118 A Nutritional Analysis of the Turf Algal Diet and Fecal Pellets of The Green Turtle,Chelonia Mydas L

In 1978, the green turtle, Chelonia mydas, was listed as threatened in the United States under the Endangered Species Act. Any knowledge gained from an understanding of the diet and how it affects this species' ability to survive is crucial. Turf algae, the primary component of the diet of Chelonia mydas, and turtle fecal pellets were collected from Kaloko‐Honokohau National Historical Park on the island of Hawaii at monthly intervals. The turf algae and fecal pellets were subjected to nutritional analyses for protein, carbohydrate, lipid, ash, and caloric content. The fecal pellets were higher in protein content than the turf algae, which may be related to fermentation carried out by bacteria in the turtle hindgut that increases the amount of protein available for absorption. From the nutritional data, assimilation efficiencies were calculated for the green turtle.     

Global Population Genetic Structure and Male-Mediated Gene Flow in the Green Turtle (Chelonia Mydas): RFLP Analyses of Anonymous Nuclear Loci

We introduce an approach for the analysis of Mendelian polymorphisms in nuclear DNA (nDNA), using restriction fragment patterns from anonymous single-copy regions amplified by the polymerase chain reaction, and apply this method to the elucidation of population structure and gene flow in the endangered green turtle, Chelonia mydas. Seven anonymous clones isolated from a total cell DNA library were sequenced to generate primers for the amplification of nDNA fragments. Nine individuals were screened for restriction site polymorphisms at these seven loci, using 40 endonucleases. Two loci were monomorphic, while the remainder exhibited a total of nine polymorphic restriction sites and three size variants (reflecting 600-base pair (bp) and 20-bp deletions and a 20-bp insertion). A total of 256 turtle specimens from 15 nesting populations worldwide were then scored for these polymorphisms. Genotypic proportions within populations were in accord with Hardy-Weinberg expectations. Strong linkage disequilibrium observed among polymorphic sites within loci enabled multisite haplotype assignments. Estimates of the standardized variance in haplotype frequency among global collections (FST = 0.17), within the Atlantic-Mediterranean (FST = 0.13), and within the Indian-Pacific (FST = 0.13), revealed a moderate degree of population substructure. Although a previous study concluded that nesting populations appear to be highly structured with respect to female (mitochondrial DNA) lineages, estimates of Nm based on nDNA data from this study indicate moderate rates of male-mediated gene flow. A positive relationship between genetic similarity and geographic proximity suggests historical connections and/or contemporary gene flow between particular rookery populations, likely via matings on overlapping feeding grounds, migration corridors or nonnatal rookeries.     

Blood Gases,Biochemistry, and Hematology of Galapagos Green Turtles (Chelonia Mydas)

The green turtle, Chelonia mydas, is an endangered marine chelonian with a circum-global distribution. Reference blood parameter intervals have been published for some chelonian species, but baseline hematology, biochemical, and blood gas values are lacking from the Galapagos sea turtles. Analyses were done on blood samples drawn from 28 green turtles captured in two foraging locations on San Cristóbal Island (14 from each site). Of these turtles, 20 were immature and of unknown sex; the other eight were males (five mature, three immature). A portable blood analyzer (iSTAT) was used to obtain near immediate field results for pH, lactate, pO₂, pCO₂, HCO₃⁻, Hct, Hb, Na, K, iCa, and Glu. Parameter values affected by temperature were corrected in two ways: (1) with standard formulas; and (2) with auto-corrections made by the iSTAT. The two methods yielded clinically equivalent results. Standard laboratory hematology techniques were employed for the red and white blood cell counts and the hematocrit determination, which was also compared to the hematocrit values generated by the iSTAT. Of all blood analytes, only lactate concentrations were positively correlated with body size. All other values showed no significant difference between the two sample locations nor were they correlated with body size or internal temperature. For hematocrit count, the iSTAT blood analyzer yielded results indistinguishable from those obtained with high-speed centrifugation. The values reported in this study provide baseline data that may be useful in comparisons among populations and in detecting changes in health status among Galapagos sea turtles. The findings might also be helpful in future efforts to demonstrate associations between specific biochemical parameters and disease.     

