF and, at its 3'-terminus, a tandemly repetitive, A-rich (TA(6)TA(5)TA(8)) tail, The ORF1 of pido encoded a nucleic acid binding protein and ORF2 encoded a retroviral-like polyprotein that included apurinic/apyrimidinic endonuclease (EN) and reverse transcriptase (RT) domains, in that order. Based on its sequence and structure, and phylogenetic analyses of both the RT and EN domains, pido belongs to the chicken repeat 1 (CR1)-like lineage of elements known from the chicken, turtle, puffer fish, mosquitoes and other taxa. pido shared equal similarity with CRI from chicken, an uncharacterized retrotransposon from Caenorhabditis elegans and SR1 (a non-LTR retrotransposon) from the related blood fluke Schistosoma mansoni; the level of similarity between pido and SR1 indicated that these two schistosome retrotransposons were related but not orthologous. The findings indicate that schistosomes have been colonized by at least two discrete CRI-like elements. Whereas pido did not appear to have a tight target site specificity, at least one copy of pido has inserted into the 3'-untranslated region of a protein-encoding gene (GeriBank AW736757) of as yet unknown identity. mRNA encoding the RT of pido was detected by reverse transcription-polymerase chain reaction in the egg, miracidium. and adult developmental stages of S. japonicum, indicating that the RT domain was transcribed and suggesting that pido was replicating actively and mobile within the S. japonicum genome. (C) 2002 Elsevier Science B.V. All rights reserved.

Etiology of ovarian failure in blepharophimosis ptosis epicanthus inversus syndrome: FOXL2 is a conserved, early-acting gene in vertebrate ovarian development

Blepharophimosis ptosis epicanthus inversus syndrome (BPES) is a human disorder caused by mutations in the forkhead transcription factor gene FOXL2 and is characterized by facial dysmorphology combined in some cases with ovarian failure. To better understand the role of FOXL2 in the etiology of ovarian failure in BPES, we examined its expression in embryonic ovaries of mice, chickens, and red-eared slider turtles, representatives of three phylogenetically distant vertebrate groups that have different mechanisms of sex determination. Expression of Foxl2 was detected in early ovaries of all three species around the time of sex determination and was associated with both somatic and germ cell populations in mice. Expression was sexually dimorphic in all cases. Sequence analysis of turtle and chicken FoxL2 orthologues indicated an unusually high degree of structural conservation during evolution. FoxL2 was found to be autosomal in chickens, and therefore unlikely to represent the dominant ovarian-determining gene that has been postulated to exist as a possible explanation for female heterogamety in birds. Our observations suggest that BPES may result from early abnormalities in regulating the development of the fetal ovary, rather than premature degeneration of the postnatal or adult ovary. Further, our results suggest that FOXL2 is a highly conserved early regulator of vertebrate ovarian development.

Variação na dieta da tartaruga verde, Chelonia mydas, e o impacto da ingestão de lixo ao longo da costa brasileira

Neste trabalho nós estudamos a dieta da tartaruga verde, Chelonia mydas, e os fatores envolvidos na variação de sua ecologia alimentar. Avaliamos também o impacto da ingestão de lixo, e os fatores que podem explicar a elevada ingestão destes resíduos entre os animais marinhos. No estudo da ecologia alimentar, nós avaliamos mais de 400 indivíduos, entre dados originais e da literatura, distribuídos ao longo de um gradiente latitudinal e diversos ambientes. As tartarugas se alimentaram majoritariamente de macroalgas, porém apresentaram uma grande plasticidade alimentar, tanto em relação à estratégia de forrageamento quanto à dieta. Nas regiões mais frias e com menor disponibilidade de algas, as tartarugas mudaram de uma dieta herbívora, para uma dieta baseada em matéria animal. Esta mudança de dieta acarretou também em uma mudança de estratégia de forrageamento, saindo da alimentação bentônica para uma alimentação pelágica. Estratégia esta que também foi encontrada nas áreas estuarinas. A plasticidade alimentar se deve à interação de fatores intrínsecos (restrições fisiológicas) e extrínsecos (regionais e locais). As diferenças nas estratégias de forragenamento acarretam também em diferenças na exposição a ameaças. Um exemplo disso é a ingestão de lixo, que apesar de ter sido registrada em mais de 70% das tartarugas (N = 265), representou uma ameaça maior aos animais com estratégia de forrageamento pelágica. O plástico foi o material mais ingerido, tendo como principal fonte itens relacionados à alimentação e sacolas plásticas. O estudo também mostrou que uma quantidade pequena de lixo (0,5 g) é suficiente para causar a morte. Este resultado revelou que o potencial de letalidade por ingestão de lixo é muito maior que a mortalidade observada. A verdadeira ameaça da ingestão de lixo está sendo mascarada pela elevada mortalidade relacionada às atividades pesqueiras. A ingestão de lixo é normalmente atribuída à confusão de um item alimentar específico com o resíduo, como águas-vivas e sacolas plásticas. Porém, nós mostramos que se trata de uma questão mais ampla, e usamos a tartaruga verde, aves marinhas e peixes para ressaltar a importância de outros fatores como: abundância do lixo no ambiente, estratégia de forrageamento, capacidade de detecção do resíduo e amplitude da dieta. Nós acreditamos que a ingestão de lixo ocorre devido a uma armadilha evolutiva muito mais ampla do que a previamente sugerida, e que deve afetar muito mais espécies que as que foram até hoje reportadas. Desarmar esta armadilha será particularmente difícil devido ao contínuo e crescente despejo de plástico no ambiente marinho e sua alta persistência no ambiente.

