143 research outputs found

    Stable isotopes infer the diet and habitat of the enigmatic pygmy right whale (Caperea marginata) off southern Australia

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    In the Southern Hemisphere, baleen whales generally undertake migrations between productive feeding grounds at high latitudes and breeding grounds at lower latitudes. Pygmy right whales (Caperea marginata) (PRW) are the smallest and most enigmatic baleen whale, that likely forgo long-distance migrations, and instead inhabit temperate and subantarctic waters year-round. Previous research has relied on limited data from sighting and stranding records to infer the habitat use and diet of PRWs, however the absence of long-term and consistent data has left uncertainty surrounding these parameters. We utilized bulk stable isotopes of carbon (δ13C) and nitrogen (δ15N) in baleen from Australian PRWs (n = 14) to infer their diet and habitat use. Stable isotope values from 1980–2019 were then matched to remote sensed data from known upwelling regions (where they likely feed) to examine if their dietary patterns are related to changes in food web dynamics. We found that PRWs remained in mid-latitude waters year-round and showed no evidence of feeding in Antarctic waters. Rather, their isotopic record suggests they remain between coastal waters off southern Australia and the Subtropical Convergence, feeding on krill and copepods. Additionally, there was a weak positive relationship between PRW nitrogen stable isotope values and sea surface temperature (SST) from the eastern Great Australian Bight (GAB) and Bonney Upwelling. This suggests seasonal changes in their diet is possibly correlated to oceanographic changes which drive food-web dynamics in these regions. Unlike larger species of baleen whales that migrate further to highly productive waters in the Southern Ocean to meet their energetic demands, the small PRW, who only reach 6.5m, may sustain both feeding and breeding requirements at mid-latitudes. This is the first study to analyze long-term dietary and movement patterns of the PRW, providing an important contribution to our understanding of the species

    On the estimation of body mass in temnospondyls: a case study using the large-bodied Eryops and Paracyclotosaurus

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    Temnospondyli are a morphologically varied and ecologically diverse clade of tetrapods that survived for over 200 million years. The body mass of temnospondyls is a key variable in inferring their ecological, physiological and biomechanical attributes. However, estimating the body mass of these extinct creatures has proven difficult because the group has no extant descendants. Here we apply a wide range of body mass estimation techniques developed for tetrapods to the iconic temnospondyls Paracyclotosaurus davidi and Eryops megacephalus. These same methods are also applied to a collection of extant organisms that serve as ecological and morphological analogues. These include the giant salamanders Andrias japonicus and Andrias davidianus, the tiger salamander Ambystoma tigrinum, the California newt Taricha torosa and the saltwater crocodile, Crocodylus porosus. We find that several methods can provide accurate mass estimations across this range of living taxa, suggesting their suitability for estimating the body masses of temnospondyls. Based on this, we estimate the mass of Paracyclotosaurus to have been between 159 and 365 kg, and that of Eryops between 102 and 222 kg. These findings provide a basis for examining body size evolution in this clade across their entire temporal span

    Kontrol Diri Dan Kecemasan Komunikasi Interpersonal Pada Pramuwisata

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    This study aim to analysis relationship of self-control and anxiety of interpersonal communicationin a tourist guide. Product moment corelation analysis (rxy) yields for 0905, to provethe relationship between self-control and interpersonal communication anxiety in a tourist guide.These results indicate a negative relationship between the variables X (Self Control) and variableY (Interpersonal Communication Anxiety in the guides). Social Learning Theory became atheories used in this study, where most of the individual behavior acquired partly the result oflearning through observation of behavior displayed other individuals whose became the model.Elaboration Likelihood Theory which states that each individual will interpret the message orinformation they receive, in accordance with the information they have and their beliefs aboutsomething related to the message. Self-control on the tour guides in Yogyakarta based on thefive major aspects of self-control, that has a very high level of measurement. Includes the abilityto anticipate events, the ability to interpret events and the ability to take decisions. Meanwhile,two other aspects of self control shows the results of measurements at very low category, whichconsists of aspects of behavior and stimulus control. While anxiety based on the three aspects ofinterpersonal communication, which consists of inhibition of the ability to express themselves,lack of interest in communicating and social interaction is interrupted, it indicates the levelmeasurement at very low category. Thus, interpersonal communication anxiety on tour guidesin Yogyakarta can be said to be very low