Conservation Genetics of the East Pacific Green Turtle (Chelonia mydas) in Michoacan, Mexico

The main continental nesting rookeries of the east Pacific green turtle (EPGT), Chelonia mydas, on the Michoacan (Mexico) coast suffered drastic population declines following intense exploitation in the 1960s--1970s with annual abundance of nesting females plummeting from about 25,000 to an average of about 1400 between 1982 and 2001. Analyses of data from three nDNA microsatellite loci and 400 bp mtDNA control region sequences from a total of 123 nesting females sampled from four Michoacan rookeries found no evidence of population sub-structuring. The recent order of magnitude reduction in the population size shows no apparent impact on genetic diversity in either control region sequences (overall h = 0.48; pi = 0.0036) or microsatellite loci (overall Na = 20.8; Hexp = 0.895). Our estimates of annual effective female population size (Nef; from theta = 2Nemicron) of 1.9-2.3 x 10(3), in spite of being an order of magnitude below historical records, appear to be sufficient to allow recovery of this population without significant loss of genetic diversity. These findings highlight the importance of continued conservation to reverse the decline of this population before it becomes vulnerable to genetic erosion.     

Amino Acid Sequence and Activity of Green Turtle (Chelonia mydas) Lysozyme

Green turtle lysozyme purified from egg white was sequenced and analyzed its activity. Lysozyme was reduced and pyridylethylated or carboxymethylated to digest with trypsin, chymotrypsin and V8 protease. The peptides yielded were purified by RP-HPLC and sequenced. Every trypsin peptide was overlapped by chymotrypsin peptides and V8 protease peptides. This lysozyme is composed of 130 amino acids including an insertion of a Gly residue between 47 and 48 residues when compared with chicken lysozyme. The amino acid substitutions were found at subsites E and F. Namely Phe34, Arg45, Thr47, and Arg114 were replaced by Tyr, Tyr, Pro, and Asn, respectively. The time course using N-acetylglucosamine pentamer as a substrate showed a reduction of the rate constant of glycosidic cleavage and transglycosylation and increase of binding free energy for subsite E, which proved the contribution of amino acids mentioned above for substrate binding at subsites E and F.     

Structure and Function of the Gastrointestinal Tract of the Green Turtle(Chelonia mydas) Hatchling

The gastrointestinal tracts of four Chelonia mydas hatchlings were examined at the anatomical, histological and ultrastructural level. Our results show that the gastrointestinal tract(GI) is composed by esophagus, stomach, small intestine(SI) and large intestine(LI), and histologically of mucosa, submucosa, muscularis externa(ME) and serosa. The esophagus is marked by conical papillae lined by keratinized stratified squamous epithelium, whereas the remaining GI by simple columnar epithelium; esophageal diverticulum is absent. The stomach covered with mucous granule cells, contains cardia, fundic regions and pylorus, which are separately characterized by cardiac glands, fundic glands and pyloric glands, and have the thickest submucosa and ME of the GI. The ME of the esophagus mainly consist of one layer of circular smooth muscle whereas the rest of GI of two layers, inner circular muscle and outer longitudinal muscle. The SI is slightly longer than the LI and the GI is approximately 5.11 times of the carapace length. The SI is lined with longitudinal zigzag folds and characterized by absorptive cells with longer and denser microvilli, whereas the LI by transversal folds, goblet cells and lymphoid nodules. Only intestinal glands appear in duodenum. Endocrine cells are observed in all sections of the GI and accounted for the largest proportion in duodenum. The results demonstrate a perfect combination of the structure and function of the GI and reveal that the digestion and absorption primarily occurs in the foregut. C. mydas hatchling may prefer carnivorous diet.     