Neochelys sp. (Chelonii, Erymnochelyinae), from Silveirinha, early Eocene, Portugal

Constituted of isolated fragments with a smooth decoration, the turtle material from Silveirinha is examined in order to define its sure belonging to Neochelys, by comparison with other smooth turtles which may be present during the Palaeogene of Europe (freshwater Testudinidae, Erymnochelyinae, Bothremydidae). The elements are compared with the already known Neochelys species of the Eocene European localities. Questions are made about the possible geographical migrations of turtles between South and North during the early Eocene of western Europe. The phyletic relationships cannot be established but the species, seeming new and one of the more primitive as a whole (after the preserved elements), is the older from the Iberian Peninsula.

Energy Harvesting for Autonomous Underwater Vehicles

In this study, energy production for autonomous underwater vehicles is investigated. This project is part of a bigger project called TURTLE. The autonomous vehicles perform oceanic researches at seabed for which they are intended to be kept operational underwater for several months. In order to ful l a long-term underwater condition, powerful batteries are combined with \micro- scale" energy production on the spot. This work tends to develop a system that generates power up to a maximum of 30 W. Latter energy harvesting structure consists basically of a turbine combined with a generator and low-power electronics to adjust the achieved voltage to a required battery charger voltage. Every component is examined separately hence an optimum can be de ned for all, and subsequently also an overall optimum. Di erent design parameters as e.g. number of blades, solidity ratio and cross-section area are compared for di erent turbines, in order to see what is the most feasible type. Further, a generator is chosen by studying how ux distributions might be adjusted to low velocities, and how cogging torque can be excluded by adapted designs. Low-power electronics are con gured in order to convert and stabilize heavily varying three-phase voltages to a constant, recti ed voltage which is usable for battery storage. Clearly, di erent component parameters as maximum power and torque are matched here to increase the overall power generation. Furthermore an overall maximum power is set up for achieving a maximum power ow at load side. Due to among others typical low velocities of about 0.1 to 0.5 m/s, and constructing limits of the prototype, the vast range of components is restricted to only a few that could be used. Hence, a helical turbine is combined in a direct drive mode to a coreless-stator axial- ux permanent-magnet generator, from which the output voltage is adjusted subsequently by a recti er, impedance matching unit, upconverter circuit and an overall control unit to regulate di erent component parameters. All these electronics are combined in a closed-loop design to involve positive feedback signals. Furthermore a theoretical con guration for the TURTLE vehicle is described in this work and a solution is proposed that might be implemented, for which several design tests are performable in a future study.

Geological control of Podocnemis expansa and Podocnemis unifilis nesting areas in Rio Javaés, Bananal Island, Brazil

The distribution of the nests of Podocnemis expansa (Amazon turtle) and Podocnemis unifilis (yellow-spotted side neck turtle) along the point bars of the Javaés River in Bananal Island, demonstrates a clear preference of these chelonians for differentiated geological environments, in respect to the morphology, grain size or height of the nests in relation to the level of the river. The topographical distribution and the differences in the grain size of the sediments that compose the point bars of the river, originated from the multiple sedimentary processes, and make possible the creation and separation of different nesting environments. Each turtle species takes advantage of the place that presents physiographic characteristics appropriate to the hatching success of their eggs. The superposition of the P. expansa and P. unifilis nest placement areas is rare. The P. expansa nests are concentrated on the central portion of the beaches where successive depositional sedimentary events produced sandy banks more than 3.3 m above the river water level. The P. unifilis nests are distributed preferentially in the upstream and downstream portions along the point bars where the sandy deposits rarely surpass 1.5 m at the moment of laying. P. expansa nests located on the beaches of fine to medium sized sand hatch in a mean of 68 days, while those incubated on beaches of medium to coarse sand size take a mean of 54 days to hatch.