    A Lagerstätte from Australia provides insight into the nature of Miocene mesic ecosystems

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    Reduced precipitation in the Miocene triggered the geographic contraction of rainforest ecosystems around the world. In Australia, this change was particularly pronounced; mesic rainforest ecosystems that once dominated the landscape transformed into the shrublands, grasslands, and deserts of today. A lack of well-preserved fossils has made it difficult to understand the nature of Australian ecosystems before the aridification. Here, we report on an exceptionally well-preserved rainforest biota from New South Wales, Australia. This Konservat-Lagerstätte hosts a rich diversity of microfossils, plants, insects, spiders, and vertebrate remains preserved in goethite. We document evidence for several species interactions including predation, parasitism, and pollination. The fossils are indicative of an oxbow lake in a mesic rainforest and suggest that rainforest distributions have shifted since the Miocene. The variety of fossils preserved, together with high fidelity of preservation, allows for unprecedented insights into the mesic ecosystems that dominated Australia during the Miocene

    Clawed forelimbs allow northern seals to eat like their ancient ancestors

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    Funding for this project was provided by a Marie Skłodowska-Curie Global Postdoctoral Fellowship (656010/MYSTICETI) to F.G.M, by Marine Scotland to support the wild observations recorded by R.N.H., by an Australian Research Council Future Fellowship FT130100968 to A.R.E., and by an Australian Research Council Linkage Project LP150100403 to A.R.E. and E.M.G.F.Streamlined flippers are often considered the defining feature of seals and sea lions, whose very name ‘pinniped’ comes from the Latin pinna and pedis, meaning ‘fin-footed’. Yet not all pinniped limbs are alike. Whereas otariids (fur seals and sea lions) possess stiff streamlined forelimb flippers, phocine seals (northern true seals) have retained a webbed yet mobile paw bearing sharp claws. Here, we show that captive and wild phocines routinely use these claws to secure prey during processing, enabling seals to tear large fish by stretching them between their teeth and forelimbs. ‘Hold and tear’ processing relies on the primitive forelimb anatomy displayed by phocines, which is also found in the early fossil pinniped Enaliarctos. Phocine forelimb anatomy and behaviour therefore provide a glimpse into how the earliest seals likely fed, and indicate what behaviours may have assisted pinnipeds along their journey from terrestrial to aquatic feeding.Publisher PDFPeer reviewe

    Rare coding variants in PLCG2, ABI3, and TREM2 implicate microglial-mediated innate immunity in Alzheimer's disease

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    We identified rare coding variants associated with Alzheimer’s disease (AD) in a 3-stage case-control study of 85,133 subjects. In stage 1, 34,174 samples were genotyped using a whole-exome microarray. In stage 2, we tested associated variants (P<1×10-4) in 35,962 independent samples using de novo genotyping and imputed genotypes. In stage 3, an additional 14,997 samples were used to test the most significant stage 2 associations (P<5×10-8) using imputed genotypes. We observed 3 novel genome-wide significant (GWS) AD associated non-synonymous variants; a protective variant in PLCG2 (rs72824905/p.P522R, P=5.38×10-10, OR=0.68, MAFcases=0.0059, MAFcontrols=0.0093), a risk variant in ABI3 (rs616338/p.S209F, P=4.56×10-10, OR=1.43, MAFcases=0.011, MAFcontrols=0.008), and a novel GWS variant in TREM2 (rs143332484/p.R62H, P=1.55×10-14, OR=1.67, MAFcases=0.0143, MAFcontrols=0.0089), a known AD susceptibility gene. These protein-coding changes are in genes highly expressed in microglia and highlight an immune-related protein-protein interaction network enriched for previously identified AD risk genes. These genetic findings provide additional evidence that the microglia-mediated innate immune response contributes directly to AD development