The feminizing effect of metabolic heating in Green Turtle (Chelonia mydas) clutches in the eastern Mediterranean

Metabolic heating has been poorly investigated in eastern Mediterranean coastline of Turkey, which host some of the most important Green Turtle (Chelonia mydas) nesting sites in the Mediterranean. We studied the effects of clutch size and embryo numbers on nest temperature and discuss the feminizing effect of metabolic heating. Two test sites were conducted in Sugözü Beaches (Turkey). Data loggers were placed in eight nests with different clutch sizes. Nest temperature was strongly correlated with embryo numbers and metabolic heating produced by embryos was calculated to be 0.019°C per late stage embryo and 0.020°C per hatchling. Metabolic heating was calculated to be 0.6°C in the middle third of the incubation period during which sex is determined. It was estimated that metabolic heating increased 10.4% of female hatchlings. The heat produced by embryos should be taken into consideration while estimating sex ratios indirectly by nest and sand temperatures. Additionally, the metabolic heating value should be known for conservation measures, such as nest relocation, dividing the nest for controlling nest temperature, especially related to climate change.     

The Complete Amino Acid Sequence of Green Turtle (Chelonia mydas) Egg White Ribonuclease

Egg white ribonuclease was first found in green turtle eggs. This enzyme has been purified by CM-toyopearl cation exchange. Two isoforms (GTRNase-1 and GTRNase-2) were further separated by RP-HPLC, with the same M.W. (13 kDa) and activity. These isoforms carried one amino acid exchange of Ser and Leu at the position 37. The N-terminal sequence, ETRYEKF, was determined for the transblotted protein. Internal sequences were analyzed by protein sequencer and ESI-Q-TOF mass spectrometry for tryptic peptides (Ts). The overlapping sequences were obtained from chymotryptic peptides, CNBr fragments and ISD-MS/MS analysis. The C-terminal Ile was identified by CPase-Y. The established sequence composed of 119 residues with the molecular mass of 12,942.1 Da for GTRNase-1 and 12,967.8 Da for GTRNase-2. The comparison of sequence with known pancreatic RNases, 27 positions including catalytic residues at the position 11 and 114 were conserved. Also basic residues contributed to phosphate binding residues were conserved with the exception of Lys 66. One insertion at the position 14, and 3 deletions at the position-1, between position 64–65, and 110 and 111 were found. Two Cys residues at position 65 and 72 that form a disulfide bond in mammalian RNase were deleted and exchanged. All these difference in the sequence were similar to reptile pancreatic RNase.Data deposition: The sequence reported in this paper has been submitted to the UniProt Knowledgebase under accession No. P84844.     

Dispersal and Diving Adjustments of the Green Turtle Chelonia mydas in Response to Dynamic Environmental Conditions during Post-Nesting Migration

In response to seasonality and spatial segregation of resources, sea turtles undertake long journeys between their nesting sites and foraging grounds. While satellite tracking has made it possible to outline their migration routes, we still have little knowledge of how they select their foraging grounds and adapt their migration to dynamic environmental conditions. Here, we analyzed the trajectories and diving behavior of 19 adult green turtles (Chelonia mydas) during their post-nesting migration from French Guiana and Suriname to their foraging grounds off the coast of Brazil. First Passage Time analysis was used to identify foraging areas located off Ceará state of Brazil, where the associated habitat corresponds to favorable conditions for seagrass growth, i.e. clear and shallow waters. The dispersal and diving patterns of the turtles revealed several behavioral adaptations to the strong hydrodynamic processes induced by both the North Brazil current and the Amazon River plume. All green turtles migrated south-eastward after the nesting season, confirming that they coped with the strong counter North Brazil current by using a tight corridor close to the shore. The time spent within the Amazon plume also altered the location of their feeding habitats as the longer individuals stayed within the plume, the sooner they initiated foraging. The green turtles performed deeper and shorter dives while crossing the mouth of the Amazon, a strategy which would help turtles avoid the most turbulent upper surface layers of the plume. These adjustments reveal the remarkable plasticity of this green turtle population when reducing energy costs induced by migration.     