Ontogenetic variation of plastral spotting pattern in Phrynops hilarii (Testudines, Chelidae)

The plastral spotting variation in the chelid turtle Phrynops hilarii (Duméril & Bibron, 1835) in relation to sex, size, and geographic procedence of individuals was analyzed. States for qualitative characters were analyzed using non-parametric tests. Quantitative characters (shell and scute measurements) were standardized for body size by linear regression against carapace length, and were subjected to principal components analysis and canonical discriminant function analysis. Results suggest that increased plastral spotting is a polymorphic ontogenetic trait in P. hilarii. Neither hatchlings nor juveniles have plastral pattern moderately or heavily pigmented. The simplest pattern, however, may persist without changes in some adults. There are no differences between sexes. The spatial distribution of the plastral pattern is not ordered latitudinally or longitudinally, showing no relationship with gradients of elevation, temperature, or precipitation. This pattern trait lacks of taxonomic significance. The morphometric analysis failed to reveal any character of diagnostic utility in the plastron to support the possibility that these patterns correspond to different sympatric taxa.

Ecological conflicts and valuation - mangroves vs. shrimp in the late 1990s

Shrimps are produced in two different ways. They are fished in the sea (sometimes at the cost of turtle destruction) or they are "farmed" in ponds in coastal areas. Such aquaculture is increasing around the world as shrimps become a valuable item of world trade. Mangrove forests are sacrificed for commercial shrimp farming. This paper considers the conflict between mangrove conservation and shrimp exports in different countries.Who has title to the mangroves, who wins and who loses in this tragedy of enclosures? Which languages of valuation are used by different actors in order to compare the increase in shrimp exports and the losses in livelihoods and in environmental services? The economic valuation of damages is only one of the possible languages of valuation which are relevant in practice. Who has the power to impose a particular language of valuation?

Eimeria species (Apicomplexa: Eimeriidae) of podocnemis expansa (Schweigger) and geochelone denticulata (LINN.) from Amazonian Brazil (Reptilia: Chelonia)

Eimeria lagunculata, Eimeria mammiformis and Eimeria podocnemis n. spp., are described from the faeces of the fresh-water turtle Podocnemis expansa, in Pará State, north Brasil. Oocysts of E. lagunculata are ellipsoidal, 19.2 x 12.8 (17.0-20.7 x 11.8-14.1) mum, shape-index (= length/ width) 1.5 (1.4-1.7). Oocyst wall about 0.5-0.7 mum thick, with a prominent stopper-like micropyle at one pole. No oocyst residuum and no polar body. Sporocysts elongate ellipsoidal, 11.0 x 5.4 (10.4-11.8 x 5.2-6.0) mum, shape-index 2.0 (1.8-2.1): no Stieda body. A compact, ellipsoidal sporocyst residuum lies between the two sporozoites, which possess a posterior and an anterior refractile body. Oocysts of E. mammiformis broadly ellipsoidal, 30.0 x 19.4 (23.0-37.0 x 16.3-21.5) mum, shape-index 1.5 (1.1-1.9). Oocyst wall about 0.7 mum thick, with a prominent micropyle: no oocyst residuum and rarely a single polar body. Sporocysts ellipsoidal, 15.3 x 7.9 (14.8-17.0 x 7.4-9.6) mum, shape-index 2.0 (1.8-2.2), with a tiny Stieda body. Sporocyst residuum bulky, ellipsoidal: sporozoites with two conspicuous refractile bodies. E. podocnemis has broadly ellipsoidal oocysts, 17.0 x 12.8 (14.8-19.2 x 11.8-14.1) mum, shape-index 1.3 (1.1-1.4). Oocyst wall about 0.5-0.7 mum thick, with no micropyle. No oocyst residuum, but always a single polar body. Sporocysts ellipsoidal, 9.7 x 5.2 (8.9-10.4 x 4.4-6.0) mum, shape-index 1.9 (1.6-2.0), with no Stieda body. Sporocyst residuum bulky, ellipsoidal: sporocysts with 2 refractile bodies. Eimeria carinii n. sp., is recorded from the tortoise Geochelone denticulata, also from Pará. Oocyst wall about 1.2 mum thicl. No micropyle. Oocyst residuum limited to a number (about 10-20) of scattered granules: no polar body. Sporocysts broadly ellipsoidal, and with no Stieda body: they measure 8,8 x 7.3 (8.0-9.0 x 7.0-7.5) mum, shape-index 1.2 (1.1-1.3). Sporocyst residuum bulky, spherical to ellipsoidal: sporozoites possess both posterior and anterior refractile bodies.