    A novel Alzheimer disease locus located near the gene encoding tau protein

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    This is the author accepted manuscript. The final version is available from the publisher via the DOI in this recordAPOE ε4, the most significant genetic risk factor for Alzheimer disease (AD), may mask effects of other loci. We re-analyzed genome-wide association study (GWAS) data from the International Genomics of Alzheimer's Project (IGAP) Consortium in APOE ε4+ (10 352 cases and 9207 controls) and APOE ε4- (7184 cases and 26 968 controls) subgroups as well as in the total sample testing for interaction between a single-nucleotide polymorphism (SNP) and APOE ε4 status. Suggestive associations (P<1 × 10-4) in stage 1 were evaluated in an independent sample (stage 2) containing 4203 subjects (APOE ε4+: 1250 cases and 536 controls; APOE ε4-: 718 cases and 1699 controls). Among APOE ε4- subjects, novel genome-wide significant (GWS) association was observed with 17 SNPs (all between KANSL1 and LRRC37A on chromosome 17 near MAPT) in a meta-analysis of the stage 1 and stage 2 data sets (best SNP, rs2732703, P=5·8 × 10-9). Conditional analysis revealed that rs2732703 accounted for association signals in the entire 100-kilobase region that includes MAPT. Except for previously identified AD loci showing stronger association in APOE ε4+ subjects (CR1 and CLU) or APOE ε4- subjects (MS4A6A/MS4A4A/MS4A6E), no other SNPs were significantly associated with AD in a specific APOE genotype subgroup. In addition, the finding in the stage 1 sample that AD risk is significantly influenced by the interaction of APOE with rs1595014 in TMEM106B (P=1·6 × 10-7) is noteworthy, because TMEM106B variants have previously been associated with risk of frontotemporal dementia. Expression quantitative trait locus analysis revealed that rs113986870, one of the GWS SNPs near rs2732703, is significantly associated with four KANSL1 probes that target transcription of the first translated exon and an untranslated exon in hippocampus (P≤1.3 × 10-8), frontal cortex (P≤1.3 × 10-9) and temporal cortex (P≤1.2 × 10-11). Rs113986870 is also strongly associated with a MAPT probe that targets transcription of alternatively spliced exon 3 in frontal cortex (P=9.2 × 10-6) and temporal cortex (P=2.6 × 10-6). Our APOE-stratified GWAS is the first to show GWS association for AD with SNPs in the chromosome 17q21.31 region. Replication of this finding in independent samples is needed to verify that SNPs in this region have significantly stronger effects on AD risk in persons lacking APOE ε4 compared with persons carrying this allele, and if this is found to hold, further examination of this region and studies aimed at deciphering the mechanism(s) are warranted

    Data from: Hyper-longirostry and kinematic disparity in extinct toothed whales

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    Toothed cetacean (Odontoceti) lineages in the Miocene and Pliocene evolved rostra that are proportionally more elongate than any other aquatic mammal or reptile, living or extinct. Their similarities in cranial proportions to billfish may suggest a convergent feeding style, where the rostrum is swept through the water to hit and stun prey. Here we calculated second moment of area from rostral cross-sections of these fossil odontocete taxa, as well as from extant ecological analogues, to infer variation in feeding behavior. Our results show that the extremely long rostra of extinct toothed whales vary considerably in functionally relevant measures of shape, and likely exhibited a diversity of feeding behaviors, ranging from those similar to modern odontocetes to those convergent with billfish. Eustatic sea-level and temperature maxima of the Miocene likely led to changes in prey characteristics or abundance that enabled the repeated evolution of this extreme morphotype, which later went extinct during late Pliocene climatic deterioration

    Miocene caddisflies from Australia: iron-rich sediments preserve internal organs, tracheoles, and corneal nanocoating of larvae and pupae

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    Trichoptera (caddisflies) are insects with terrestrial adults and aquatic larvae. Although caddisflies spend most of their lives as larvae and pupate in the water, fossils of these stages are rarely found. However, ~100 pupae and uncased larvae were discovered at McGraths Flat, an Australian Miocene Lagerstätte. Many of the fossils are extremely well preserved. In addition to external features that include a spinneret among the mouthparts and claws on the abdominal prolegs, some larvae show silk glands, parts of the gastrointestinal tract, and tracheoles. The pupae are all at the pharate stage; in some, large compound eyes can be seen, and some exhibit male genitalia. Scanning electron microscopy revealed ommatidial structures, such as rhabdoms, corneas, and most remarkably the corneal nanocoating. Two caddisfly morphotypes are preserved at McGraths Flat. The larger morphotype belongs to the suborder Annulipalpia and can be assigned, most probably, to the family Dipseudopsidae. The smaller morphotype closely resembles extant members of the family Hydroptilidae (suborder Spicipalpia). No adult caddisflies or individual wings, no immature pupae, and no larval or pupal cases have been found in the deposit. This unusual fossil record suggests an unstable palaeoenvironment characterized by abrupt change
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