Evolutionary Origin of the Turtle Shell

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Nesting Phenology of Marine Turtles: Insights from a Regional Comparative Analysis on Green Turtle (Chelonia mydas)

Changes in phenology, the timing of seasonal activities, are among the most frequently observed responses to environmental disturbances and in marine species are known to occur in response to climate changes that directly affects ocean temperature, biogeochemical composition and sea level. We examined nesting seasonality data from long-term studies at 8 green turtle (Chelonia mydas) rookeries that include 21 specific nesting sites in the South-West Indian Ocean (SWIO). We demonstrated that temperature drives patterns of nesting seasonality at the regional scale. We found a significant correlation between mean annual Sea Surface Temperature (SST) and dates of peak nesting with rookeries exposed to higher SST having a delayed nesting peak. This supports the hypothesis that temperature is the main factor determining peak nesting dates. We also demonstrated a spatial synchrony in nesting activity amongst multiple rookeries in the northern part of the SWIO (Aldabra, Glorieuses, Mohéli, Mayotte) but not with the eastern and southern rookeries (Europa, Tromelin), differences which could be attributed to females with sharply different adult foraging conditions. However, we did not detect a temporal trend in the nesting peak date over the study period or an inter-annual relation between nesting peak date and SST. The findings of our study provide a better understanding of the processes that drive marine species phenology. The findings will also help to predict their ability to cope with climate change and other environmental perturbations. Despite demonstrating this spatial shift in nesting phenology, no trend in the alteration of nesting dates over more than 20 years was found.     

Evolutionary Aspects of Functional and Pseudogene Members of the Phytochrome Gene Family in Scots Pine

According to the neutral theory of evolution, mutation and genetic drift are the only forces that shape unconstrained, neutral, gene evolution. Thus, pseudogenes (which often evolve neutrally) provide opportunities to obtain direct estimates of mutation rates that are not biased by selection, and gene families comprising functional and pseudogene members provide useful material for both estimating neutral mutation rates and identifying sites that appear to be under positive or negative selection pressures. Conifers could be very useful for such analyses since they have large and complex genomes. There is evidence that pseudogenes make significant contributions to the size and complexity of gene families in pines, although few studies have examined the composition and evolution of gene families in conifers. In this work, I examine the complexity and rates of mutation of the phytochrome gene family in Pinus sylvestris and show that it includes not only functional genes but also pseudogenes. As expected, the functional PHYO does not appear to have evolved neutrally, while phytochrome pseudogenes show signs of unconstrained evolution.     

Symbiotic Cellulose Degradation in Green Turtles, Chelonia mydas L

A postgastric, fermentative breakdown of structural plant tissue was demonstrated for green turtles. About 90% cellulose was hydrolyzed. Bacterial and protozoan numbers compared with those of the rumen.     

The Development and Evolution of the Turtle Body Plan: Inferring Intrinsic Aspects of the Evolutionary Process from Experimental Embryology

The body plan of turtles is unique among tetrapods in the presenceof the shell. The structure of the carapace involves a uniquerelationship between the axial and the appendicular skeletons.A common developmental mechanism, an epithelial-mesenchymalinteraction, has been identified in the early stages of carapacedevelopment by means of basic histological and immunofluorescencetechniques. By analogy to other structures initiated by epithelial-mesenchymalinteractions, it is hypothesized that carapace development isdependent on this interaction in the body wall. Surgical perturbationswere designed to test the causal connection between the epithelial-mesenchymalinteraction in the body wall and the unusual placement of theribs in turtles. By comparison to data available on body wallformation in avian embryos, these experiments also shed lighton the segregation of somitic and lateral plate cell populationsand the embryonic origin of the scapula in turtles. This study specifically addresses the ontogeny of a unique tetrapodbody plan. The ontogenetic information can be used to make inferencesabout the phytogeny of this body plan and how it could haveevolved from the more typical primitive tetrapod. On a moregeneral level this studyexplores the potential role of commondevelopmental mechanisms in the generation of evolutionary novelties,and the developmental incongruities between homologous skeletalelements in different groups of tetrapods.     