Three-dimensional slope stability analysis of South Peak, Crowsnest Pass, Alberta, Canada

South Peak is a 7-Mm3 potentially unstable rock mass located adjacent to the 1903 Frank Slide on Turtle Mountain, Alberta. This paper presents three-dimensional numerical rock slope stability models and compares them with a previous conceptual slope instability model based on discontinuity surfaces identified using an airborne LiDAR digital elevation model (DEM). Rock mass conditions at South Peak are described using the Geological Strength Index and point load tests, whilst the mean discontinuity set orientations and characteristics are based on approximately 500 field measurements. A kinematic analysis was first conducted to evaluate probable simple discontinuity-controlled failure modes. The potential for wedge failure was further assessed by considering the orientation of wedge intersections over the airborne LiDAR DEM and through a limit equilibrium combination analysis. Block theory was used to evaluate the finiteness and removability of blocks in the rock mass. Finally, the complex interaction between discontinuity sets and the topography within South Peak was investigated through three-dimensional distinct element models using the code 3DEC. The influence of individual discontinuity sets, scale effects, friction angle and the persistence along the discontinuity surfaces on the slope stability conditions were all investigated using this code.

La llengua de l'enemic com a llengua pròpia: cultures translatives del paisatge indígena nord-americà

This research paper seeks to bring into view the present-day situation of Native-American narrative in English. It is divided into four chapters. The first deals with the emergence of what we might call a Native-American narrative style and its evolution from 1900 up until its particularly forceful expression in 1968 with the appearance of N. Scott Momaday’s novel House Made of Dawn. To trace this evolution, we follow the chronology set forth by Paula Gunn Allen in her anthology Voice of the Turtle: American Indian Literature 1900-1970. In the second chapter we hear various voices from contemporary Native-American literary production as we follow Simon J. Ortiz’s anthology Speaking for the Generations: Native Writers on Writing. Noteworthy among these are Leslie Marmon Silko and Gloria Bird, alongside new voices such as those of Esther G. Belin and Daniel David Moses, and closing with Guatemalan-Mayan Victor D. Montejo, exiled in the United States. These writers’ contributions gravitate around two fundamental notions: the interdependence between human beings and the surrounding landscape, and the struggle for survival, which of necessity involves the deconstruction of the (post-)colonial subject. The third chapter deals with an anthology of short stories and poems by present-day Native-American women writers, edited by Joy Harjo and Gloria Bird and entitled Reinventing the Enemy’s Language: Contemporary Native Women’s Writings of North America. It too exemplifies personal and cultural reaffirmation on a landscape rich in ancestral elements, but also where one’s own voice takes shape in the language which, historically, is that of the enemy. In the final chapter we see how translation studies provide a critical perspective and fruitful reflection on the literary production of Native-American translative cultures, where a wide range of writers struggle to bring about the affirmative deconstruction of the colonialised subject. Thus there comes a turnaround in the function of the “enemy’s language,” giving rise also to the question of cultural incommensurability.

First report of Temnocephala brevicornis Monticelli 1889 (Temnocephalidae: Platyhelminthes) in Argentina

Temnocephala brevicornis Monticelli 1889, ectosymbiont of Hydromedusa tectifera Cope 1869, is reported for the first time for Argentina. Numerous temnocephalans from Arroyo Villoldo in the locality of Magdalena, Buenos Aires, Argentina were stained in toto to be studied. This commensal species in turtles was originally cited in association with Hydromedusa maximiliani (Mikan) and Hydraspis radiolata Mikan in Brazil. Afterwards, it was found on other fresh water turtle species in Brazil and Uruguay.

Neopolystoma fentoni n. sp. (Monogenea: Polystomatidae) a parasite of the conjunctival sac of freshwater turtles in Costa Rica

Neopolystoma fentoni n. sp. is described from the conjunctival sac of Kinosternon leucostomum (Duméril, Bibron, and Duméril 1851) and Rhinoclemmys pulcherrima (Gray 1855) from the Guanacaste Conservation Area in Costa Rica. The new species differs from all other species of Neopolystoma, except N. elizabethae Platt 2000 in possessing a circle of eight genital spines that are recurved and possess a crescent-shaped base. N. fentoni n. sp. differs from N. elizabethae in lacking cecal diverticula and in a number of morphometric criteria.