The stomach content of a Mediterranean Monk Seal (Monachus monachus): finding of Green Turtle (Chelonia mydas) remains

The stomach contents of an adult Mediterranean Monk Seal (Monachus monachus) found stranded on the Turkish eastern Mediterranean coast near Antalya in May 2013 were analysed. In total, 69 individual food items were counted and nine taxa were identified to species or family level. Of the identified taxa, Sparidae was the most highly represented family of prey fish, and one cephalopod species, Octopus vulgaris, was found. Ariosoma balearicum and Argyrosomus regius were encountered for the first time in the diet of a Monk Seal in the Mediterranean. Several body parts (three heads, six forelimbs, neck bones and fractured upper forelimb bones) of Green Turtles (Chelonia mydas) were also identified, which is the first record of this species in the Monk Seal’s diet.     

Developmental and Evolutionary Aspects of the Neurohypophysis

Although phylogenetic studies of neurohypophysial principlesare well advanced, studies of their development are rare. Fetalmammals have been shown to have unusually high vasopressor/oxytocicratios in their pituitaries. Paper chromatography of extractsfrom pituitaries of fetal sheep and fetal seals (Callorhinusursinus) indicated the presence of AVT, in addition to AVP andoxytocin. This was confirmed by the pharmacological and chemicalanalysis of AVT, purified from fetal seal pituitaries. The presenceof AVT suggested a "recapitulation" of a principle previouslyknown only in sub-mammalian vertebrates. Studies of ammocoetelarvae and adult lampreys (Lampetra nchardsoni) showed the presenceof AVT, but there was no evidence for any "recapitulation" ofan "early" neutral principle. It seemed possible that an apparentrecapitulation might occur only when the principle had a usein fetal life. Therefore the possible actions of AVT (and AVP)in the mammalian fetus (guinea pig) were studied. AVT and AVPwere shown to act on the isolated amnion to slow, and even reversefetal-maternal water movement. AVP acted on the yolk sac, thefetal skin and the fetal bladder to increase water flow inwards,towards the fetus. These actions suggested an extraplacentalmechanism for supplying water to the fetus and its environment,through the extraembryonic membranes. These actions were reminiscentof those known in the anurans. The apparent success of the conceptof recapitulation, in both the molecular and functional fields,may have been fortuitous. However, the results suggest thatphylogenetic considerations may well be useful in understandingthe physiology of the mammal during fetal life.     

Evolutionary Aspects of Cardioprotection

The review addresses the mechanisms of adaptation of the myocardium and cells of the cardiovascular system to hypoxia and ischemia as well as biochemical mechanisms of cardioprotection in animals of different phylogenetic levels. A special focus is placed on general adaptive strategies developed by evolutionarily distant animals in response to hypoxia and ischemia and on preconditioning and myocardial hibernation phenomena.     

Structural, Functional and Phylogenetic Aspects of the Colleter

This article surveys the structural, functional and phylogeneticsignificance of colleters in different dicotyledonous families.Colleters are multicellular secretory structures attached tothe stipule, petiole, lamina, bract, bracteole, calyx and corolla.Colleters are grouped into standard (S), dendroid (D) and brush-like(B) types on the basis of their morphology and structure. Dand B-type colleters occur in certain members of Rubiaceae thatalso have bacterial leaf nodules. Besides the normal structure,epithelial hairs, thin-walled subepidermal cells, laticifersand vasculature are present in many colleters of Apocynaceae.It is probable that the colleter functions to protect the developingmeristem by secreting a viscous fluid. Exudate of D-type colletersare mucilaginous, providing the substrate necessary for thenutrition of endophytic bacteria. Colleter, structure, phylogeny